LIGHT-EMITTING DEVICE INCLUDING ORGANOMETALLIC COMPOUND, ELECTRONIC APPARATUS INCLUDING THE LIGHT-EMITTING DEVICE, AND THE ORGANOMETALLIC COMPOUND

Abstract

A light-emitting device including an organometallic compound represented by Formula 1, an electronic apparatus including the light-emitting device, and the organometallic compound represented by Formula 1 are provided:

##STR00001##

Claims

1. A light-emitting device comprising: a first electrode; a second electrode facing the first electrode; an interlayer between the first electrode and the second electrode and comprising an emission layer; and an organometallic compound represented by Formula 1: ##STR00334## wherein, in Formula 1, M is platinum (Pt), palladium (Pd), copper (Cu), silver (Ag), gold (Au), rhodium (Rh), ruthenium (Ru), osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu), terbium (Tb), or thulium (Tm), X.sub.11, X.sub.12, and X.sub.2 to X.sub.4 are each independently C or N, ring CY.sub.1 to ring CY.sub.4 are each independently a C.sub.5-C.sub.30 carbocyclic group or a C.sub.1-C.sub.30 heterocyclic group, L.sub.1 to L.sub.3 are each independently a single bond, *C(R.sub.1a)(R.sub.1b)*, *C(R.sub.1a)*, *C(R.sub.1a)*, *C(R.sub.1a)C(R.sub.1b)*, *C(O)*, *C(S)*, *CC*, *B(R.sub.1a)*, *N(R.sub.1a)*, *O*, *P(R.sub.1a)*, *Al(R.sub.1a)*, *Si(R.sub.1a)(R.sub.1b)*, *P(O)(R.sub.1a)*, *S*, *S(O)*, *S(O).sub.2*, or *Ge(R.sub.1a)(R.sub.1b)*, * and * each indicating a binding site to a neighboring atom, n1 to n3 are each independently an integer from 1 to 5, R.sub.1 to R.sub.4, R.sub.1a, and R.sub.1b are each independently hydrogen, deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.60 alkyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkenyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkynyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 alkoxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 alkylthio group unsubstituted or substituted with at least one R.sub.10a, a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.6-C.sub.60 aryloxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.6-C.sub.60 arylthio group unsubstituted or substituted with at least one R.sub.10a, C(Q.sub.1)(Q.sub.2)(Q.sub.3), Si(Q.sub.1)(Q.sub.2)(Q.sub.3), N(Q.sub.1)(Q.sub.2), B(Q.sub.1)(Q.sub.2), C(O)(Q.sub.1), S(O).sub.2(Q.sub.1), or P(O)(Q.sub.1)(Q.sub.2), a1 to a4 are each independently an integer from 1 to 20, Ar.sub.1 is a group represented by Formula 2-1 or 2-2, when a1 is 2 or more, two or more of R.sub.1(s) in the number of a1 are optionally bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, when a2 is 2 or more, two or more of R.sub.2(s) in the number of a2 are optionally bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, when a3 is 2 or more, two or more of R.sub.3(s) in the number of a3 are optionally bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, when a4 is 2 or more, two or more of R.sub.4(s) in the number of a4 are optionally bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, R.sub.1a and R.sub.1b are optionally bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two or more selected from among R.sub.1 to R.sub.4, R.sub.1a, R.sub.1b, and Ari are optionally bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, in Formulae 2-1 and 2-2, Y.sub.1 and Y.sub.2 are each independently B or N, Y.sub.1 and Y.sub.2 being different from each other, Z.sub.1 to Z.sub.7 are each independently hydrogen, deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.60 alkyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkenyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkynyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 alkoxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 alkylthio group unsubstituted or substituted with at least one R.sub.10a, a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.6-C.sub.60 aryloxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.6-C.sub.60 arylthio group unsubstituted or substituted with at least one R.sub.10a, C(Q.sub.1)(Q.sub.2)(Q.sub.3), Si(Q.sub.1)(Q.sub.2)(Q.sub.3), N(Q.sub.1)(Q.sub.2), B(Q.sub.1)(Q.sub.2), C(O)(Q.sub.1), S(O).sub.2(Q.sub.1), or P(O)(Q.sub.1)(Q.sub.2), * indicates a binding site to X.sub.12 in Formula 1, two or more selected from among Z.sub.1 to Z.sub.7 are optionally bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, R.sub.10a is: deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, or a nitro group; a C.sub.1-C.sub.60 alkyl group, a C.sub.2-C.sub.60 alkenyl group, a C.sub.2-C.sub.60 alkynyl group, or a C.sub.1-C.sub.60 alkoxy group, each unsubstituted or substituted with deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, a nitro group, a C.sub.3-C.sub.60 carbocyclic group, a C.sub.1-C.sub.60 heterocyclic group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.7-C.sub.60 arylalkyl group, a C.sub.2-C.sub.60 heteroarylalkyl group, Si(Q.sub.11)(Q.sub.12)(Q.sub.13), N(Q.sub.11)(Q.sub.12), B(Q.sub.11)(Q.sub.12), C(O)(Q.sub.11), S(O).sub.2(Q.sub.11), P(O)(Q.sub.11)(Q.sub.12), or any combination thereof; a C.sub.3-C.sub.60 carbocyclic group, a C.sub.1-C.sub.60 heterocyclic group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.7-C.sub.60 arylalkyl group, or a C.sub.2-C.sub.60 heteroarylalkyl group, each unsubstituted or substituted with deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.60 alkyl group, a C.sub.2-C.sub.60 alkenyl group, a C.sub.2-C.sub.60 alkynyl group, a C.sub.1-C.sub.60 alkoxy group, a C.sub.3-C.sub.60 carbocyclic group, a C.sub.1-C.sub.60 heterocyclic group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.7-C.sub.60 arylalkyl group, a C.sub.2-C.sub.60 heteroarylalkyl group, Si(Q.sub.21)(Q.sub.22)(Q.sub.23), N(Q.sub.21)(Q.sub.22), B(Q.sub.21)(Q.sub.22), C(O)(Q.sub.21), S(O).sub.2(Q.sub.21), P(O)(Q.sub.21)(Q.sub.22), or any combination thereof; or Si(Q.sub.31)(Q.sub.32)(Q.sub.33), N(Q.sub.31)(Q.sub.32), B(Q.sub.31)(Q.sub.32), C(O)(Q.sub.31), S(O).sub.2(Q.sub.31), or P(O)(Q.sub.31)(Q.sub.32), and Q.sub.1 to Q.sub.3, Q.sub.11 to Q.sub.13, Q.sub.21 to Q.sub.23, and Q.sub.31 to Q.sub.33 are each independently hydrogen; deuterium; F; Cl; Br; I; a hydroxyl group; a cyano group; a nitro group; a C.sub.1-C.sub.60 alkyl group; a C.sub.2-C.sub.60 alkenyl group; a C.sub.2-C.sub.60 alkynyl group; a C.sub.1-C.sub.60 alkoxy group; or a C.sub.5-C.sub.60 carbocyclic group, a C.sub.1-C.sub.60 heterocyclic group, a C.sub.7-C.sub.60 arylalkyl group, or a C.sub.2-C.sub.60 heteroarylalkyl group, each unsubstituted or substituted with deuterium, F, a cyano group, a C.sub.1-C.sub.60 alkyl group, a C.sub.1-C.sub.60 alkoxy group, a phenyl group, a biphenyl group, or any combination thereof.

2. The light-emitting device of claim 1, wherein the emission layer comprises a host and a dopant, and the dopant comprises the organometallic compound.

3. The light-emitting device of claim 1, further comprising: a second compound comprising at least one electron-deficient nitrogen-containing C.sub.1-C.sub.60 heterocyclic group; a third compound comprising a group represented by Formula 3; a fourth compound capable of emitting delayed fluorescence; or any combination thereof, wherein the organometallic compound, the second compound, the third compound, and the fourth compound are different from each other, ##STR00335## and wherein, in Formula 3, ring CY.sub.71 and ring CY.sub.72 are each independently a Ir electron-rich C.sub.3-C.sub.60 cyclic group or a pyridine group, X.sub.71 is a single bond, or a linking group comprising O, S, N, B, C, Si, or any combination thereof, and * indicates a binding site to any atom included in the remaining part other than the group represented by Formula 3 in the third compound.

4. The light-emitting device of claim 3, wherein the second compound comprises a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, or any combination thereof, and the fourth compound is a compound comprising at least one cyclic group comprising each of boron (B) and nitrogen (N) as a ring-forming atom.

5. The light-emitting device of claim 3, wherein the emission layer comprises: i) the organometallic compound; and ii) the second compound, the third compound, the fourth compound, or any combination thereof, and wherein the emission layer is to emit blue light.

6. An electronic apparatus comprising the light-emitting device of claim 1.

7. The electronic apparatus of claim 6, further comprising a thin-film transistor, wherein the thin-film transistor comprises a source electrode and a drain electrode, and the first electrode of the light-emitting device is electrically connected to the source electrode or the drain electrode of the thin-film transistor.

8. The electronic apparatus of claim 6, further comprising a color filter, a color conversion layer, a touch-screen layer, a polarizing layer, or any combination thereof.

9. An electronic equipment comprising the light-emitting device of claim 1.

10. The electronic equipment of claim 9, wherein the electronic equipment is at least one of a flat panel display, a curved display, a computer monitor, a medical monitor, a television, a billboard, an indoor or outdoor light and/or light for signal, a head-up display, a fully or partially transparent display, a flexible display, a rollable display, a foldable display, a stretchable display, a laser printer, a telephone, a portable phone, a tablet personal computer, a phablet, a personal digital assistant (PDA), a wearable device, a laptop computer, a digital camera, a camcorder, a viewfinder, a micro display, a three-dimensional (3D) display, a virtual reality or augmented reality display, a vehicle, a video wall with multiple displays tiled together, a theater or stadium screen, a phototherapy device, or a signboard.

11. An organometallic compound represented by Formula 1: ##STR00336## wherein, in Formula 1, M is platinum (Pt), palladium (Pd), copper (Cu), silver (Ag), gold (Au), rhodium (Rh), ruthenium (Ru), osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu), terbium (Tb), or thulium (Tm), X.sub.11, X.sub.12, and X.sub.2 to X.sub.4 are each independently C or N, ring CY.sub.1 to ring CY.sub.4 are each independently a C.sub.5-C.sub.30 carbocyclic group or a C.sub.1-C.sub.30 heterocyclic group, L.sub.1 to L.sub.3 are each independently a single bond, *C(R.sub.1a)(R.sub.1b)*, *C(R.sub.1a)*, *C(R.sub.1a)*, *C(R.sub.1a)C(R.sub.1b)*, *C(O)*, *C(S)*, *CC*, *B(R.sub.1a)*, *N(R.sub.1a)*, *O*, *P(Ra)*, *Al(R.sub.1a)*, *Si(R.sub.1a)(R.sub.1b)*, *P(O)(R.sub.1a)*, *S*, *S(O)*, *S(O).sub.2*, or *Ge(R.sub.1a)(R.sub.1b)*, * and * each indicating a binding site to a neighboring atom, n1 to n3 are each independently an integer from 1 to 5, R.sub.1 to R.sub.4, R.sub.1a, and R.sub.1b are each independently hydrogen, deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.60 alkyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkenyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkynyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 alkoxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 alkylthio group unsubstituted or substituted with at least one R.sub.10a, a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.6-C.sub.60 aryloxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.6-C.sub.60 arylthio group unsubstituted or substituted with at least one R.sub.10a, C(Q.sub.1)(Q.sub.2)(Q.sub.3), Si(Q.sub.1)(Q.sub.2)(Q.sub.3), N(Q.sub.1)(Q.sub.2), B(Q.sub.1)(Q.sub.2), C(O)(Q.sub.1), S(O).sub.2(Q.sub.1), or P(O)(Q.sub.1)(Q.sub.2), a1 to a4 are each independently an integer from 1 to 20, Ar.sub.1 is a group represented by Formula 2-1 or 2-2, when a1 is 2 or more, two or more of R.sub.1(s) in the number of a1 are optionally bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, when a2 is 2 or more, two or more of R.sub.2(s) in the number of a2 are optionally bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, when a3 is 2 or more, two or more of R.sub.3(s) in the number of a3 are optionally bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group that is unsubstituted or substituted with at least one R.sub.10a, when a4 is 2 or more, two or more of R.sub.4(s) in the number of a4 are optionally bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group that is unsubstituted or substituted with at least one R.sub.10a, R.sub.1a and R.sub.1b are optionally bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two or more selected from among R.sub.1 to R.sub.4, R.sub.1a, R.sub.1b, and Ari are optionally bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, in Formulae 2-1 and 2-2, Y.sub.1 and Y.sub.2 are each independently B or N, Y.sub.1 and Y.sub.2 being different from each other, Z.sub.1 to Z.sub.7 are each independently hydrogen, deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.60 alkyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkenyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkynyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 alkoxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 alkylthio group unsubstituted or substituted with at least one R.sub.10a, a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.6-C.sub.60 aryloxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.6-C.sub.60 arylthio group unsubstituted or substituted with at least one R.sub.10a, C(Q.sub.1)(Q.sub.2)(Q.sub.3), Si(Q.sub.1)(Q.sub.2)(Q.sub.3), N(Q.sub.1)(Q.sub.2), B(Q.sub.1)(Q.sub.2), C(O)(Q.sub.1), S(O).sub.2(Q.sub.1), or P(O)(Q.sub.1)(Q.sub.2), * indicates a binding site to X.sub.12 in Formula 1, two or more selected from among Z.sub.1 to Z.sub.7 are optionally bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, R.sub.10a is: deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, or a nitro group; a C.sub.1-C.sub.60 alkyl group, a C.sub.2-C.sub.60 alkenyl group, a C.sub.2-C.sub.60 alkynyl group, or a C.sub.1-C.sub.60 alkoxy group, each unsubstituted or substituted with deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, a nitro group, a C.sub.5-C.sub.60 carbocyclic group, a C.sub.1-C.sub.60 heterocyclic group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.7-C.sub.60 arylalkyl group, a C.sub.2-C.sub.60 heteroarylalkyl group, Si(Q.sub.11)(Q.sub.12)(Q.sub.13), N(Q.sub.11)(Q.sub.12), B(Q.sub.11)(Q.sub.12), C(O)(Q.sub.11), S(O).sub.2(Q.sub.11), P(O)(Q.sub.11)(Q.sub.12), or any combination thereof; a C.sub.3-C.sub.60 carbocyclic group, a C.sub.1-C.sub.60 heterocyclic group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.7-C.sub.60 arylalkyl group, or a C.sub.2-C.sub.60 heteroarylalkyl group, each unsubstituted or substituted with deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.60 alkyl group, a C.sub.2-C.sub.60 alkenyl group, a C.sub.2-C.sub.60 alkynyl group, a C.sub.1-C.sub.60 alkoxy group, a C.sub.3-C.sub.60 carbocyclic group, a C.sub.1-C.sub.60 heterocyclic group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.7-C.sub.60 arylalkyl group, a C.sub.2-C.sub.60 heteroarylalkyl group, Si(Q.sub.21)(Q.sub.22)(Q.sub.23), N(Q.sub.21)(Q.sub.22), B(Q.sub.21)(Q.sub.22), C(O)(Q.sub.21), S(O).sub.2(Q.sub.21), P(O)(Q.sub.21)(Q.sub.22), or any combination thereof; or Si(Q.sub.31)(Q.sub.32)(Q.sub.33), N(Q.sub.31)(Q.sub.32), B(Q.sub.31)(Q.sub.32), C(O)(Q.sub.31), S(O).sub.2(Q.sub.31), or P(O)(Q.sub.31)(Q.sub.32), and Q.sub.1 to Q.sub.3, Q.sub.11 to Q.sub.13, Q.sub.21 to Q.sub.23, and Q.sub.31 to Q.sub.33 are each independently hydrogen; deuterium; F; Cl; Br; I; a hydroxyl group; a cyano group; a nitro group; a C.sub.1-C.sub.60 alkyl group; a C.sub.2-C.sub.60 alkenyl group; a C.sub.2-C.sub.60 alkynyl group; a C.sub.1-C.sub.60 alkoxy group; or a C.sub.3-C.sub.60 carbocyclic group, a C.sub.1-C.sub.60 heterocyclic group, a C.sub.7-C.sub.60 arylalkyl group, or a C.sub.2-C.sub.60 heteroarylalkyl group, each unsubstituted or substituted with deuterium, F, a cyano group, a C.sub.1-C.sub.60 alkyl group, a C.sub.1-C.sub.60 alkoxy group, a phenyl group, a biphenyl group, or any combination thereof.

12. The organometallic compound of claim 11, wherein M is Pt, Pd, or Au.

13. The organometallic compound of claim 11, wherein X.sub.11, X.sub.2, and X.sub.3 are each C, and X.sub.4 is N, a bond between X.sub.11 and M and a bond between X.sub.4 and M are each a coordinate bond, and a bond between X.sub.2 and M and a bond between X.sub.3 and M are each a covalent bond.

14. The organometallic compound of claim 11, wherein X.sub.12 is N.

15. The organometallic compound of claim 11, wherein ring CY.sub.1 to ring CY.sub.4 are each independently: a benzene group, a naphthalene group, an anthracene group, a phenanthrene group, a triphenylene group, a pyrene group, a chrysene group, a cyclopentadiene group, a furan group, a thiophene group, a silole group, an indene group, a fluorene group, an indole group, a carbazole group, a benzofuran group, a dibenzofuran group, a benzothiophene group, a dibenzothiophene group, a benzosilole group, a dibenzosilole group, an azafluorene group, an azacarbazole group, an azadibenzofuran group, an azadibenzothiophene group, an azadibenzosilole group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, a quinoline group, an isoquinoline group, a quinoxaline group, a quinazoline group, a phenanthroline group, a pyrrole group, a pyrazole group, an imidazole group, a triazole group, an oxazole group, an isoxazole group, a thiazole group, an isothiazole group, a oxadiazole group, a thiadiazole group, a benzopyrazole group, a benzimidazole group, a benzoxazole group, a benzothiazole group, a benzoxadiazole group, a benzothiadiazole group, a dibenzoxasiline group, a dibenzothiasiline group, a dibenzodihydroazasiline group, a dibenzodihydrodisiline group, a dibenzodihydrosiline group, a dibenzodioxin group, dibenzoxathine group, a dibenzoxazine group, a dibenzopyran group, a dibenzodithine group, a dibenzothiazine group, a dibenzothiopyran group, a dibenzocyclohexadiene group, a dibenzodihydropyridine group, or a dibenzodihydropyrazine group.

16. The organometallic compound of claim 11, wherein L.sub.1 and L.sub.3 are each a single bond, and L.sub.2 is *O* or *S*, and n2 is 1.

17. The organometallic compound of claim 11, wherein R.sub.1 to R.sub.4 and Z.sub.1 to Z.sub.7 are each independently: hydrogen, deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.20 alkyl group, or a C.sub.1-C.sub.20 alkoxy group; a C.sub.1-C.sub.20 alkyl group or a C.sub.1-C.sub.20 alkoxy group, each substituted with deuterium, F, Cl, Br, I, CD.sub.3, CD.sub.2H, CDH.sub.2, CF.sub.3, CF.sub.2H, CFH.sub.2, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.10 alkyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a naphthyl group, a pyridinyl group, a pyrimidinyl group, or any combination thereof; a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a (C.sub.1-C.sub.10 alkyl)phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group, a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a benzothiazolyl group, a benzoisoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, an azacarbazolyl group, an azadibenzofuranyl group, an azadibenzothiophenyl group, an azafluorenyl group, or an azadibenzosilolyl group, each unsubstituted or substituted with deuterium, F, Cl, Br, I, CD.sub.3, CD.sub.2H, CDH.sub.2, CF.sub.3, CF.sub.2H, CFH.sub.2, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a (C.sub.1-C.sub.10 alkyl)phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group, a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a benzoisothiazolyl group, a benzoxazolyl group, a benzoisoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, O(Q.sub.31), S(Q.sub.31), Si(Q.sub.31)(Q.sub.32)(Q.sub.33), N(Q.sub.31)(Q.sub.32), B(Q.sub.31)(Q.sub.32), P(Q.sub.31)(Q.sub.32), C(O)(Q.sub.31), S(O).sub.2(Q.sub.31), P(O)(Q.sub.31)(Q.sub.32), or any combination thereof; or C(Q.sub.1)(Q.sub.2)(Q.sub.3), Si(Q.sub.1)(Q.sub.2)(Q.sub.3), N(Q.sub.1)(Q.sub.2), B(Q.sub.1)(Q.sub.2), C(O)(Q.sub.1), S(O).sub.2(Q.sub.1), or P(O)(Q.sub.1)(Q.sub.2), and Q.sub.1 to Q.sub.3 and Q.sub.31 to Q.sub.33 are each independently: hydrogen; deuterium; F; Cl; Br; I; a hydroxyl group; a cyano group; a nitro group; a C.sub.1-C.sub.60 alkyl group; a C.sub.2-C.sub.60 alkenyl group; a C.sub.2-C.sub.60 alkynyl group; a C.sub.1-C.sub.60 alkoxy group; or a C.sub.3-C.sub.60 carbocyclic group or a C.sub.1-C.sub.60 heterocyclic group, each unsubstituted or substituted with deuterium, F, a cyano group, a C.sub.1-C.sub.60 alkyl group, a C.sub.1-C.sub.60 alkoxy group, a phenyl group, a biphenyl group, or any combination thereof.

18. The organometallic compound of claim 11, wherein at least two selected from among Z.sub.1 to Z.sub.7 are each not hydrogen.

19. The organometallic compound of claim 11, wherein, in Formula 1, a group represented by ##STR00337## is a group represented by one of Formulae CY1(1) to CY1(11), a group represented by ##STR00338## is a group represented by one of Formulae CY2(1) to CY2(13), a group represented by ##STR00339## is a group represented by one of Formulae CY3(1) to CY3(25), and a group represented by ##STR00340## is a group represented by one of Formulae CY4(1) to CY4(29): ##STR00341## ##STR00342## ##STR00343## ##STR00344## ##STR00345## ##STR00346## ##STR00347## ##STR00348## ##STR00349## ##STR00350## ##STR00351## and wherein, in Formulae CY1(1) to CY1(11), CY2(1) to CY2(13), CY3(1) to CY3(25), and CY4(1) to CY4(29), Ar.sub.1 is the same as defined in Formula 1, T.sub.21 is B(Y.sub.21), C(Y.sub.21)(Y.sub.22), N(Y.sub.21), O, S, or Si(Y.sub.21)(Y.sub.22), T.sub.22 is C(Y.sub.21), N, or Si(Y.sub.21), T.sub.31 is B(Y.sub.31), C(Y.sub.31)(Y.sub.32), N(Y.sub.31), O, S, or Si(Y.sub.31)(Y.sub.32), T.sub.32 is C(Y.sub.31), N, or Si(Y.sub.31), R.sub.11 to R.sub.18 are each the same as defined with respect to R.sub.1 in Formula 1, R.sub.21 to R.sub.26, Y.sub.21, and Y.sub.22 are each the same as defined with respect to R.sub.2 in Formula 1, R.sub.31 to R.sub.36, Y.sub.31, and Y.sub.32 are each the same as defined with respect to R.sub.3 in Formula 1, R.sub.41 to R.sub.47 are each the same defined as with respect to R.sub.4 in Formula 1, * indicates a binding site to M in Formula 1, * indicates a binding site to L.sub.1 in Formula 1, * indicates a binding site to L.sub.2 in Formula 1, and * indicates a binding site to L.sub.3 in Formula 1.

20. The organometallic compound of claim 11, wherein the organometallic compound is represented by Formula 1-1 or 1-2: ##STR00352## and wherein, in Formulae 1-1 and 1-2, M, Y.sub.1, Y.sub.2, and Z.sub.1 to Z.sub.7 are each the same as defined in Formula 1, L.sub.2 is *O* or *S*, X.sub.13 is C(R.sub.13) or N, X.sub.14 is C(R.sub.14) or N, X.sub.15 is C(R.sub.15) or N, and X.sub.16 is C(R.sub.16) or N, X.sub.21 is C(R.sub.21) or N, X.sub.22 is C(R.sub.22) or N, and X.sub.23 is C(R.sub.23) or N, X.sub.31 is C(R.sub.31) or N, X.sub.32 is C(R.sub.32) or N, X.sub.33 is C(R.sub.33) or N, X.sub.34 is C(R.sub.34) or N, X.sub.35 is C(R.sub.35) or N, and X.sub.36 is C(R.sub.36) or N, X.sub.41 is C(R.sub.41) or N, X.sub.42 is C(R.sub.42) or N, X.sub.43 is C(R.sub.43) or N, and X.sub.44 is C(R.sub.44) or N, R.sub.13 to R.sub.16 are each the same as defined with respect to R.sub.1 in Formula 1, R.sub.21 to R.sub.23 are each the same as defined with respect to R.sub.2 in Formula 1, R.sub.31 to R.sub.36 are each the same as defined with respect to R.sub.3 in Formula 1, R.sub.41 to R.sub.44 are each the same as defined with respect to R.sub.4 in Formula 1, two or more selected from among R.sub.13 to R.sub.16 are optionally bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two or more selected from among R.sub.21 to R.sub.23 are optionally bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two or more selected from among R.sub.31 to R.sub.36 are optionally bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two or more selected from among R.sub.41 to R.sub.44 are optionally bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two or more selected from among R.sub.13 to R.sub.16, R.sub.21 to R.sub.23, R.sub.31 to R.sub.36, R.sub.41 to R.sub.44, and Z.sub.1 to Z.sub.7 are optionally bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two or more selected from among Z.sub.1 to Z.sub.7 are optionally bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, and R.sub.10a is the same as defined in Formula 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The accompanying drawings are included to provide a further understanding of the present disclosure and are incorporated in and constitute a part of the present disclosure. The drawings illustrate embodiments of the present disclosure and, together with the description, serve to explain principles of the present disclosure. The above and other aspects, features, and advantages of certain embodiments of the disclosure will be more apparent from the following description taken in conjunction with the accompanying drawings, in which:

[0042] FIG. 1 is a schematic view of a structure of a light-emitting device according to one or more embodiments of the present disclosure;

[0043] FIG. 2 is a schematic view of a structure of an electronic apparatus according to one or more embodiments of the present disclosure;

[0044] FIG. 3 is a schematic view of a structure of an electronic apparatus according to one or more embodiments of the present disclosure; and

[0045] FIGS. 4, 5, 6A, 6B, and 6C are each a schematic view of a structure of electronic equipment according to one or more embodiments of the present disclosure.

DETAILED DESCRIPTION

[0046] Reference will now be made in more detail to embodiments, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout the present disclosure, and duplicative descriptions thereof may not be provided for conciseness. In this regard, the embodiments of the present disclosure may have different forms and should not be construed as being limited to the descriptions set forth herein. Accordingly, the embodiments of the present disclosure are merely described, by referring to the drawings, to explain aspects of the present disclosure. As utilized herein, the term and/or or or may include any and all combinations of one or more of the associated listed items. Throughout the disclosure, the expressions such as at least one of, one of, and selected from, when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list. For example, at least one of a, b or c, at least one selected from a, b, and c, at least one selected from among a to c, etc., may indicate only a, only b, only c, both (e.g., simultaneously) a and b, both (e.g., simultaneously) a and c, both (e.g., simultaneously) b and c, all of a, b, and c, or variations thereof. The / utilized herein may be interpreted as and or as or depending on the situation.

[0047] According to one or more embodiments of the present disclosure, a light-emitting device may include: [0048] a first electrode; [0049] a second electrode facing the first electrode; [0050] an interlayer between the first electrode and the second electrode and including an emission layer; and [0051] an organometallic compound represented by Formula 1:

##STR00003## [0052] wherein the description of Formula 1 provided elsewhere herein is incorporated hereby by reference (e.g., is provided in more detail elsewhere herein).

[0053] In one or more embodiments, [0054] the first electrode of the light-emitting device may be an anode, [0055] the second electrode of the light-emitting device may be a cathode, and [0056] the interlayer may further include a hole transport region between the first electrode and the emission layer and an electron transport region between the emission layer and the second electrode, [0057] the hole transport region may include a hole injection layer, a hole transport layer, an emission auxiliary layer, an electron blocking layer, or any combination thereof, and [0058] the electron transport region may include a hole blocking layer, an electron transport layer, an electron injection layer, or any combination thereof.

[0059] In one or more embodiments, the interlayer of the light-emitting device may include the organometallic compound represented by Formula 1.

[0060] In one or more embodiments, the emission layer of the light-emitting device may include the organometallic compound represented by Formula 1 (e.g., as a first compound).

[0061] In one or more embodiments, the emission layer of the light-emitting device may include a dopant and a host, and the dopant may include the organometallic compound represented by Formula 1. For example, in some embodiments, the organometallic compound may act as a dopant. For example, in some embodiments, the emission layer may be to emit blue light. The blue light may have a maximum emission wavelength in a range of, for example, about 430 nm to about 480 nm.

[0062] In one or more embodiments, the electron transport region of the light-emitting device may include a hole blocking layer, and the hole blocking layer may include a phosphine oxide-containing compound, a silicon-containing compound, or any combination thereof. In one or more embodiments, the hole blocking layer may directly contact the emission layer.

[0063] In one or more embodiments, the light-emitting device may further include: a second compound including at least one electron-deficient nitrogen-containing C.sub.1-C.sub.60 heterocyclic group; a third compound including a group represented by Formula 3; a fourth compound capable of emitting delayed fluorescence; or any combination thereof, [0064] wherein the organometallic compound (e.g., as the first compound), the second compound, the third compound, and the fourth compound in the light-emitting device may be different from each other:

##STR00004## [0065] wherein, in Formula 3, [0066] ring CY.sub.71 and ring CY.sub.72 may each independently be a electron-rich C.sub.3-C.sub.60 cyclic group or a pyridine group, [0067] X.sub.71 may be a single bond, or a linking group including O, S, N, B, C, Si, or any combination thereof, and [0068] * indicates a binding site to any atom included in the remaining part other than the group represented by Formula 3 in the third compound.

[0069] In one or more embodiments, the organometallic compound may include at least one deuterium.

[0070] In one or more embodiments, the second compound, the third compound, and the fourth compound may each include at least one deuterium.

[0071] In one or more embodiments, the second compound may include at least one silicon.

[0072] In one or more embodiments, the third compound may include at least one silicon.

[0073] In one or more embodiments, the light-emitting device may further include, in addition to the organometallic compound represented by Formula 1, the second compound and the third compound, wherein at least one selected from among the second compound and the third compound may include at least one deuterium, at least one silicon, or a combination thereof.

[0074] In one or more embodiments, the light-emitting device (e.g., the emission layer in the light-emitting device) may further include, in addition to the organometallic compound, the second compound. At least one selected from among the organometallic compound and the second compound may include at least one deuterium. In one or more embodiments, the light-emitting device (e.g., the emission layer in the light-emitting device) may further include, in addition to the organometallic compound and the second compound, the third compound, the fourth compound, or any combination thereof.

[0075] In one or more embodiments, the light-emitting device (e.g., the emission layer in the light-emitting device) may further include, in addition to the organometallic compound, the third compound. At least one selected from among the organometallic compound and the third compound may include at least one deuterium. In one or more embodiments, the light-emitting device (e.g., the emission layer in the light-emitting device) may further include, in addition to the organometallic compound and the third compound, the second compound, the fourth compound, or any combination thereof.

[0076] In one or more embodiments, the light-emitting device (e.g., the emission layer in the light-emitting device) may further include, in addition to the organometallic compound, the fourth compound. At least one of the organometallic compound and the fourth compound may include at least one deuterium. The fourth compound may have roles in improving color purity, luminescence efficiency, and lifespan characteristics of the light-emitting device. In one or more embodiments, the light-emitting device (e.g., the emission layer in the light-emitting device) may further include, in addition to the organometallic compound and the fourth compound, the second compound, the third compound, or any combination thereof.

[0077] In one or more embodiments, the light-emitting device (e.g., the emission layer in the light-emitting device) may further include, in addition to the organometallic compound, the second compound and the third compound. The second compound and the third compound may form an exciplex. At least one selected from among the organometallic compound, the second compound, and the third compound may include at least one deuterium.

[0078] In one or more embodiments, the emission layer in the light-emitting device may include: i) the organometallic compound; and ii) the second compound, the third compound, the fourth compound, or any combination thereof, and the emission layer may be to emit blue light.

[0079] In one or more embodiments, the blue light may have a maximum emission wavelength in a range of about 430 nm to about 480 nm, about 430 nm to about 475 nm, about 440 nm to about 475 nm, about 450 nm to about 475 nm, about 430 nm to about 470 nm, about 440 nm to about 470 nm, about 450 nm to about 470 nm, about 430 nm to about 465 nm, about 440 nm to about 465 nm, about 450 nm to about 465 nm, about 430 nm to about 460 nm, about 440 nm to about 460 nm, or about 450 nm to about 460 nm.

[0080] In one or more embodiments, the second compound may include a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, or any combination thereof.

[0081] In one or more embodiments, the following compounds may be excluded from the third compound:

##STR00005##

[0082] In one or more embodiments, a difference between a triplet energy level (eV) of the fourth compound and a singlet energy level (eV) of the fourth compound may be about 0 eV or higher and about 0.5 eV or lower (or about 0 eV or higher and about 0.3 eV or lower).

[0083] In one or more embodiments, the fourth compound may be a compound including at least one cyclic group including each of boron (B) and nitrogen (N) as a ring-forming atom.

[0084] In one or more embodiments, the fourth compound may be a C.sub.8-C.sub.60 polycyclic group-containing compound including two or more cyclic groups that are condensed while sharing B (e.g., one being a first ring and another being a second ring).

[0085] In one or more embodiments, the fourth compound may include a condensed ring in which at least one third ring is condensed with at least one fourth ring (e.g., to form the condensed ring including four or more rings), [0086] wherein the third ring may be a cyclopentane group, a cyclohexane group, a cycloheptane group, a cyclooctane group, a cyclopentene group, a cyclohexene group, a cycloheptene group, a cyclooctene group, an adamantane group, a norbornene group, a norbornane group, a bicyclo[1.1.1]pentane group, a bicyclo[2.1.1]hexane group, a bicyclo[2.2.2]octane group, a benzene group, a pyridine group, a pyrimidine group, a pyridazine group, a pyrazine group, or a triazine group, and [0087] the fourth ring may be a 1,2-azaborinine group, a 1,3-azaborinine group, a 1,4-azaborinine group, a 1,2-dihydro-1,2-azaborinine group, a 1,4-oxaborinine group, a 1,4-thiaborinine group, or a 1,4-dihydroborinine group.

[0088] In one or more embodiments, the third compound may not include (e.g., may exclude) a (e.g., any) compound represented by Formula 3-1 described in the present disclosure. In present disclosure, not include a or any component exclude a or any component, component-free, and/or the like refers to that the component not being added, selected or utilized as a component in the composition/element, but, in some embodiments, the component of less than a suitable amount may still be included due to other impurities and/or external factors.

[0089] In one or more embodiments, the second compound may include a compound represented by Formula 2:

##STR00006## [0090] wherein, in Formula 2, [0091] L.sub.51 to L.sub.53 may each independently be a single bond, a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a, or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, [0092] b51 to b53 may each independently be an integer from 1 to 5, [0093] X.sub.54 may be N or C(R.sub.54), X.sub.55 may be N or C(R.sub.55), X.sub.56 may be N or C(R.sub.56), and at least one selected from among X.sub.54 to X.sub.56 may be N, and [0094] R.sub.51 to R.sub.56 and R.sub.10a may each be the same as described in the present disclosure.

[0095] In one or more embodiments, the third compound may include a compound represented by Formula 3-1, a compound represented by Formula 3-2, a compound represented by Formula 3-3, a compound represented by Formula 3-4, a compound represented by Formula 3-5, or any combination thereof:

##STR00007## ##STR00008## [0096] wherein, in Formulae 3-1 to 3-5, [0097] ring CY.sub.71 to ring CY.sub.74 may each independently be a electron-rich C.sub.3-C.sub.60 cyclic group or a pyridine group, [0098] X.sub.82 may be a single bond, O, S, N-[(L.sub.82).sub.b82-R.sub.82], C(R.sub.82a)(R.sub.82b), or Si(R.sub.82a)(R.sub.82b), [0099] X.sub.83 may be a single bond, O, S, N-[(L.sub.83).sub.b83-R.sub.83], C(R.sub.83a)(R.sub.83b), or Si(R.sub.83a)(R.sub.83b), [0100] X.sub.84 may be O, S, N-[(L.sub.84).sub.b84-R.sub.84], C(R.sub.84a)(R.sub.84b), or Si(R.sub.84a)(R.sub.84b), [0101] X.sub.85 may be C or Si, [0102] L.sub.81 to L.sub.85 may each independently be a single bond, *C(Q.sub.4)(Q.sub.5)-*, *Si(Q.sub.4)(Q.sub.5)-*, a electron-rich C.sub.3-C.sub.60 cyclic group unsubstituted or substituted with at least one R.sub.10a, or a pyridine group unsubstituted or substituted with at least one R.sub.10a, wherein Q.sub.4 and Q.sub.5 may each be the same as described with respect to Q.sub.1, [0103] b81 to b85 may each independently be an integer from 1 to 5, [0104] R.sub.71 to R.sub.74, R.sub.81 to R.sub.85, R.sub.82a, R.sub.82b, R.sub.83a, R.sub.83b, R.sub.84a, and R.sub.84b may each be the same as described in the present disclosure, [0105] a71 to a74 may each independently be an integer from 0 to 20, and [0106] R.sub.10a may be the same as described herein.

[0107] In one or more embodiments, the fourth compound may be a compound represented by Formula 502, a compound represented by Formula 503, or any combination thereof:

##STR00009## [0108] wherein, in Formulae 502 and 503, [0109] ring A.sub.501 to ring A.sub.504 may each independently be a C.sub.3-C.sub.60 carbocyclic group or a C.sub.1-C.sub.60 heterocyclic group, [0110] Y.sub.505 may be O, S, N(R.sub.505), B(R.sub.505), C(R.sub.505a)(R.sub.505b), or Si(R.sub.505a)(R.sub.505b), [0111] Y.sub.506 may be O, S, N(R.sub.506), B(R.sub.506), C(R.sub.506a)(R.sub.506b), or Si(R.sub.506a)(R.sub.506b), [0112] Y.sub.507 may be O, S, N(R.sub.507), B(R.sub.507), C(R.sub.507a)(R.sub.507b), or Si(R.sub.507a)(R.sub.507b), [0113] Y.sub.508 may be O, S, N(R.sub.508), B(R.sub.508), C(R.sub.508a)(R.sub.508b), or Si(R.sub.508a)(R.sub.508b), [0114] Y.sub.51 and Y.sub.52 may each independently be B, P(O), or S(O), [0115] R.sub.500a, R.sub.500b, R.sub.501 to R.sub.508, R.sub.505a, R.sub.505b, R.sub.506a, R.sub.506b, R.sub.507a, R.sub.507b, R.sub.508a, and R.sub.508b may each be the same as described in the present disclosure, and [0116] a501 to a504 may each independently be an integer from 0 to 20.

[0117] In one or more embodiments, the light-emitting device may satisfy at least one condition selected from among Conditions 1 to 4:

Condition 1

[0118] Lowest unoccupied molecular orbital (LUMO) energy level (eV) of third compound>LUMO energy level (eV) of organometallic compound;

Condition 2

[0119] LUMO energy level (eV) of organometallic compound>LUMO energy level (eV) of second compound;

Condition 3

[0120] highest occupied molecular orbital (HOMO) energy level (eV) of organometallic compound>HOMO energy level (eV) of third compound; and

Condition 4

[0121] HOMO energy level (eV) of the third compound>HOMO energy level (eV) of the second compound.

[0122] Each of the HOMO energy level and LUMO energy level of each of the organometallic compound, the second compound, and the third compound may be a negative value, and may be measured according to a suitable method.

[0123] In one or more embodiments, an absolute value of a difference between the LUMO energy level of the organometallic compound and the LUMO energy level of the second compound may be about 0.1 eV or higher and about 1.0 eV or lower, an absolute value of a difference between the LUMO energy level of the organometallic compound and the LUMO energy level of the third compound may be about 0.1 eV or higher and about 1.0 eV or lower, an absolute value of a difference between the HOMO energy level of the organometallic compound and the HOMO energy level of the second compound may be about 1.25 eV or lower (for example, about 1.25 eV or lower and about 0.2 eV or higher), and an absolute value of a difference between the HOMO energy level of the organometallic compound and the HOMO energy level of the third compound may be about 1.25 eV or lower (for example, about 1.25 eV or lower and about 0.2 eV or higher).

[0124] When the relationships between the LUMO energy level and HOMO energy level satisfy the conditions as described above, a balance between holes and electrons injected into the emission layer may be achieved.

[0125] The light-emitting device may have a structure of a first embodiment or a second embodiment.

First Embodiment

[0126] According to the first embodiment, the organometallic compound may be included in the emission layer of the interlayer in the light-emitting device, wherein the emission layer may further include a host, the organometallic compound may be different from the host, and the emission layer may be to emit phosphorescence or fluorescence emitted from the organometallic compound. For example, according to the first embodiment, the organometallic compound may be a dopant or an emitter. In one or more embodiments, the organometallic compound may be a phosphorescent dopant or a phosphorescent emitter.

[0127] Phosphorescence or fluorescence emitted from the organometallic compound may be blue light.

[0128] In one or more embodiments, the emission layer may further include an auxiliary dopant. The auxiliary dopant may effectively transfer energy to the organometallic compound which serves as a dopant or an emitter, and in this regard, the auxiliary dopant may serve to improve luminescence efficiency of the organometallic compound.

[0129] The auxiliary dopant may be different from each of the organometallic compound and the host.

[0130] In one or more embodiments, the auxiliary dopant may be a compound capable of emitting delayed fluorescence.

[0131] In one or more embodiments, the auxiliary dopant may be a compound including at least one cyclic group including each of B and N as ring-forming atoms.

Second Embodiment

[0132] According to the second embodiment, the organometallic compound may be included in the emission layer of the interlayer in the light-emitting device, wherein the emission layer may further include a host and a dopant, the organometallic compound, the host, and the dopant may be different from one another, and the emission layer may be to emit phosphorescence or fluorescence (e.g., delayed fluorescence) from the dopant.

[0133] In one or more embodiments, the organometallic compound in the second embodiment may serve as an auxiliary dopant that transfers energy to a dopant (or an emitter), not as a dopant.

[0134] In one or more embodiments, the organometallic compound in the second embodiment may serve as an emitter and also as an auxiliary dopant that transfers energy to a dopant (or an emitter).

[0135] For example, phosphorescence or fluorescence emitted from the dopant (or the emitter) in the second embodiment may be blue phosphorescence or blue fluorescence (e.g., blue delayed fluorescence).

[0136] The dopant (or the emitter) in the second embodiment may be a phosphorescent dopant material (e.g., the organometallic compound represented by Formula 1, an organometallic compound represented by Formula 401, or any combination thereof) or any fluorescent dopant material (e.g., a compound represented by Formula 501, the compound represented by Formula 502, the compound represented by Formula 503, or any combination thereof).

[0137] In the first embodiment and the second embodiment, the blue light may be blue light having a maximum emission wavelength in a range of about 390 nm to about 500 nm, about 410 nm to about 490 nm, about 430 nm to about 480 nm, about 440 nm to about 475 nm, or about 455 nm to about 470 nm.

[0138] The auxiliary dopant in the first embodiment may include, for example, the compound represented by Formula 502 or Formula 503 as the fourth compound.

[0139] In one or more embodiments, the host in the first embodiment and the second embodiment may be any host material (e.g., a compound represented by Formula 301, a compound represented by 301-1, a compound represented by Formula 301-2, or any combination thereof).

[0140] In one or more embodiments, the host in the first embodiment and the second embodiment may be the second compound, the third compound, or any combination thereof.

[0141] In one or more embodiments, the light-emitting device may further include a capping layer located outside (e.g., on) the first electrode and/or outside (e.g., on) the second electrode.

[0142] In one or more embodiments, the light-emitting device may further include at least one of a first capping layer located outside (e.g., on) the first electrode or a second capping layer located outside (e.g., on) the second electrode, at least one of the first capping layer or the second capping layer may (e.g., the first capping layer and the second capping layer may each independently) include the organometallic compound represented by Formula 1. A more detailed description of the first capping layer and/or the second capping layer may be referred by descriptions provided elsewhere herein.

[0143] In one or more embodiments, the light-emitting device may include: [0144] a first capping layer located outside (e.g., on) the first electrode and including the organometallic compound represented by Formula 1; [0145] a second capping layer located outside (e.g., on) the second electrode and including the organometallic compound represented by Formula 1; or [0146] both (e.g., simultaneously) the first capping layer and the second capping layer.

[0147] The wording (interlayer and/or capping layer) includes an organometallic compound represented by Formula 1 as utilized herein may be understood as (interlayer and/or capping layer) may include one kind of organometallic compound represented by Formula 1 or two different kinds of organometallic compounds, each represented by Formula 1.

[0148] In one or more embodiments, the interlayer and/or the capping layer may include Compound 1 only as the organometallic compound. Here, Compound 1 may be present in the emission layer of the light-emitting device. In one or more embodiments, the interlayer may include, as the organometallic compound, Compound 1 and Compound 2. In this regard, Compound 1 and Compound 2 may be present in substantially the same layer (for example, both (e.g., simultaneously) Compound 1 and Compound 2 may be present in the emission layer), or may be present in different layers (for example, Compound 1 may be present in the emission layer, and Compound 2 may be present in the electron transport region).

[0149] The term interlayer as utilized herein refers to a single layer and/or all of multiple layers between the first electrode and the second electrode of the light-emitting device.

[0150] According to one or more embodiments of the present disclosure, an electronic apparatus may include the light-emitting device. In one or more embodiments, the electronic apparatus may further include a thin-film transistor. For example, in some embodiments, the electronic apparatus may further include a thin-film transistor including a source electrode and a drain electrode, and the first electrode of the light-emitting device may be electrically connected to the source electrode or the drain electrode of the thin-film transistor. In one or more embodiments, the electronic apparatus may further include a color filter, a color conversion layer, a touch screen layer, a polarizing layer, or any combination thereof. A more detailed description of the electronic apparatus may be referred by descriptions provided elsewhere herein.

[0151] According to one or more embodiments of the present disclosure, electronic equipment may include the light-emitting device.

[0152] For example, the electronic equipment may be at least one of a flat panel display, a curved display, a computer monitor, a medical monitor, a television, a billboard, an indoor or outdoor light and/or light for signal, a head-up display, a fully or partially transparent display, a flexible display, a rollable display, a foldable display, a stretchable display, a laser printer, a telephone, a portable phone, a tablet personal computer, a phablet, a personal digital assistant (PDA), a wearable device, a laptop computer, a digital camera, a camcorder, a viewfinder, a micro display, a three-dimensional (3D) display, a virtual reality or augmented reality display, a vehicle, a video wall with multiple displays tiled together, a theater or stadium screen, a phototherapy device, or a signboard.

[0153] According to one or more embodiments of the present disclosure, provided is the organometallic compound represented by Formula 1. A description of Formula 1 may be the same as described herein.

[0154] Synthesis methods of the organometallic compound may be recognizable by one of ordinary skill in the art by referring to Synthesis Examples and/or Examples provided herein.

Descriptions on Formulae 1, 2-1, and 2-2

##STR00010##

[0155] In Formula 1, M may be platinum (Pt), palladium (Pd), copper (Cu), silver (Ag), gold (Au), rhodium (Rh), ruthenium (Ru), osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu), terbium (Tb), or thulium (Tm).

[0156] In one or more embodiments, M may be Pt, Pd, or Au.

[0157] In one or more embodiments, M may be Pt.

[0158] In Formula 1, X.sub.11, X.sub.12, and X.sub.2 to X.sub.4 may each independently be C or N.

[0159] In one or more embodiments, X.sub.11 may be C.

[0160] In one or more embodiments, X.sub.11 may be C, and a bond between X.sub.11 and M may be a coordinate bond.

[0161] In one or more embodiments, X.sub.11 may be C of a carbene moiety.

[0162] In one or more embodiments, X.sub.2 and X.sub.3 may each be C, and X.sub.4 may be N.

[0163] In one or more embodiments, i) a bond between X.sub.11 and M may be a coordinate bond, and ii) one bond selected from among a bond between X.sub.2 and M, a bond between X.sub.3 and M, and a bond between X.sub.4 and M may be a coordinate bond, and the other two bonds may each be a covalent bond.

[0164] In one or more embodiments, a bond between X.sub.11 and M and a bond between X.sub.4 and M may each be a coordinate bond, and a bond between X.sub.2 and M and a bond between X.sub.3 and M may each be a covalent bond.

[0165] In one or more embodiments, X.sub.11, X.sub.2, and X.sub.3 may each be C, and X.sub.4 may be N, [0166] a bond between X.sub.11 and M and a bond between X.sub.4 and M may each be a coordinate bond, and [0167] a bond between X.sub.2 and M and a bond between X.sub.3 and M may each be a covalent bond.

[0168] In one or more embodiments, X.sub.12 may be N.

[0169] In Formula 1, ring CY.sub.1 to ring CY.sub.4 may each independently be a C.sub.5-C.sub.30 carbocyclic group or a C.sub.1-C.sub.30 heterocyclic group.

[0170] In one or more embodiments, ring CY.sub.1 to ring CY.sub.4 may each independently be: [0171] a benzene group, a naphthalene group, an anthracene group, a phenanthrene group, a triphenylene group, a pyrene group, a chrysene group, a cyclopentadiene group, a furan group, a thiophene group, a silole group, an indene group, a fluorene group, an indole group, a carbazole group, a benzofuran group, a dibenzofuran group, a benzothiophene group, a dibenzothiophene group, a benzosilole group, a dibenzosilole group, an azafluorene group, an azacarbazole group, an azadibenzofuran group, an azadibenzothiophene group, an azadibenzosilole group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, a quinoline group, an isoquinoline group, a quinoxaline group, a quinazoline group, a phenanthroline group, a pyrrole group, a pyrazole group, an imidazole group, a triazole group, an oxazole group, an isoxazole group, a thiazole group, an isothiazole group, a oxadiazole group, a thiadiazole group, a benzopyrazole group, a benzimidazole group, a benzoxazole group, a benzothiazole group, a benzoxadiazole group, a benzothiadiazole group, a dibenzoxasiline group, a dibenzothiasiline group, a dibenzodihydroazasiline group, a dibenzodihydrodisiline group, a dibenzodihydrosiline group, a dibenzodioxin group, dibenzoxathine group, a dibenzoxazine group, a dibenzopyran group, a dibenzodithine group, a dibenzothiazine group, a dibenzothiopyran group, a dibenzocyclohexadiene group, a dibenzodihydropyridine group, or a dibenzodihydropyrazine group.

[0172] In one or more embodiments, ring CY.sub.1 may be a nitrogen-containing C.sub.1-C.sub.60 heterocyclic group.

[0173] In one or more embodiments, ring CY.sub.1 may be an imidazole group, a triazole group, a benzimidazole group, a naphthoimidazole group, or an imidazopyridine group.

[0174] In one or more embodiments, X.sub.11 may be C, and [0175] ring CY.sub.1 may be an imidazole group, a triazole group, a benzimidazole group, a naphthoimidazole group, or an imidazopyridine group.

[0176] In one or more embodiments, X.sub.11 may be C of a carbene moiety, and [0177] ring CY.sub.1 may be an imidazole group, a triazole group, a benzimidazole group, a naphthoimidazole group, or an imidazopyridine group.

[0178] In one or more embodiments, ring CY.sub.2 may be a benzene group, a pyridine group, a pyrimidine group, a naphthalene group, a dibenzofuran group, a dibenzothiophene group, a carbazole group, a fluorene group, a dibenzosilole group, a naphthobenzofuran group, a naphthobenzothiophene group, a benzocarbazole group, a benzofluorene group, a naphthobenzosilole group, a dinaphthofuran group, a dinaphthothiophene group, a dibenzocarbazole group, a dibenzofluorene group, a dinaphthosilole group, an azadibenzofuran group, an azadibenzothiophene group, an azacarbazole group, an azafluorene group, an azadibenzosilole group, an azanaphthobenzofuran group, an azanaphthobenzothiophene group, an azabenzocarbazole group, an azabenzofluorene group, an azanaphthobenzosilole group, an azadinaphthofuran group, an azadinaphthothiophene group, an azadibenzocarbazole group, an azadibenzofluorene group, or an azadinaphthosilole group.

[0179] In one or more embodiments, ring CY.sub.2 may be a benzene group, a pyridine group, a pyrimidine group, a naphthalene group, a dibenzofuran group, a dibenzothiophene group, a carbazole group, a fluorene group, or a dibenzosilole group.

[0180] In one or more embodiments, ring CY.sub.3 may be: a C.sub.2-C.sub.8 monocyclic group; or a C.sub.4-C.sub.20 polycyclic group in which 2 or 3 C.sub.2-C.sub.8 monocyclic groups are condensed with each other.

[0181] In one or more embodiments, ring CY.sub.3 may be a benzene group, a pyridine group, a pyrimidine group, a naphthalene group, a dibenzofuran group, a dibenzothiophene group, a carbazole group, a fluorene group, a dibenzosilole group, an azadibenzofuran group, an azadibenzothiophene group, an azacarbazole group, an azafluorene group, or an azadibenzosilole group.

[0182] In one or more embodiments, ring CY.sub.4 may be a nitrogen-containing C.sub.1-C.sub.60 heterocyclic group.

[0183] In one or more embodiments, ring CY.sub.4 may be a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, a quinoline group, an isoquinoline group, a quinoxaline group, a quinazoline group, a phenanthroline group, a pyrrole group, a pyrazole group, an imidazole group, a triazole group, a benzopyrazole group, a benzimidazole group, or a benzothiazole group.

[0184] In Formula 1, L.sub.1 to Ls may each independently be a single bond, *C(R.sub.1a)(R.sub.1b)*, *C(R.sub.1a)*, *C(R.sub.1a)*, *C(R.sub.1a)C(R.sub.1b)*, *C(O)*, *C(S)*, *CC*, *B(R.sub.1a)*, *N(R.sub.1a)*, *O*, *P(R.sub.1a)*, *Al(R.sub.1a)*, *Si(R.sub.1a)(R.sub.1b)*, *P(O)(R.sub.1a)*, *S*, *S(O)*, *S(O).sub.2*, or *Ge(R.sub.1a)(R.sub.1b)*, wherein * and * each indicate a binding site to a neighboring atom,

[0185] In Formula 1, n1 to n3 indicate the number of L.sub.1(s) to the number of L.sub.3(s), respectively, and may each be an integer from 1 to 5. When n1 is 2 or more, two or more L.sub.1(s) may be identical to or different from each other, when n2 is 2 or more, two or more L.sub.2(s) may be identical to or different from each other, and when n3 is 2 or more, two or more L.sub.3(s) may be identical to or different from each other.

[0186] In one or more embodiments, R.sub.1a and R.sub.1b may each independently be: [0187] hydrogen, deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.20 alkyl group, or a C.sub.1-C.sub.20 alkoxy group; [0188] a C.sub.1-C.sub.20 alkyl group or a C.sub.1-C.sub.20 alkoxy group, each substituted with deuterium, F, Cl, Br, I, CD.sub.3, CD.sub.2H, CDH.sub.2, CF.sub.3, CF.sub.2H, CFH.sub.2, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.10 alkyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a naphthyl group, a pyridinyl group, a pyrimidinyl group, or any combination thereof; [0189] a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a (C.sub.1-C.sub.10 alkyl)phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group, a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a benzothiazolyl group, a benzoisoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, an azacarbazolyl group, an azadibenzofuranyl group, an azadibenzothiophenyl group, an azafluorenyl group, or an azadibenzosilolyl group, each unsubstituted or substituted with deuterium, F, Cl, Br, I, CD.sub.3, CD.sub.2H, CDH.sub.2, CF.sub.3, CF.sub.2H, CFH.sub.2, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a (C.sub.1-C.sub.10 alkyl)phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group, a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a benzoisothiazolyl group, a benzoxazolyl group, a benzoisoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, O(Q.sub.31), S(Q.sub.31), Si(Q.sub.31)(Q.sub.32)(Q.sub.33), N(Q.sub.31)(Q.sub.32), B(Q.sub.31)(Q.sub.32), P(Q.sub.31)(Q.sub.32), C(O)(Q.sub.31), S(O).sub.2(Q.sub.31), P(O)(Q.sub.31)(Q.sub.32), or any combination thereof; or [0190] C(Q.sub.1)(Q.sub.2)(Q.sub.3), Si(Q.sub.1)(Q.sub.2)(Q.sub.3), N(Q.sub.1)(Q.sub.2), B(Q.sub.1)(Q.sub.2), C(O)(Q.sub.1), S(O).sub.2(Q.sub.1), or P(O)(Q.sub.1)(Q.sub.2), and [0191] Q.sub.1 to Q.sub.3 and Q.sub.31 to Q.sub.33 may each independently be: hydrogen; deuterium; F; Cl; Br; I; a hydroxyl group; a cyano group; a nitro group; a C.sub.1-C.sub.60 alkyl group; a C.sub.2-C.sub.60 alkenyl group; a C.sub.2-C.sub.60 alkynyl group; a C.sub.1-C.sub.60 alkoxy group; or a C.sub.3-C.sub.60 carbocyclic group or a C.sub.1-C.sub.60 heterocyclic group, each unsubstituted or substituted with deuterium, F, a cyano group, a C.sub.1-C.sub.60 alkyl group, a C.sub.1-C.sub.60 alkoxy group, a phenyl group, a biphenyl group, or any combination thereof.

[0192] In one or more embodiments, L.sub.1 and L.sub.3 may each be a single bond.

[0193] In one or more embodiments, L.sub.2 may be *O* or *S*, and n2 may be 1.

[0194] In one or more embodiments, L.sub.1 and L.sub.3 may each be a single bond, and L.sub.2 may be *O* or *S*, and n2 may be 1.

[0195] In Formula 1, R.sub.1 to R.sub.4, R.sub.1a, and R.sub.1b may each independently be hydrogen, deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.60 alkyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkenyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkynyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 alkoxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 alkylthio group unsubstituted or substituted with at least one R.sub.10a, a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.6-C.sub.60 aryloxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.6-C.sub.60 arylthio group unsubstituted or substituted with at least one R.sub.10a, C(Q.sub.1)(Q.sub.2)(Q.sub.3), Si(Q.sub.1)(Q.sub.2)(Q.sub.3), N(Q.sub.1)(Q.sub.2), B(Q.sub.1)(Q.sub.2), C(O)(Q.sub.1), S(O).sub.2(Q.sub.1), or P(O)(Q.sub.1)(Q.sub.2). [0196] R.sub.10a and Q.sub.1 to Qs may each be the same as described herein.

[0197] In Formula 1, a1 to a4 may each independently be an integer from 1 to 20.

[0198] In one or more embodiments, R.sub.1 to R.sub.4 may each independently be: [0199] hydrogen, deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.20 alkyl group, or a C.sub.1-C.sub.20 alkoxy group; [0200] a C.sub.1-C.sub.20 alkyl group or a C.sub.1-C.sub.20 alkoxy group, each substituted with deuterium, F, Cl, Br, I, CD.sub.3, CD.sub.2H, CDH.sub.2, CF.sub.3, CF.sub.2H, CFH.sub.2, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.10 alkyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a naphthyl group, a pyridinyl group, a pyrimidinyl group, or any combination thereof; [0201] a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a (C.sub.1-C.sub.10 alkyl)phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group, a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a benzothiazolyl group, a benzoisoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, an azacarbazolyl group, an azadibenzofuranyl group, an azadibenzothiophenyl group, an azafluorenyl group, or an azadibenzosilolyl group, each unsubstituted or substituted with deuterium, F, Cl, Br, I, CD.sub.3, CD.sub.2H, CDH.sub.2, CF.sub.3, CF.sub.2H, CFH.sub.2, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a (C.sub.1-C.sub.10 alkyl)phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group, a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a benzoisothiazolyl group, a benzoxazolyl group, a benzoisoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, O(Q.sub.31), S(Q.sub.31), Si(Q.sub.31)(Q.sub.32)(Q.sub.33), N(Q.sub.31)(Q.sub.32), B(Q.sub.31)(Q.sub.32), P(Q.sub.31)(Q.sub.32), C(O)(Q.sub.31), S(O).sub.2(Q.sub.31), P(O)(Q.sub.31)(Q.sub.32), or any combination thereof; or [0202] C(Q.sub.1)(Q.sub.2)(Q.sub.3), Si(Q.sub.1)(Q.sub.2)(Q.sub.3), N(Q.sub.1)(Q.sub.2), B(Q.sub.1)(Q.sub.2), C(O)(Q.sub.1), S(O).sub.2(Q.sub.1), or P(O)(Q.sub.1)(Q.sub.2), and [0203] Q.sub.1 to Q.sub.3 and Q.sub.31 to Q.sub.33 may each independently be: hydrogen; deuterium; F; Cl; Br; I; a hydroxyl group; a cyano group; a nitro group; a C.sub.1-C.sub.60 alkyl group; a C.sub.2-C.sub.60 alkenyl group; a C.sub.2-C.sub.60 alkynyl group; a C.sub.1-C.sub.60 alkoxy group; or a C.sub.3-C.sub.60 carbocyclic group or a C.sub.1-C.sub.60 heterocyclic group, each unsubstituted or substituted with deuterium, F, a cyano group, a C.sub.1-C.sub.60 alkyl group, a C.sub.1-C.sub.60 alkoxy group, a phenyl group, a biphenyl group, or any combination thereof.

[0204] In one or more embodiments, R.sub.1 to R.sub.4 may each independently be: [0205] hydrogen, deuterium, F, Cl, Br, I, or a C.sub.1-C.sub.20 alkyl group; [0206] a C.sub.1-C.sub.20 alkyl group substituted with deuterium, F, Cl, Br, I, CD.sub.3, CD.sub.2H, CDH.sub.2, CF.sub.3, CF.sub.2H, CFH.sub.2, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.10 alkyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a naphthyl group, a pyridinyl group, a pyrimidinyl group, or any combination thereof; or [0207] a phenyl group, a biphenyl group, a terphenyl group, a (C.sub.1-C.sub.10 alkyl)phenyl group, or a naphthyl group, each unsubstituted or substituted with deuterium, F, Cl, Br, I, CD.sub.3, CD.sub.2H, CDH.sub.2, CF.sub.3, CF.sub.2H, CFH.sub.2, a C.sub.1-C.sub.20 alkyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a naphthyl group, a pyridinyl group, a pyrimidinyl group, a (C.sub.1-C.sub.10 alkyl)phenyl group, or any combination thereof.

[0208] In Formula 1, Ar.sub.1 may be a group represented by Formula 2-1 or 2-2.

[0209] In one or more embodiments, when a1 is 2 or more, two or more of R.sub.1(s) in the number of a1 may optionally be bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a.

[0210] In one or more embodiments, when a2 is 2 or more, two or more of R.sub.2(s) in the number of a2 may optionally be bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a.

[0211] In one or more embodiments, when a3 is 2 or more, two or more of R.sub.3(s) in the number of a3 may optionally be bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a.

[0212] In one or more embodiments, when a4 is 2 or more, two or more of R.sub.4(s) in the number of a4 may optionally be bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a.

[0213] In one or more embodiments, R.sub.1a and R.sub.1b may optionally be bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a.

[0214] In one or more embodiments, two or more selected from among R.sub.1 to R.sub.4, R.sub.1a, R.sub.1b, and Ar.sub.1 may optionally be bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a.

[0215] In one or more embodiments, a group represented by

##STR00011##

in Formula 1 may be a group represented by one selected from among Formulae CY1(1) to CY1(11):

##STR00012## ##STR00013## [0216] wherein, in Formulae CY1(1) to CY1(11), [0217] Ar.sub.1 may be the same as described herein, [0218] R.sub.11 to R.sub.18 may each be the same as described with respect to R.sub.1, [0219] * indicates a binding site to M in Formula 1, and [0220] * indicates a binding site to L.sub.1 in Formula 1.

[0221] In one or more embodiments, a group represented by

##STR00014##

in Formula 1 may be a group represented by one selected from among Formulae CY2(1) to CY2(13):

##STR00015## ##STR00016## [0222] wherein, in Formulae CY2(1) to CY2(13), [0223] T.sub.21 may be B(Y.sub.21), C(Y.sub.21)(Y.sub.22), N(Y.sub.21), O, S, or Si(Y.sub.21)(Y.sub.22), [0224] T.sub.22 may be C(Y.sub.21), N, or Si(Y.sub.21), [0225] R.sub.21 to R.sub.26, Y.sub.21, and Y.sub.22 may each be the same as described with respect to R.sub.2, [0226] * indicates a binding site to M in Formula 1, [0227] * indicates a binding site to L.sub.1 in Formula 1, and [0228] * indicates a binding site to L.sub.2 in Formula 1.

[0229] In one or more embodiments, a group represented by

##STR00017##

in Formula 1 may be a group represented by one selected from among Formulae CY3(1) to CY3(25):

##STR00018## ##STR00019## ##STR00020## ##STR00021## ##STR00022## [0230] wherein, in Formulae CY3(1) to CY3(25), [0231] T.sub.31 may be B(Y.sub.31), C(Y.sub.31)(Y.sub.32), N(Y.sub.31), O, S, or Si(Y.sub.31)(Y.sub.32), [0232] T.sub.32 may be C(Y.sub.31), N, or Si(Y.sub.31), [0233] R.sub.31 to R.sub.35, Y.sub.31, and Y.sub.32 may each be the same as described with respect to R.sub.3, [0234] * indicates a binding site to M in Formula 1, [0235] * indicates a binding site to L.sub.2 in Formula 1, and [0236] * indicates a binding site to L.sub.3 in Formula 1.

[0237] In one or more embodiments, a group represented by

##STR00023##

in Formula 1 may be a group represented by one selected from among Formulae CY4(1) to CY4(29):

##STR00024## ##STR00025## ##STR00026## ##STR00027## ##STR00028## [0238] wherein, in Formulae CY4(1) to CY4(29), [0239] R.sub.41 to R.sub.47 may each be the same as described with respect to R.sub.4, [0240] * indicates a binding site to M in Formula 1, and [0241] * indicates a binding site to Ls in Formula 1.

##STR00029##

[0242] In Formulae 2-1 and 2-2, Y.sub.1 and Y.sub.2 may each independently be B or N, wherein Y.sub.1 and Y.sub.2 may be different from each other.

[0243] In one or more embodiments, i) Y.sub.1 may be B, and Y.sub.2 may be N, or ii) Y.sub.1 may be N, and Y.sub.2 may be B.

[0244] In one or more embodiments, Y.sub.1 may be N, and Y.sub.2 may be B.

[0245] In one or more embodiments, Y.sub.1 may be B, and Y.sub.2 may be N.

[0246] In Formulae 2-1 and 2-2, Z.sub.1 to Z.sub.7 may each independently be hydrogen, deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.60 alkyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkenyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkynyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 alkoxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 alkylthio group unsubstituted or substituted with at least one R.sub.10a, a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.6-C.sub.60 aryloxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.6-C.sub.60 arylthio group unsubstituted or substituted with at least one R.sub.10a, C(Q.sub.1)(Q.sub.2)(Q.sub.3), Si(Q.sub.1)(Q.sub.2)(Q.sub.3), N(Q.sub.1)(Q.sub.2), B(Q.sub.1)(Q.sub.2), C(O)(Q.sub.1), S(O).sub.2(Q.sub.1), or P(O)(Q.sub.1)(Q.sub.2).

[0247] R.sub.10a and Q.sub.1 to Q.sub.3 may each be the same as described herein.

[0248] In one or more embodiments, Z.sub.1 to Z.sub.7 may each independently be: [0249] hydrogen, deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.20 alkyl group, or a C.sub.1-C.sub.20 alkoxy group; [0250] a C.sub.1-C.sub.20 alkyl group or a C.sub.1-C.sub.20 alkoxy group, each substituted with deuterium, F, Cl, Br, I, CD.sub.3, CD.sub.2H, CDH.sub.2, CF.sub.3, CF.sub.2H, CFH.sub.2, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.10 alkyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a naphthyl group, a pyridinyl group, a pyrimidinyl group, or any combination thereof; [0251] a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a (C.sub.1-C.sub.10 alkyl)phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group, a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a benzothiazolyl group, a benzoisoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, an azacarbazolyl group, an azadibenzofuranyl group, an azadibenzothiophenyl group, an azafluorenyl group, or an azadibenzosilolyl group, each unsubstituted or substituted with deuterium, F, Cl, Br, I, CD.sub.3, CD.sub.2H, CDH.sub.2, CF.sub.3, CF.sub.2H, CFH.sub.2, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a (C.sub.1-C.sub.10 alkyl)phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group, a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a benzoisothiazolyl group, a benzoxazolyl group, a benzoisoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, O(Q.sub.31), S(Q.sub.31), Si(Q.sub.31)(Q.sub.32)(Q.sub.33), N(Q.sub.31)(Q.sub.32), B(Q.sub.31)(Q.sub.32), P(Q.sub.31)(Q.sub.32), C(O)(Q.sub.31), S(O).sub.2(Q.sub.31), P(O)(Q.sub.31)(Q.sub.32), or any combination thereof; or [0252] C(Q.sub.1)(Q.sub.2)(Q.sub.3), Si(Q.sub.1)(Q.sub.2)(Q.sub.3), N(Q.sub.1)(Q.sub.2), B(Q.sub.1)(Q.sub.2), C(O)(Q.sub.1), S(O).sub.2(Q.sub.1), or P(O)(Q.sub.1)(Q.sub.2), and [0253] Q.sub.1 to Q.sub.3 and Q.sub.31 to Q.sub.33 may each independently be: hydrogen; deuterium; F; Cl; Br; I; a hydroxyl group; a cyano group; a nitro group; a C.sub.1-C.sub.60 alkyl group; a C.sub.2-C.sub.60 alkenyl group; a C.sub.2-C.sub.60 alkynyl group; a C.sub.1-C.sub.60 alkoxy group; or a C.sub.3-C.sub.60 carbocyclic group or a C.sub.1-C.sub.60 heterocyclic group, each unsubstituted or substituted with deuterium, F, a cyano group, a C.sub.1-C.sub.60 alkyl group, a C.sub.1-C.sub.60 alkoxy group, a phenyl group, a biphenyl group, or any combination thereof.

[0254] In one or more embodiments, Z.sub.1 to Z.sub.7 may each independently be: [0255] hydrogen, deuterium, F, Cl, Br, I, or a C.sub.1-C.sub.20 alkyl group; [0256] a C.sub.1-C.sub.20 alkyl group substituted with deuterium, F, Cl, Br, I, CD.sub.3, CD.sub.2H, CDH.sub.2, CF.sub.3, CF.sub.2H, CFH.sub.2, a cyano group, a C.sub.1-C.sub.10 alkyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a naphthyl group, a pyridinyl group, a pyrimidinyl group, or any combination thereof; or [0257] a phenyl group, a biphenyl group, a terphenyl group, a (C.sub.1-C.sub.10 alkyl)phenyl group, or a naphthyl group, each unsubstituted or substituted with deuterium, F, Cl, Br, I, CD.sub.3, CD.sub.2H, CDH.sub.2, CF.sub.3, CF.sub.2H, CFH.sub.2, a C.sub.1-C.sub.20 alkyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a naphthyl group, a pyridinyl group, a pyrimidinyl group, a (C.sub.1-C.sub.10 alkyl)phenyl group, or any combination thereof.

[0258] In one or more embodiments, at least one selected from among Z.sub.1 to Z.sub.7 may not be hydrogen.

[0259] In one or more embodiments, at least two selected from among Z.sub.1 to Z.sub.7 may not be hydrogen.

[0260] In one or more embodiments, Z.sub.1 and Z.sub.2 in Formula 2-1 may not be hydrogen, and Z.sub.1 and Z.sub.6 in Formula 2-2 may not be hydrogen.

[0261] In one or more embodiments, at least one selected from among Z.sub.1 to Z.sub.7 may include deuterium.

[0262] In Formulae 2-1 and 2-2, * indicates a binding site to X.sub.12 in Formula 1.

[0263] In one or more embodiments, two or more selected from among Z.sub.1 to Z.sub.7 may optionally be bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a.

[0264] In one or more embodiments, the organometallic compound represented by Formula 1 may be represented by Formula 1-1 or 1-2:

##STR00030## [0265] wherein, in Formulae 1-1 and 1-2, [0266] M, Y.sub.1, Y.sub.2, and Z.sub.1 to Z.sub.7 may each be the same as described herein, [0267] L.sub.2 may be *O* or *S*, [0268] X.sub.13 may be C(R.sub.13) or N, X.sub.14 may be C(R.sub.14) or N, X.sub.15 may be C(R.sub.15) or N, and X.sub.16 may be C(R.sub.16) or N, [0269] X.sub.21 may be C(R.sub.21) or N, X.sub.22 may be C(R.sub.22) or N, and X.sub.23 may be C(R.sub.23) or N, [0270] X.sub.31 may be C(R.sub.31) or N, X.sub.32 may be C(R.sub.32) or N, X.sub.33 may be C(R.sub.33) or N, X.sub.34 may be C(R.sub.34) or N, X.sub.35 may be C(R.sub.35) or N, and X.sub.36 may be C(R.sub.36) or N, [0271] X.sub.41 may be C(R.sub.41) or N, X.sub.42 may be C(R.sub.42) or N, X.sub.43 may be C(R.sub.43) or N, and X.sub.44 may be C(R.sub.44) or N, [0272] R.sub.13 to R.sub.16 may each be the same as described with respect to R.sub.1, [0273] R.sub.21 to R.sub.23 may each be the same as described with respect to R.sub.2, [0274] R.sub.31 to R.sub.36 may each be the same as described with respect to R.sub.3, [0275] R.sub.41 to R.sub.44 may each be the same as described with respect to R.sub.4, [0276] two or more selected from among R.sub.13 to R.sub.16 may optionally be bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, [0277] two or more selected from among R.sub.21 to R.sub.23 may optionally be bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, [0278] two or more selected from among R.sub.31 to R.sub.36 may optionally be bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, [0279] two or more selected from among R.sub.41 to R.sub.44 may optionally be bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, [0280] two or more selected from among R.sub.13 to R.sub.16, R.sub.21 to R.sub.23, R.sub.31 to R.sub.36, R.sub.41 to R.sub.44, and Z.sub.1 to Z.sub.7 may optionally be bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, [0281] two or more selected from among Z.sub.1 to Z.sub.7 may optionally be bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, and [0282] R.sub.10a may be the same as described herein.

[0283] Unless otherwise defined herein, for example, in one or more embodiments, R.sub.10a in Formulae 1, 2-1, and 2-2 may be: [0284] deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, or a nitro group; [0285] a C.sub.1-C.sub.60 alkyl group, a C.sub.2-C.sub.60 alkenyl group, a C.sub.2-C.sub.60 alkynyl group, or a C.sub.1-C.sub.60 alkoxy group, each unsubstituted or substituted with deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, a nitro group, a C.sub.3-C.sub.60 carbocyclic group, a C.sub.1-C.sub.60 heterocyclic group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.7-C.sub.60 arylalkyl group, a C.sub.2-C.sub.60 heteroarylalkyl group, Si(Q.sub.11)(Q.sub.12)(Q.sub.13), N(Q.sub.11)(Q.sub.12), B(Q.sub.11)(Q.sub.12), C(O)(Q.sub.11), S(O).sub.2(Q.sub.11), P(O)(Q.sub.11)(Q.sub.12), or any combination thereof; [0286] a C.sub.3-C.sub.60 carbocyclic group, a C.sub.1-C.sub.60 heterocyclic group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.7-C.sub.60 arylalkyl group, or a C.sub.2-C.sub.60 heteroarylalkyl group, each unsubstituted or substituted with deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.60 alkyl group, a C.sub.2-C.sub.60 alkenyl group, a C.sub.2-C.sub.60 alkynyl group, a C.sub.1-C.sub.60 alkoxy group, a C.sub.3-C.sub.60 carbocyclic group, a C.sub.1-C.sub.60 heterocyclic group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.7-C.sub.60 arylalkyl group, a C.sub.2-C.sub.60 heteroarylalkyl group, Si(Q.sub.21)(Q.sub.22)(Q.sub.23), N(Q.sub.21)(Q.sub.22), B(Q.sub.21)(Q.sub.22), C(O)(Q.sub.21), S(O).sub.2(Q.sub.21), P(O)(Q.sub.21)(Q.sub.22), or any combination thereof; or [0287] Si(Q.sub.31)(Q.sub.32)(Q.sub.33), N(Q.sub.31)(Q.sub.32), B(Q.sub.31)(Q.sub.32), C(O)(Q.sub.31), S(O).sub.2(Q.sub.31), or P(O)(Q.sub.31)(Q.sub.32).

[0288] Unless otherwise defined herein, for example, Q.sub.1 to Q.sub.3, Q.sub.11 to Q.sub.13, Q.sub.21 to Q.sub.23, and Q.sub.31 to Q.sub.33 in Formulae 1, 2-1, and 2-2 may each independently be: hydrogen; deuterium; F; Cl; Br; I; a hydroxyl group; a cyano group; a nitro group; a C.sub.1-C.sub.60 alkyl group; a C.sub.2-C.sub.60 alkenyl group; a C.sub.2-C.sub.60 alkynyl group; a C.sub.1-C.sub.60 alkoxy group; or a C.sub.3-C.sub.60 carbocyclic group, a C.sub.1-C.sub.60 heterocyclic group, a C.sub.7-C.sub.60 arylalkyl group, or a C.sub.2-C.sub.60 heteroarylalkyl group, each unsubstituted or substituted with deuterium, F, cyano group, a C.sub.1-C.sub.60 alkyl group, a C.sub.1-C.sub.60 alkoxy group, a phenyl group, a biphenyl group, or any combination thereof.

[0289] When Ar.sub.1 in the organometallic compound represented by Formula 1 is the group represented by Formula 2-1 or 2-2, the blue shift of the maximum emission wavelength may occur, the Huang-Rhys Factor (HRF) may decrease, and the existence ratio of triplet metal-to-ligand charge transfer state (.sup.3MLCT) may increase. As the maximum emission wavelength is blue-shifted, the color coordinates of the organometallic compound represented by Formula 1 may be improved. In addition, as the HRF decreases and the existence ratio of .sup.3MLCT increases, non-luminescent transitions may be suppressed or reduced and the quantum efficiency may be improved, thereby improving the luminescence efficiency. Therefore, when the organometallic compound represented by Formula 1 is utilized in an electronic device (e.g., an organic light-emitting device, and for example, in an emission layer of an organic light-emitting device) the color purity and efficiency may be improved and the lifespan may increase.

Descriptions of Other Chemical Formulae

##STR00031##

[0290] In Formula 2, L.sub.51 to L.sub.53 may each independently be a single bond, a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a.

[0291] In Formula 2, b51 to b53 indicate the number of L.sub.51(s) to the number of L.sub.53(s), respectively, and may each be an integer from 1 to 5. When b51 is 2 or more, two or more L.sub.51(s) may be identical to or different from each other, when b52 is 2 or more, two or more L.sub.52(s) may be identical to or different from each other, and when b53 is 2 or more, two or more L.sub.53(s) may be identical to or different from each other. In some embodiments, b51 to b53 may each independently be 1 or 2.

[0292] In one or more embodiments, in Formula 2, L.sub.51 to L.sub.53 may each independently be: [0293] a single bond; or [0294] a benzene group, a naphthalene group, an anthracene group, a phenanthrene group, a triphenylene group, a pyrene group, a chrysene group, a cyclopentadiene group, a furan group, a thiophene group, a silole group, an indene group, a fluorene group, an indole group, a carbazole group, a benzofuran group, a dibenzofuran group, a benzothiophene group, a dibenzothiophene group, a benzosilole group, a dibenzosilole group, an azafluorene group, an azacarbazole group, an azadibenzofuran group, an azadibenzothiophene group, an azadibenzosilole group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, a quinoline group, an isoquinoline group, a quinoxaline group, a quinazoline group, a phenanthroline group, a pyrrole group, a pyrazole group, an imidazole group, a triazole group, an oxazole group, an isooxazole group, a thiazole group, an isothiazole group, an oxadiazole group, a thiadiazole group, a benzopyrazole group, a benzimidazole group, a benzoxazole group, a benzothiazole group, a benzoxadiazole group, a benzothiadiazole group, a dibenzoxasiline group, a dibenzothiasiline group, a dibenzodihydroazasiline group, a dibenzodihydrodisiline group, a dibenzodihydrosiline group, a dibenzodioxin group, a dibenzooxathiine group, a dibenzooxazine group, a dibenzopyran group, a dibenzodithiine group, a dibenzothiazine group, a dibenzothiopyran group, a dibenzocyclohexadiene group, a dibenzodihydropyridine group, or a dibenzodihydropyrazine group, each unsubstituted or substituted with deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a naphthyl group, a pyridinyl group, a pyrimidinyl group, a triazinyl group, a fluorenyl group, a dimethylfluorenyl group, a diphenyl fluorenyl group, a carbazolyl group, a phenylcarbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a dibenzosilolyl group, a dimethyldibenzosilolyl group, a diphenyldibenzosilolyl group, O(Q.sub.31), S(Q.sub.31), Si(Q.sub.31)(Q.sub.32)(Q.sub.33), N(Q.sub.31)(Q.sub.32), B(Q.sub.31)(Q.sub.32), P(Q.sub.31)(Q.sub.32), C(O)(Q.sub.31), S(O).sub.2(Q.sub.31), P(O)(Q.sub.31)(Q.sub.32), or any combination thereof, and [0295] Q.sub.31 to Q.sub.33 may each independently be hydrogen, deuterium, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a pyridinyl group, a pyrimidinyl group, a pyridazinyl group, a pyrazinyl group, or a triazinyl group.

[0296] In one or more embodiments, in Formula 2, a bond between L.sub.51 and R.sub.51, a bond between L.sub.52 and R.sub.52, a bond between L.sub.53 and R.sub.53, a bond between two L.sub.51(s), a bond between two L.sub.52(s), a bond between two L.sub.53(s), a bond between L.sub.51 and carbon between X.sub.54 and X.sub.55 in Formula 2, a bond between L.sub.52 and carbon between X.sub.54 and X.sub.56 in Formula 2, and a bond between L.sub.53 and carbon between X.sub.55 and X.sub.56 in Formula 2 may each be a carbon-carbon single bond.

[0297] In Formula 2, X.sub.54 may be N or C(R.sub.54), X.sub.55 may be N or C(R.sub.55), X.sub.56 may be N or C(R.sub.56), and at least one selected from among X.sub.54 to X.sub.56 may be N. R.sub.54 to R.sub.56 may each be the same as described above. In one or more embodiments, two or three selected from among X.sub.54 to X.sub.56 may each be N.

[0298] In Formula 2, R.sub.51 to R.sub.56 may each independently be hydrogen, deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.60 alkyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkenyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkynyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 alkoxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.6-C.sub.60 aryloxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.6-C.sub.60 arylthio group unsubstituted or substituted with at least one R.sub.10a, a C.sub.7-C.sub.60 arylalkyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 heteroarylalkyl group unsubstituted or substituted with at least one R.sub.10a, C(Q.sub.1)(Q.sub.2)(Q.sub.3), Si(Q.sub.1)(Q.sub.2)(Q.sub.3), N(Q.sub.1)(Q.sub.2), B(Q.sub.1)(Q.sub.2), C(O)(Q.sub.1), S(O).sub.2(Q.sub.1), or P(O)(Q.sub.1)(Q.sub.2), and Q.sub.1 to Q.sub.3 may each be the same as described herein.

[0299] In one or more embodiments, in Formula 2, R.sub.51 to R.sub.56 may each independently be: [0300] hydrogen, deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.20 alkyl group, or a C.sub.1-C.sub.20 alkoxy group; [0301] a C.sub.1-C.sub.20 alkyl group or a C.sub.1-C.sub.20 alkoxy group, each substituted with deuterium, F, Cl, Br, I, CD.sub.3, CD.sub.2H, CDH.sub.2, CF.sub.3, CF.sub.2H, CFH.sub.2, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.10 alkyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a naphthyl group, a pyridinyl group, a pyrimidinyl group, or any combination thereof; [0302] a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a (C.sub.1-C.sub.10 alkyl)phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group, a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a benzoisothiazolyl group, a benzoxazolyl group, a benzoisoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, an azacarbazolyl group, an azadibenzofuranyl group, an azadibenzothiophenyl group, an azafluorenyl group, an azadibenzosilolyl group, or a group represented by Formula 91, each unsubstituted or substituted with deuterium, F, Cl, Br, I, CD.sub.3, CD.sub.2H, CDH.sub.2, CF.sub.3, CF.sub.2H, CFH.sub.2, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a (C.sub.1-C.sub.10 alkyl)phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group, a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a benzothiazolyl group, a benzoisoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, O(Q.sub.31), S(Q.sub.31), Si(Q.sub.31)(Q.sub.32)(Q.sub.33), N(Q.sub.31)(Q.sub.32), B(Q.sub.31)(Q.sub.32), P(Q.sub.31)(Q.sub.32), C(O)(Q.sub.31), S(O).sub.2(Q.sub.31), P(O)(Q.sub.31)(Q.sub.32), or any combination thereof; or [0303] C(Q.sub.1)(Q.sub.2)(Q.sub.3), Si(Q.sub.1)(Q.sub.2)(Q.sub.3), N(Q.sub.1)(Q.sub.2), B(Q.sub.1)(Q.sub.2), C(O)(Q.sub.1), S(O).sub.2(Q.sub.1), or P(O)(Q.sub.1)(Q.sub.2), [0304] wherein Q.sub.1 to Q.sub.3 and Q.sub.31 to Q.sub.33 may each independently be: [0305] CH.sub.3, CD.sub.3, CD.sub.2H, CDH.sub.2, CH.sub.2CH.sub.3, CH.sub.2CD.sub.3, CH.sub.2CD.sub.2H, CH.sub.2CDH.sub.2, CHDCH.sub.3, CHDCD.sub.2H, CHDCDH.sub.2, CHDCD.sub.3, CD.sub.2CD.sub.3, CD.sub.2CD.sub.2H, or CD.sub.2CDH.sub.2; or [0306] an n-propyl group, an iso-propyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, an isopentyl group, a sec-pentyl group, a tert-pentyl group, a phenyl group, a naphthyl group, a pyridinyl group, a pyrimidinyl group, a pyridazinyl group, a pyrazinyl group, or a triazinyl group, each unsubstituted or substituted with deuterium, a C.sub.1-C.sub.10 alkyl group, a phenyl group, a biphenyl group, a pyridinyl group, a pyrimidinyl group, a pyridazinyl group, a pyrazinyl group, a triazinyl group, or any combination thereof:

##STR00032## [0307] wherein, in Formula 91, [0308] ring CY.sub.91 and ring CY.sub.92 may each independently be a C.sub.5-C.sub.30 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.30 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, [0309] X.sub.91 may be a single bond, O, S, N(R.sub.91), B(R.sub.91), C(R.sub.91a)(R.sub.91b), or Si(R.sub.91a)(R.sub.91b), [0310] R.sub.91, R.sub.91a, and R.sub.91b may be the same as described with respect to R.sub.82, R.sub.82a, and R.sub.82b, respectively, [0311] R.sub.10a may be the same as described herein, and [0312] * indicates a binding site to a neighboring atom.

[0313] For example, in some embodiments, in Formula 91, [0314] ring CY.sub.91 and ring CY.sub.92 may each independently be a benzene group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, or a triazine group, each unsubstituted or substituted with at least one R.sub.10a, and [0315] R.sub.91, R.sub.91a, and R.sub.91b may each independently be: [0316] hydrogen or a C.sub.1-C.sub.10 alkyl group; or [0317] a phenyl group, a pyridinyl group, a pyrimidinyl group, a pyridazinyl group, a pyrazinyl group, or a triazinyl group, each unsubstituted or substituted with deuterium, a C.sub.1-C.sub.10 alkyl group, a phenyl group, a biphenyl group, a pyridinyl group, a pyrimidinyl group, a pyridazinyl group, a pyrazinyl group, a triazinyl group, or any combination thereof.

[0318] In one or more embodiments, in Formula 2, a group represented by *-(L.sub.51).sub.b51-R.sub.51 and a group represented by *-(L.sub.52).sub.b52-R.sub.52 may each not be a phenyl group.

[0319] In one or more embodiments, a group represented by *-(L.sub.51).sub.b51-R.sub.51 and a group represented by *-(L.sub.52).sub.b52-R.sub.52 in Formula 2 may be identical to each other.

[0320] In one or more embodiments, a group represented by *-(L.sub.51).sub.b51-R.sub.51 and a group represented by *-(L.sub.52).sub.b52-R.sub.52 in Formula 2 may be different from each other.

[0321] In one or more embodiments, in Formula 2, b51 and b52 may each be 1, 2, or 3; and L.sub.51 and L.sub.52 may each independently be a benzene group, a pyridine group, a pyrimidine group, a pyridazine group, a pyrazine group, or a triazine group, each unsubstituted or substituted with at least one R.sub.10a.

[0322] In one or more embodiments, R.sub.51 and R.sub.52 in Formula 2 may each independently be a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.6-C.sub.60 aryloxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.6-C.sub.60 arylthio group unsubstituted or substituted with at least one R.sub.10a, C(Q.sub.1)(Q.sub.2)(Q.sub.3), or Si(Q.sub.1)(Q.sub.2)(Q.sub.3), and [0323] Q.sub.1 to Q.sub.3 may each independently be a C.sub.3-C.sub.60 carbocyclic group or a C.sub.1-C.sub.60 heterocyclic group, each unsubstituted or substituted with deuterium, F, a cyano group, a C.sub.1-C.sub.60 alkyl group, a C.sub.1-C.sub.60 alkoxy group, a phenyl group, a biphenyl group, or any combination thereof.

[0324] In one or more embodiments, [0325] a group represented by *-(L.sub.51).sub.b51-R.sub.51 in Formula 2 may be a group represented by one selected from among Formulae CY51-1 to CY51-26, and/or [0326] a group represented by *-(L.sub.52).sub.b52-R.sub.52 in Formula 2 may be a group represented by one selected from among Formulae CY52-1 to CY52-26, and/or [0327] a group represented by *-(L.sub.53).sub.b53-R.sub.53 in Formula 2 may be a group represented by one selected from among Formulae CY53-1 to CY53-27, C(Q.sub.1)(Q.sub.2)(Q.sub.3), or Si(Q.sub.1)(Q.sub.2)(Q.sub.3):

##STR00033## ##STR00034## ##STR00035## ##STR00036## ##STR00037## ##STR00038## ##STR00039## ##STR00040## ##STR00041## ##STR00042## ##STR00043## ##STR00044## ##STR00045## ##STR00046## [0328] wherein, in Formulae CY51-1 to CY51-26, CY52-1 to CY52-26, and CY53-1 to CY53-27, [0329] Y.sub.63 may be a single bond, O, S, N(R.sub.63), B(R.sub.63), C(R.sub.63a)(R.sub.63b), or Si(R.sub.63a)(R.sub.63b), [0330] Y.sub.64 may be a single bond, O, S, N(R.sub.64), B(R.sub.64), C(R.sub.64a)(R.sub.64b), or Si(R.sub.64a)(R.sub.64b), [0331] Y.sub.67 may be a single bond, O, S, N(R.sub.67), B(R.sub.67), C(R.sub.67a)(R.sub.67b), or Si(R.sub.67a)(R.sub.67b), [0332] Y.sub.68 may be a single bond, O, S, N(R.sub.68), B(R.sub.68), C(R.sub.68a)(R.sub.68b), or Si(R.sub.68a)(R.sub.68b), [0333] Y.sub.63 and Y.sub.64 in Formulae CY51-16 and CY51-17 may not be a single bond at the same time, [0334] Y.sub.67 and Y.sub.68 in Formulae CY52-16 and CY52-17 may not be a single bond at the same time, [0335] R.sub.51a to R.sub.51e, R.sub.61 to R.sub.64, R.sub.63a, R.sub.63b, R.sub.64a, and R.sub.64b may each be the same as described with respect to R.sub.51, wherein R.sub.51a to R.sub.51e may each not be hydrogen, [0336] R.sub.52a to R.sub.52e, R.sub.65 to R.sub.68, R.sub.67a, R.sub.67b, R.sub.68a, and R.sub.68b may each be the same as described with respect to R.sub.52, wherein R.sub.52a to R.sub.52e may each not be hydrogen, [0337] R.sub.53a to R.sub.53e, R.sub.69a, and R.sub.69b may each be the same as described with respect to R.sub.53, wherein R.sub.53a to R.sub.53e may each not be hydrogen, and [0338] * indicates a binding site to a neighboring atom.

[0339] For example, in one or more embodiments, [0340] in Formulae CY51-1 to CY51-26 and CY52-1 to 52-26, R.sub.51a to R.sub.51e and R.sub.52a to R.sub.52e may each independently be: [0341] a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a (C.sub.1-C.sub.10 alkyl)phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group, a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a benzoisothiazolyl group, a benzoxazolyl group, a benzoisoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, an azacarbazolyl group, an azadibenzofuranyl group, an azadibenzothiophenyl group, an azafluorenyl group, an azadibenzosilolyl group, or a group represented by Formula 91, each unsubstituted or substituted with deuterium, F, Cl, Br, I, CD.sub.3, CD.sub.2H, CDH.sub.2, CF.sub.3, CF.sub.2H, CFH.sub.2, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a (C.sub.1-C.sub.10 alkyl)phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group, a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a benzoisothiazolyl group, a benzoxazolyl group, a benzoisoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, or any combination thereof; or [0342] C(Q.sub.1)(Q.sub.2)(Q.sub.3) or Si(Q.sub.1)(Q.sub.2)(Q.sub.3), and [0343] Q.sub.1 to Q.sub.3 may each independently be a phenyl group, a naphthyl group, a pyridinyl group, a pyrimidinyl group, a pyridazinyl group, a pyrazinyl group, or a triazinyl group, each unsubstituted or substituted with deuterium, a C.sub.1-C.sub.10 alkyl group, a phenyl group, a biphenyl group, a pyridinyl group, a pyrimidinyl group, a pyridazinyl group, a pyrazinyl group, a triazinyl group, or any combination thereof, [0344] in Formulae CY51-16 and CY51-17, i) Y.sub.63 may be O or S and Y.sub.64 may be Si(R.sub.64a)(R.sub.64b), or ii) Y.sub.63 may be Si(R.sub.63a)(R.sub.63b) and Y.sub.64 may be O or S, and [0345] in Formulae CY52-16 and CY52-17, i) Y.sub.67 may be O or S, and Y.sub.68 may be Si(R.sub.68a)(R.sub.68b), or ii) Y.sub.67 may be Si(R.sub.67a)(R.sub.67b), and Y.sub.68 may be O or S.

##STR00047##

[0346] In Formula 3, ring CY.sub.71 and ring CY.sub.72 may each independently be a TT electron-rich C.sub.3-C.sub.60 cyclic group or a pyridine group.

[0347] In Formula 3, X.sub.71 may be: a single bond; or a linking group including O, S, N, B, C, Si, or any combination thereof.

[0348] In Formula 3, * indicates a binding site to any atom included in the remaining part other than the group represented by Formula 3 in the third compound.

##STR00048## ##STR00049##

[0349] In Formulae 3-1 to 3-5, ring CY.sub.1 to ring CY.sub.74 may each independently be a electron-rich C.sub.3-C.sub.60 cyclic group or a pyridine group.

[0350] In Formulae 3-1 to 3-5, X.sub.82 may be a single bond, O, S, N-[(L.sub.82).sub.b82-R.sub.82], C(R.sub.82a)(R.sub.82b), or Si(R.sub.82a)(R.sub.82b).

[0351] In Formulae 3-1 to 3-5, X.sub.83 may be a single bond, O, S, N-[(L.sub.83).sub.b83-R.sub.83], C(R.sub.83a)(R.sub.83b), or Si(R.sub.83a)(R.sub.83b).

[0352] In Formulae 3-1 to 3-5, X.sub.84 may be O, S, N-[(L.sub.84).sub.b84-R.sub.84], C(R.sub.84a)(R.sub.84b), or Si(R.sub.84a)(R.sub.84b).

[0353] In Formulae 3-1 to 3-5, X.sub.85 may be C or Si.

[0354] In Formulae 3-1 to 3-5, L.sub.81 to L.sub.85 may each independently be a single bond, *C(Q.sub.4)(Q.sub.5)-*, *Si(Q.sub.4)(Q.sub.5)-*, a electron-rich C.sub.3-C.sub.60 cyclic group unsubstituted or substituted with at least one R.sub.10a, or a pyridine group unsubstituted or substituted with at least one R.sub.10a.

[0355] Q.sub.4 and Q.sub.5 may each be the same as described with respect to Q.sub.1.

[0356] In Formulae 3-1 to 3-5, b81 to b85 may each independently be an integer from 1 to 5.

[0357] In Formulae 3-1 to 3-5, R.sub.71 to R.sub.74, R.sub.81 to R.sub.85, R.sub.82a, R.sub.82b, R.sub.83a, R.sub.83b, R.sub.84a, and R.sub.84b may each be the same as described herein.

[0358] In Formulae 3-1 to 3-5, a71 to a74 indicate the number of R.sub.71(s) to the number of R.sub.74(s), respectively, and may each independently be an integer from 0 to 20. When a71 is 2 or more, two or more R.sub.71(s) may be identical to or different from each other, when a72 is 2 or more, two or more R.sub.72(s) may be identical to or different from each other, when a73 is 2 or more, two or more R.sub.73(s) may be identical to or different from each other, and when a74 is 2 or more, two or more R.sub.74(s) may be identical to or different from each other. In some embodiments, a71 to a74 may each independently be an integer from 0 to 8.

[0359] R.sub.10a may be the same as described herein.

[0360] In Formulae 3-1 to 3-5, L.sub.81 to L.sub.85 may each independently be: [0361] a single bond; or [0362] *C(Q.sub.4)(Q.sub.5)-* or *Si(Q.sub.4)(Q.sub.5)-*; or [0363] a benzene group, a naphthalene group, an anthracene group, a phenanthrene group, a triphenylene group, a pyrene group, a chrysene group, a cyclopentadiene group, a furan group, a thiophene group, a silole group, an indene group, a fluorene group, an indole group, a carbazole group, a benzofuran group, a dibenzofuran group, a benzothiophene group, a dibenzothiophene group, a benzosilole group, a dibenzosilole group, an azafluorene group, an azacarbazole group, an azadibenzofuran group, an azadibenzothiophene group, an azadibenzosilole group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, a quinoline group, an isoquinoline group, a quinoxaline group, a quinazoline group, a phenanthroline group, a pyrrole group, a pyrazole group, an imidazole group, a triazole group, an oxazole group, an isooxazole group, a thiazole group, an isothiazole group, an oxadiazole group, a thiadiazole group, a benzopyrazole group, a benzimidazole group, a benzoxazole group, a benzothiazole group, a benzoxadiazole group, or a benzothiadiazole group, each unsubstituted or substituted with deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a naphthyl group, a pyridinyl group, a pyrimidinyl group, a triazinyl group, a fluorenyl group, a dimethylfluorenyl group, a diphenylfluorenyl group, a carbazolyl group, a phenylcarbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a dibenzosilolyl group, a dimethyldibenzosilolyl group, a diphenyldibenzosilolyl group, O(Q.sub.31), S(Q.sub.31), Si(Q.sub.31)(Q.sub.32)(Q.sub.33), N(Q.sub.31)(Q.sub.32), B(Q.sub.31)(Q.sub.32), P(Q.sub.31)(Q.sub.32), C(O)(Q.sub.31), S(O).sub.2(Q.sub.31), P(O)(Q.sub.31)(Q.sub.32), or any combination thereof, and [0364] Q.sub.4, Q.sub.5, and Q.sub.31 to Q.sub.33 may each independently be hydrogen, deuterium, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a pyridinyl group, a pyrimidinyl group, a pyridazinyl group, a pyrazinyl group, or a triazinyl group.

[0365] In one or more embodiments, a group represented by

##STR00050##

in Formulae 3-1 and 3-2 may be a group represented by one selected from among Formulae CY71-1(1) to CY71-1(8), and/or [0366] a group represented by

##STR00051## in Formulae 3-1 and 3-3 may be a group represented by one selected from among Formulae CY71-2(1) to CY71-2(8), and/or [0367] a group represented by

##STR00052## in Formulae 3-2 and 3-4 may be a group represented by one selected from among Formulae CY71-3(1) to CY71-3(32), [0368] a group represented by

##STR00053## in Formulae 3-3 to 3-5 may be a group represented by one selected from among Formulae CY71-4(1) to CY71-4(32), and/or [0369] a group represented by

##STR00054## in Formula 3-5 may be a group a group represented by represented by one selected from among Formulae CY71-5(1) to CY71-5(8):

##STR00055## ##STR00056## ##STR00057## ##STR00058## ##STR00059## ##STR00060## ##STR00061## ##STR00062## ##STR00063## ##STR00064## ##STR00065## ##STR00066## ##STR00067## ##STR00068## ##STR00069## ##STR00070## ##STR00071## ##STR00072## ##STR00073## ##STR00074## [0370] wherein, in Formulae CY71-1(1) to CY71-1(8), CY71-2(1) to CY71-2(8), CY71-3(1) to CY71-3(32), CY71-4(1) to CY71-4(32), and CY71-5(1) to CY71-5(8), [0371] X.sub.81 to X.sub.85, L.sub.81, b81, R.sub.81, and R.sub.85 may each be the same as described herein, [0372] X.sub.86 may be a single bond, O, S, N(R.sub.86), B(R.sub.86), C(R.sub.86a)(R.sub.86b), or Si(R.sub.86a)(R.sub.86b), [0373] X.sub.87 may be a single bond, O, S, N(R.sub.87), B(R.sub.87), C(R.sub.87a)(R.sub.87b), or Si(R.sub.87a)(R.sub.87b), [0374] in Formulae CY71-1(1) to CY71-1(8) and CY71-4(1) to CY71-4(32), each of X.sub.86 and X.sub.87 may not be a single bond at the same time (e.g., they may not all be a single bond at the same time), [0375] X.sub.88 may be a single bond, O, S, N(R.sub.88), B(R.sub.88), C(R.sub.88a)(R.sub.88b), or Si(R.sub.88a)(R.sub.88b), [0376] X.sub.89 may be a single bond, O, S, N(R.sub.89), B(R.sub.89), C(R.sub.89a)(R.sub.89b), or Si(R.sub.89a)(R.sub.89b), [0377] in Formulae CY71-2(1) to CY71-2(8), CY71-3(1) to CY71-3(32), and CY71-5(1) to CY71-5(8), each of X.sub.88 and X.sub.89 may not be a single bond at the same time (e.g., they may not all be a single bond at the same time), and [0378] R.sub.86 to R.sub.89, R.sub.86a, R.sub.86b, R.sub.87a, R.sub.87b, R.sub.88a, R.sub.88b, R.sub.89a, and R.sub.89b may each be the same as described with respect to R.sub.81.

##STR00075##

[0379] In Formulae 502 and 503, ring A.sub.501 to ring A.sub.504 may each independently be a C.sub.3-C.sub.60 carbocyclic group or a C.sub.1-C.sub.60 heterocyclic group.

[0380] In Formulae 502 and 503, Y.sub.505 may be O, S, N(R.sub.505), B(R.sub.505), C(R.sub.505a)(R.sub.505b), or Si(R.sub.505a)(R.sub.505b).

[0381] In Formulae 502 and 503, Y.sub.506 may be O, S, N(R.sub.506), B(R.sub.506), C(R.sub.506a)(R.sub.506b), or Si(R.sub.506a)(R.sub.506b).

[0382] In Formulae 502 and 503, Y.sub.507 may be O, S, N(R.sub.507), B(R.sub.507), C(R.sub.507a)(R.sub.507b), or Si(R.sub.507a)(R.sub.507b).

[0383] In Formulae 502 and 503, Y.sub.508 may be O, S, N(R.sub.508), B(R.sub.508), C(R.sub.508a)(R.sub.508b), or Si(R.sub.508a)(R.sub.508b).

[0384] In Formulae 502 and 503, Y.sub.51 and Y.sub.52 may each independently be B, P(O), or S(O).

[0385] In Formulae 502 and 503, R.sub.500a, R.sub.500b, R.sub.501 to R.sub.508, R.sub.505a, R.sub.505b, R.sub.506a, R.sub.506b, R.sub.507a, R.sub.507b, R.sub.508a, and R.sub.508b may each be the same as described herein.

[0386] In Formulae 502 and 503, a501 to a504 indicate the number of R.sub.501(s) to the number of R.sub.504(s), respectively, and may each independently be an integer from 0 to 20. When a501 is 2 or more, two or more R.sub.501(s) may be identical to or different from each other, when a502 is 2 or more, two or more R.sub.502(s) may be identical to or different from each other, when a503 is 2 or more, two or more R.sub.503(s) may be identical to or different from each other, and when a504 is 2 or more, two or more R.sub.504(s) may be identical to or different from each other. In some embodiments, a501 to a504 may each independently be an integer from 0 to 8.

[0387] R.sub.51 to R.sub.56, R.sub.71 to R.sub.74, R.sub.81 to R.sub.85, R.sub.82a, R.sub.82b, R.sub.83a, R.sub.83b, R.sub.84a, R.sub.84b, R.sub.500a, R.sub.500b, R.sub.501 to R.sub.508, R.sub.505a, R.sub.505b, R.sub.506a, R.sub.506b, R.sub.507a, R.sub.507b, R.sub.508a, and R.sub.508b in the present disclosure may each independently be hydrogen, deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.60 alkyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkenyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkynyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 alkoxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.6-C.sub.60 aryloxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.6-C.sub.60 arylthio group unsubstituted or substituted with at least one R.sub.10a, a C.sub.7-C.sub.60 arylalkyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 heteroaryl alkyl group unsubstituted or substituted with at least one R.sub.10a, C(Q.sub.1)(Q.sub.2)(Q.sub.3), Si(Q.sub.1)(Q.sub.2)(Q.sub.3), N(Q.sub.1)(Q.sub.2), B(Q.sub.1)(Q.sub.2), C(O)(Q.sub.1), S(O).sub.2(Q.sub.1), or P(O)(Q.sub.1)(Q.sub.2). Q.sub.1 to Q.sub.3 may each be the same as described herein.

[0388] In one or more embodiments, i) R.sub.51 to R.sub.56, R.sub.71 to R.sub.74, R.sub.81 to R.sub.85, R.sub.82a, R.sub.82b, R.sub.83a, R.sub.83b, R.sub.84a, R.sub.84b, R.sub.500a, R.sub.500b, R.sub.501 to R.sub.508, R.sub.505a, R.sub.505b, R.sub.506a, R.sub.506b, R.sub.507a, R.sub.507b, R.sub.508a, and R.sub.508b in Formulae 2, 3-1 to 3-5, 502, and 503 and ii) R.sub.10a may each independently be: [0389] hydrogen, deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.20 alkyl group, or a C.sub.1-C.sub.20 alkoxy group; [0390] a C.sub.1-C.sub.20 alkyl group or a C.sub.1-C.sub.20 alkoxy group, each substituted with deuterium, F, Cl, Br, I, CD.sub.3, CD.sub.2H, CDH.sub.2, CF.sub.3, CF.sub.2H, CFH.sub.2, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.10 alkyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a naphthyl group, a pyridinyl group, a pyrimidinyl group, or any combination thereof; [0391] a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a (C.sub.1-C.sub.10 alkyl)phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group, a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a benzoisothiazolyl group, a benzoxazolyl group, a benzoisoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, an azacarbazolyl group, an azadibenzofuranyl group, an azadibenzothiophenyl group, an azafluorenyl group, an azadibenzosilolyl group, or a group represented by Formula 91, each unsubstituted or substituted with deuterium, F, Cl, Br, I, CD.sub.3, CD.sub.2H, CDH.sub.2, CF.sub.3, CF.sub.2H, CFH.sub.2, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a (C.sub.1-C.sub.10 alkyl)phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group, a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a benzothiazolyl group, a benzoisoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, O(Q.sub.31), S(Q.sub.31), Si(Q.sub.31)(Q.sub.32)(Q.sub.33), N(Q.sub.31)(Q.sub.32), B(Q.sub.31)(Q.sub.32), P(Q.sub.31)(Q.sub.32), C(O)(Q.sub.31), S(O).sub.2(Q.sub.31), P(O)(Q.sub.31)(Q.sub.32), or any combination thereof; or [0392] C(Q.sub.1)(Q.sub.2)(Q.sub.3), Si(Q.sub.1)(Q.sub.2)(Q.sub.3), N(Q.sub.1)(Q.sub.2), B(Q.sub.1)(Q.sub.2), C(O)(Q.sub.1), S(O).sub.2(Q.sub.1), or P(O)(Q.sub.1)(Q.sub.2), [0393] wherein Q.sub.1 to Q.sub.3 and Q.sub.31 to Q.sub.33 may each independently be: [0394] CH.sub.3, CD.sub.3, CD.sub.2H, CDH.sub.2, CH.sub.2CH.sub.3, CH.sub.2CD.sub.3, CH.sub.2CD.sub.2H, CH.sub.2CDH.sub.2, CHDCH.sub.3, CHDCD.sub.2H, CHDCDH.sub.2, CHDCD.sub.3, CD.sub.2CD.sub.3, CD.sub.2CD.sub.2H, or CD.sub.2CDH.sub.2; or [0395] an n-propyl group, an iso-propyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, an isopentyl group, a sec-pentyl group, a tert-pentyl group, a phenyl group, a naphthyl group, a pyridinyl group, a pyrimidinyl group, a pyridazinyl group, a pyrazinyl group, or a triazinyl group, each unsubstituted or substituted with deuterium, a C.sub.1-C.sub.10 alkyl group, a phenyl group, a biphenyl group, a pyridinyl group, a pyrimidinyl group, a pyridazinyl group, a pyrazinyl group, a triazinyl group, or any combination thereof.

[0396] In one or more embodiments, i) R.sub.1 to R.sub.4 in Formula 1 and Z.sub.1 to Z.sub.7 in Formulae 2-1 and 2-2, ii) R.sub.51 to R.sub.56, R.sub.71 to R.sub.74, R.sub.81 to R.sub.85, R.sub.82a, R.sub.82b, R.sub.83a, R.sub.83b, R.sub.84a and R.sub.84b, R.sub.500a, R.sub.500b, R.sub.501 to R.sub.508, R.sub.505a, R.sub.505b, R.sub.506a, R.sub.506b, R.sub.507a, R.sub.507b, R.sub.508a, and R.sub.508b in Formulae 2, 3-1 to 3-5, 502, and 503, and iii) R.sub.10a may each independently be: [0397] hydrogen, deuterium, F, a cyano group, a nitro group, CH.sub.3, CD.sub.3, CD.sub.2H, CDH.sub.2, CF.sub.3, CF.sub.2H, or CFH.sub.2; [0398] a group represented by one selected from among Formulae 9-1 to 9-19; or [0399] a group represented by one selected from among Formulae 10-1 to 10-246, C(Q.sub.1)(Q.sub.2)(Q.sub.3), Si(Q.sub.1)(Q.sub.2)(Q.sub.3), or P(O)(Q.sub.1)(Q.sub.2) (wherein Q.sub.1 to Q.sub.3 may each be the same as described herein):

##STR00076## ##STR00077## ##STR00078## ##STR00079## ##STR00080## ##STR00081## ##STR00082## ##STR00083## ##STR00084## ##STR00085## ##STR00086## ##STR00087## ##STR00088## ##STR00089## ##STR00090## ##STR00091## ##STR00092## ##STR00093## ##STR00094## ##STR00095## ##STR00096## ##STR00097## ##STR00098## ##STR00099## ##STR00100## ##STR00101## ##STR00102## ##STR00103## ##STR00104## ##STR00105## ##STR00106## ##STR00107## ##STR00108## ##STR00109##

##STR00110## [0400] wherein, in Formulae 9-1 to 9-19 and 10-1 to 10-246, * indicates a binding site to a neighboring atom, Ph represents a phenyl group, D represents deuterium, and TMS represents a trimethylsilyl group.

Examples of Compounds

[0401] In one or more embodiments, the organometallic compound represented by Formula 1 may be one selected from among Compounds A-1 to A-21, A-1-D to A-21-D, B-1 to B-21, B-1-D to B-21-D, C-1 to C-21, C-1-D to C-21-D, D-1 to D-21, and D-1-D to D-21-D:

##STR00111## ##STR00112## ##STR00113## ##STR00114## ##STR00115## ##STR00116## ##STR00117## ##STR00118## ##STR00119## ##STR00120## ##STR00121## ##STR00122## ##STR00123## ##STR00124## ##STR00125## ##STR00126## ##STR00127## ##STR00128## ##STR00129## ##STR00130## ##STR00131## ##STR00132## ##STR00133## ##STR00134## ##STR00135## ##STR00136## ##STR00137## ##STR00138##

##STR00139## ##STR00140## ##STR00141## ##STR00142## ##STR00143## ##STR00144## ##STR00145## ##STR00146## ##STR00147## ##STR00148## ##STR00149## ##STR00150## ##STR00151## ##STR00152## ##STR00153## ##STR00154## ##STR00155## ##STR00156## ##STR00157## ##STR00158## ##STR00159## ##STR00160## ##STR00161## ##STR00162## ##STR00163## ##STR00164## ##STR00165## ##STR00166##

[0402] For example, in one or more embodiments, the second compound may be at least one selected from among Compounds ETH1 to ETH100:

##STR00167## ##STR00168## ##STR00169## ##STR00170## ##STR00171## ##STR00172## ##STR00173## ##STR00174## ##STR00175## ##STR00176## ##STR00177## ##STR00178## ##STR00179## ##STR00180## ##STR00181## ##STR00182## ##STR00183## ##STR00184## ##STR00185## ##STR00186## ##STR00187## ##STR00188## ##STR00189## ##STR00190## ##STR00191## ##STR00192## ##STR00193## ##STR00194##

[0403] For example, in one or more embodiments, the third compound may be at least one selected from among Compounds HTH1 to HTH40:

##STR00195## ##STR00196## ##STR00197## ##STR00198## ##STR00199## ##STR00200## ##STR00201## ##STR00202## ##STR00203##

[0404] For example, in one or more embodiments, the fourth compound may be at least one selected from among Compounds DFD1 to DFD29:

##STR00204## ##STR00205## ##STR00206## ##STR00207## ##STR00208## ##STR00209## ##STR00210##

[0405] In the compounds above, Ph represents a phenyl group, D.sub.5 represents substitution with five deuterium, and D.sub.4 represents substitution with four deuterium. For example, a group represented by

##STR00211##

may be identical to a group represented by

##STR00212##

Description of FIG. 1

[0406] FIG. 1 is a schematic cross-sectional view of a light-emitting device 10 according to one or more embodiments of the present disclosure. The light-emitting device 10 may include a first electrode 110, an interlayer 130, and a second electrode 150.

[0407] Hereinafter, the structure of the light-emitting device 10 according to one or more embodiments and a method of manufacturing the light-emitting device 10 will be described with reference to FIG. 1.

First Electrode 110

[0408] In FIG. 1, in one or more embodiments, a substrate may be additionally provided and arranged under the first electrode 110 and/or on the second electrode 150. In one or more embodiments, as the substrate, a glass substrate or a plastic substrate may be utilized. In one or more embodiments, the substrate may be a flexible substrate, and may include plastics with excellent or suitable heat resistance and durability, such as polyimide, polyethylene terephthalate (PET), polycarbonate, polyethylene naphthalate, polyarylate (PAR), polyetherimide, or any combination thereof.

[0409] The first electrode 110 may be formed by, for example, depositing or sputtering a material for forming the first electrode 110 on the substrate. When the first electrode 110 is an anode, a material for forming the first electrode 110 may be a high-work function material that facilitates injection of holes.

[0410] The first electrode 110 may be a reflective electrode, a semi-transmissive electrode, or a transmissive electrode. In one or more embodiments, when the first electrode 110 is a transmissive electrode, a material for forming the first electrode 110 may include indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO.sub.2), zinc oxide (ZnO), or any combination thereof. In one or more embodiments, when the first electrode 110 is a semi-transmissive electrode or a reflective electrode, a material for forming the first electrode 110 may include magnesium (Mg), silver (Ag), aluminum (AI), aluminum-lithium (AlLi), calcium (Ca), magnesium-indium (MgIn), magnesium-silver (MgAg), or any combination thereof.

[0411] The first electrode 110 may have a single-layer structure including (e.g., consisting of) a single layer, or a multi-layer structure including multiple layers. For example, in some embodiments, the first electrode 110 may have a three-layer structure of ITO/Ag/ITO.

Interlayer 130

[0412] The interlayer 130 may be on the first electrode 110. The interlayer 130 may include an emission layer.

[0413] In one or more embodiments, the interlayer 130 may further include a hole transport region between the first electrode 110 and the emission layer and an electron transport region between the emission layer and the second electrode 150.

[0414] In one or more embodiments, the interlayer 130 may further include, in addition to one or more suitable organic materials, a metal-containing compound such as an organometallic compound, an inorganic material such as quantum dots, and/or the like.

[0415] In one or more embodiments, the interlayer 130 may include, i) two or more emitting units sequentially stacked between the first electrode 110 and the second electrode 150, and ii) a charge generation layer between the two or more emitting units. When the interlayer 130 includes the two or more light-emitting units and the charge generation layer, the light-emitting device 10 may be a tandem light-emitting device.

Hole Transport Region in Interlayer 130

[0416] The hole transport region may have: i) a single-layer structure including (e.g., consisting of) a single layer including (e.g., consisting of) a single material, ii) a single-layer structure including (e.g., consisting of) a single layer including (e.g., consisting of) multiple materials that are different from each other, or iii) a multi-layer structure including multiple layers including multiple materials that are different from each other.

[0417] The hole transport region may include a hole injection layer, a hole transport layer, an emission auxiliary layer, an electron blocking layer, or any combination thereof.

[0418] For example, in one or more embodiments, the hole transport region may have a multi-layer structure including a hole injection layer/hole transport layer structure, a hole injection layer/hole transport layer/emission auxiliary layer structure, a hole injection layer/emission auxiliary layer structure, a hole transport layer/emission auxiliary layer structure, or a hole injection layer/hole transport layer/electron-blocking layer structure, wherein constituent layers in each structure are sequentially stacked from the first electrode 110 in each stated order.

[0419] In one or more embodiments, the hole transport region may include a compound represented by Formula 201, a compound represented by Formula 202, or any combination thereof:

##STR00213## [0420] wherein, in Formulae 201 and 202, [0421] L.sub.201 to L.sub.204 may each independently be a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, [0422] L.sub.205 may be *O*, *S*, *N(Q.sub.201)-*, a C.sub.1-C.sub.20 alkylene group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.20 alkenylene group unsubstituted or substituted with at least one R.sub.10a, a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a, or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, [0423] xa1 to xa4 may each independently be an integer from 0 to 5, [0424] xa5 may be an integer from 1 to 10, [0425] R.sub.201 to R.sub.204 and Q.sub.201 may each independently be a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, [0426] R.sub.201 and R.sub.202 may optionally be linked to each other via a single bond, a C.sub.1-C.sub.5 alkylene group unsubstituted or substituted with at least one R.sub.10a, or a C.sub.2-C.sub.5 alkenylene group unsubstituted or substituted with at least one R.sub.10a to form a C.sub.8-C.sub.60 polycyclic group (e.g., a carbazole group and/or the like) unsubstituted or substituted with at least one R.sub.10a (e.g., see Compound HT16), [0427] R.sub.203 and R.sub.204 may optionally be linked to each other via a single bond, a C.sub.1-C.sub.5 alkylene group unsubstituted or substituted with at least one R.sub.10a, or a C.sub.2-C.sub.5 alkenylene group unsubstituted or substituted with at least one R.sub.10a, to form a C.sub.8-C.sub.60 polycyclic group unsubstituted or substituted with at least one R.sub.10a, and [0428] na1 may be an integer from 1 to 4.

[0429] For example, in some embodiments, each of Formulae 201 and 202 may include at least one selected from among groups represented by Formulae CY201 to CY217:

##STR00214## ##STR00215## ##STR00216## ##STR00217## ##STR00218## ##STR00219## ##STR00220## [0430] wherein, in Formulae CY201 to CY217, R.sub.10b and R.sub.10c may each be the same as described with respect to R.sub.10a, ring CY201 to ring CY204 may each independently be a C.sub.3-C.sub.20 carbocyclic group or a C.sub.1-C.sub.20 heterocyclic group, and at least one hydrogen in Formulae CY201 to CY217 may be unsubstituted or substituted with R.sub.10a.

[0431] In one or more embodiments, ring CY201 to ring CY204 in Formulae CY201 to CY217 may each independently be a benzene group, a naphthalene group, a phenanthrene group, or an anthracene group.

[0432] In one or more embodiments, each of Formulae 201 and 202 may include at least one selected from among the groups represented by Formulae CY201 to CY203.

[0433] In one or more embodiments, Formula 201 may include at least one selected from among the groups represented by Formulae CY201 to CY203 and at least one selected from among the groups represented by Formulae CY204 to CY217.

[0434] In one or more embodiments, in Formula 201, xa1 may be 1, R.sub.201 may be one selected from among the groups represented by Formulae CY201 to CY203, xa2 may be 0, and R.sub.202 may be one selected from among the groups represented by Formulae CY204 to CY207.

[0435] In one or more embodiments, each of Formulae 201 and 202 may not include (e.g., may exclude) any group represented by Formulae CY201 to CY203.

[0436] In one or more embodiments, each of Formulae 201 and 202 may not include (e.g., may exclude) any group represented by Formulae CY201 to CY203, and may include at least one selected from among the groups represented by Formulae CY204 to CY217.

[0437] In one or more embodiments, each of Formulae 201 and 202 may not include (e.g., may exclude) any group represented by Formulae CY201 to CY217. For example, in one or more embodiments, the hole transport region may include: at least one selected from among Compounds HT1 to HT46; 4,4,4-[tris(3-methylphenyl)phenylamino] triphenylamine (m-MTDATA); 4,4,4-tris(N,N-diphenylamino) triphenylamine (TDATA); 4,4,4-tris[N-(2-naphthyl)-N-phenylamino]-triphenylamine (2-TNATA); N,N-di(naphthalen-1-yl)-N, N-diphenyl-benzidine (NPB(NPD)); -NPB; N,N-bis(3-methylphenyl)-N,N-diphenyl-[1,1-biphenyl]-4,4-diamine (TPD); spiro-TPD; spiro-NPB; methylated NPB; 4,4-cyclohexylidene bis[N,N-bis(4-methylphenyl)benzenamine] (TAPC); 4,4-bis[N,N-(3-tolyl)amino]-3,3-dimethylbiphenyl (HMTPD); 4,4,4-tris(N-carbazolyl)triphenylamine (TCTA); polyaniline/dodecylbenzenesulfonic acid (PANI/DBSA); poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS); polyaniline/camphor sulfonic acid (PANI/CSA); polyaniline/poly(4-styrenesulfonate) (PANI/PSS); or any combination thereof:

##STR00221## ##STR00222## ##STR00223## ##STR00224## ##STR00225## ##STR00226## ##STR00227## ##STR00228## ##STR00229## ##STR00230## ##STR00231## ##STR00232## ##STR00233## ##STR00234## ##STR00235## ##STR00236## ##STR00237##

[0438] A thickness of the hole transport region may be in a range of about 50 to about 10,000 , for example, about 100 to about 4,000 . When the hole transport region includes a hole injection layer, a hole transport layer, or any combination thereof, a thickness of the hole injection layer may be in a range of about 100 to about 9,000 , for example, about 100 to about 1,000 , and a thickness of the hole transport layer may be in a range of about 50 to about 2,000 , for example, about 100 to about 1,500 . When the thicknesses of the hole transport region, the hole injection layer, and the hole transport layer are within these ranges, satisfactory hole transporting characteristics may be obtained without a substantial increase in driving voltage.

[0439] The emission auxiliary layer may increase light-emission efficiency by compensating for an optical resonance distance according to the wavelength of light emitted by the emission layer, and the electron-blocking layer may block or reduce the leakage of electrons from the emission layer to the hole transport region. Materials that may be included in the hole transport region may be included in the emission auxiliary layer and the electron blocking layer.

p-Dopant

[0440] In one or more embodiments, the hole transport region may further include, in addition to the aforementioned materials, a charge-generation material for the improvement of conductive properties. The charge-generation material may be substantially uniformly or non-uniformly dispersed in the hole transport region (e.g., in the form of a single layer including (e.g., consisting of) a charge-generation material).

[0441] The charge-generation material may be, for example, a p-dopant.

[0442] For example, in some embodiments, the p-dopant may have a LUMO energy level of less than or equal to 3.5 eV.

[0443] In one or more embodiments, the p-dopant may include a quinone derivative, a cyano group-containing compound, a compound including element EL1 and element EL2, or any combination thereof.

[0444] Non-limiting examples of the quinone derivative may include tetracyanoquinodimethane (TCNQ), 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ), and/or the like.

[0445] Non-limiting examples of the cyano group-containing compound may include dipyrazino[2,3-f: 2,3-h] quinoxaline-2,3,6,7,10,11-hexacarbonitrile (HAT-CN), a compound represented by Formula 221, and/or the like:

##STR00238## [0446] wherein, in Formula 221, [0447] R.sub.221 to R.sub.223 may each independently be a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group that is unsubstituted or substituted with at least one R.sub.10a, and [0448] at least one selected from among R.sub.221 to R.sub.223 may each independently be a C.sub.3-C.sub.60 carbocyclic group or a C.sub.1-C.sub.60 heterocyclic group, each substituted with: a cyano group; F; Cl; Br; I; a C.sub.1-C.sub.20 alkyl group substituted with a cyano group, F, Cl, Br, I, or any combination thereof; or any combination thereof.

[0449] In the compound including element EL1 and element EL2, element EL1 may be metal, metalloid, or any combination thereof, and element EL2 may be non-metal, metalloid, or any combination thereof.

[0450] Non-limiting examples of the metal may include: an alkali metal (e.g., lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), etc.); an alkaline earth metal (e.g., beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), etc.); a transition metal (e.g., titanium (Ti), zirconium (Zr), hafnium (Hf), vanadium (V), niobium (Nb), tantalum (Ta), chromium (Cr), molybdenum (Mo), tungsten (W), manganese (Mn), technetium (Tc), rhenium (Re), iron (Fe), ruthenium (Ru), osmium (Os), cobalt (Co), rhodium (Rh), iridium (Ir), nickel (Ni), palladium (Pd), platinum (Pt), copper (Cu), silver (Ag), gold (Au), etc.); a post-transition metal (e.g., zinc (Zn), indium (In), tin (Sn), etc.); a lanthanide metal (e.g., lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), etc.); and/or the like.

[0451] Non-limiting examples of the metalloid may include silicon (Si), antimony (Sb), tellurium (Te), and/or the like.

[0452] Non-limiting examples of the non-metal may include oxygen (O), a halogen (e.g., F, Cl, Br, I, etc.), and/or the like.

[0453] For example, in one or more embodiments, the compound containing element EL1 and element EL2 may include metal oxides, metal halides (e.g., metal fluorides, metal chlorides, metal bromides, metal iodides, etc.), metalloid halides (e.g., metalloid fluorides, metalloid chlorides, metalloid bromides, metalloid iodides, etc.), metal tellurides, or any combination thereof.

[0454] Non-limiting examples of the metal oxide may include tungsten oxides (e.g., WO, W.sub.2O.sub.3, WO.sub.2, WO.sub.3, W.sub.2O.sub.5, etc.), vanadium oxides (e.g., VO, V.sub.2O.sub.3, VO.sub.2, V.sub.2O.sub.5, etc.), molybdenum oxides (e.g., MoO, Mo.sub.2O.sub.3, MoO.sub.2, MoO.sub.3, Mo.sub.2O.sub.5, etc.), rhenium oxides (e.g., ReO.sub.3, etc.), and/or the like.

[0455] Non-limiting examples of the metal halide may include alkali metal halides, alkaline earth metal halides, transition metal halides, post-transition metal halides, lanthanide metal halides, and/or the like.

[0456] Non-limiting examples of the alkali metal halide may include LiF, NaF, KF, RbF, CsF, LiCl, NaCl, KCl, RbCl, CsCl, LiBr, NaBr, KBr, RbBr, CsBr, LiI, NaI, KI, RbI, CsI, and/or the like.

[0457] Non-limiting examples of the alkaline earth metal halide may include BeF.sub.2, MgF.sub.2, CaF.sub.2, SrF.sub.2, BaF.sub.2, BeCl.sub.2, MgCl.sub.2, CaCl.sub.2), SrCl.sub.2, BaCl.sub.2, BeBr.sub.2, MgBr.sub.2, CaBr.sub.2, SrBr.sub.2, BaBr.sub.2, BeI.sub.2, MgI.sub.2, CaI.sub.2, SrI.sub.2, BaI.sub.2, and/or the like.

[0458] Non-limiting examples of the transition metal halide may include titanium halides (e.g., TiF.sub.4, TiCl.sub.4, TiBr.sub.4, TiI.sub.4, etc.), zirconium halides (e.g., ZrF.sub.4, ZrCl.sub.4, ZrBr.sub.4, ZrI.sub.4, etc.), hafnium halides (e.g., HfF.sub.4, HfCl.sub.4, HfBr.sub.4, HfI.sub.4, etc.), vanadium halides (e.g., VF.sub.3, VCl.sub.3, VBr.sub.3, VI.sub.3, etc.), niobium halides (e.g., NbF.sub.3, NbCl.sub.3, NbBr.sub.3, NbI.sub.3, etc.), tantalum halides (e.g., TaF.sub.3, TaCl.sub.3, TaBr.sub.3, TaI.sub.3, etc.), chromium halides (e.g., CrF.sub.3, CrCl.sub.3, CrBr.sub.3, CrI.sub.3, etc.), molybdenum halides (e.g., MoF.sub.3, MoCl.sub.3, MoBr.sub.3, MoI.sub.3, etc.), tungsten halides (e.g., WF.sub.3, WCl.sub.3, WBr.sub.3, WI.sub.3, etc.), manganese halides (e.g., MnF.sub.2, MnCl.sub.2, MnBr.sub.2, MnI.sub.2, etc.), technetium halides (e.g., TcF.sub.2, TcCl.sub.2, TcBr.sub.2, TcI.sub.2, etc.), rhenium halides (e.g., ReF.sub.2, ReCl.sub.2, ReBr.sub.2, ReI.sub.2, etc.), ferrous halides (e.g., FeF.sub.2, FeCl.sub.2, FeBr.sub.2, FeI.sub.2, etc.), ruthenium halides (e.g., RuF.sub.2, RuCl.sub.2, RuBr.sub.2, RuI.sub.2, etc.), osmium halides (e.g., OsF.sub.2, OsCl.sub.2, OsBr.sub.2, OsI.sub.2, etc.), cobalt halides (e.g., CoF.sub.2, CoCl.sub.2, CoBr.sub.2, CoI.sub.2, etc.), rhodium halides (e.g., RhF.sub.2, RhCl.sub.2, RhBr.sub.2, RhI.sub.2, etc.), iridium halides (e.g., IrF.sub.2, IrCl.sub.2, IrBr.sub.2, IrI.sub.2, etc.), nickel halides (e.g., NiF.sub.2, NiCl.sub.2, NiBr.sub.2, NiI.sub.2, etc.), palladium halides (e.g., PdF.sub.2, PdCl.sub.2, PdBr.sub.2, PdI.sub.2, etc.), platinum halides (e.g., PtF.sub.2, PtCl.sub.2, PtBr.sub.2, PtI.sub.2, etc.), cuprous halides (e.g., CuF, CuCl, CuBr, CuI, etc.), silver halides (e.g., AgF, AgCl, AgBr, AgI, etc.), gold halides (e.g., AuF, AuCl, AuBr, AuI, etc.), and/or the like.

[0459] Non-limiting examples of the post-transition metal halide may include zinc halides (e.g., ZnF.sub.2, ZnCl.sub.2, ZnBr.sub.2, ZnI.sub.2, etc.), indium halides (e.g., InI.sub.3, etc.), tin halides (e.g., SnI.sub.2, etc.), and/or the like.

[0460] Non-limiting examples of the lanthanide metal halide may include YbF, YbF.sub.2, YbF.sub.3, SmF.sub.3, YbCl, YbCl.sub.2, YbCl.sub.3, SmCl.sub.3, YbBr, YbBr.sub.2, YbBr.sub.3, SmBr.sub.3, YbI, YbI.sub.2, YbI.sub.3, SmI.sub.3, and/or the like.

[0461] Non-limiting examples of the metalloid halide may include antimony halide (e.g., SbCl.sub.5, etc.) and/or the like.

[0462] Non-limiting examples of the metal telluride may include alkali metal tellurides (for example, Li.sub.2Te, Na.sub.2Te, K.sub.2Te, Rb.sub.2Te, Cs.sub.2Te, etc.), alkaline earth metal tellurides (for example, BeTe, MgTe, CaTe, SrTe, BaTe, etc.), transition metal tellurides (for example, TiTe.sub.2, ZrTe.sub.2, HfTe.sub.2, V.sub.2Te.sub.3, Nb.sub.2Te.sub.3, Ta.sub.2Te.sub.3, Cr.sub.2Te.sub.3, Mo.sub.2Te.sub.3, W.sub.2Te.sub.3, MnTe, TcTe, ReTe, FeTe, RuTe, OsTe, CoTe, RhTe, IrTe, NiTe, PdTe, PtTe, Cu.sub.2Te, CuTe, Ag.sub.2Te, AgTe, Au.sub.2Te, etc.), post-transition metal tellurides (for example, ZnTe, etc.), lanthanide metal tellurides (for example, LaTe, CeTe, PrTe, NdTe, PmTe, EuTe, GdTe, TbTe, DyTe, HoTe, ErTe, TmTe, YbTe, LuTe, etc.), and/or the like.

Emission Layer in Interlayer 130

[0463] When the light-emitting device 10 is a full-color light-emitting device, the emission layer may be patterned into a red emission layer, a green emission layer, and/or a blue emission layer, according to a sub-pixel. In one or more embodiments, the emission layer may have a stacked structure of two or more layers selected from among a red emission layer, a green emission layer, and a blue emission layer, in which the two or more layers contact each other or are separated from each other, to emit white light (e.g., combined white light). In one or more embodiments, the emission layer may include two or more materials selected from among a red light-emitting material, a green light-emitting material, and a blue light-emitting material, in which the two or more materials are mixed with each other in a single layer, to emit white light (e.g., combined white light).

[0464] In one or more embodiments, the emission layer may include a host and a dopant (or emitter). In one or more embodiments, the emission layer may further include an auxiliary dopant that promotes energy transfer to the dopant (or emitter), in addition to the host and the dopant (or emitter). When the emission layer includes the dopant (or emitter) and the auxiliary dopant, the dopant (or emitter) and the auxiliary dopant are different from each other.

[0465] The organometallic compound represented by Formula 1 in the present disclosure may serve as the dopant (or emitter), or may serve as the auxiliary dopant.

[0466] An amount (weight) of the dopant (or emitter) in the emission layer may be in a range of about 0.01 parts by weight to about 15 parts by weight based on 100 parts by weight of the host.

[0467] In one or more embodiments, the emission layer may include the organometallic compound represented by Formula 1. An amount of the organometallic compound in the emission layer may be, based on 100 parts by weight of the emission layer, in a range of about 0.01 parts by weight to about 30 parts by weight, about 0.1 parts by weight to about 20 parts by weight, or about 0.1 parts by weight to about 15 parts by weight.

[0468] In one or more embodiments, the emission layer may include a quantum dot.

[0469] In one or more embodiments, the emission layer may include a delayed fluorescence material. The delayed fluorescence material may act as a host or a dopant in the emission layer.

[0470] A thickness of the emission layer may be in a range of about 100 to about 1,000 , for example, about 200 to about 600 . When the thickness of the emission layer is within these ranges, excellent or suitable luminescence characteristics may be obtained without a substantial increase in driving voltage.

Host

[0471] In one or more embodiments, the host in the emission layer may include the second compound, the third compound described in the present disclosure, or any combination thereof.

[0472] In one or more embodiments, the host may include a compound represented by Formula 301:

[Ar.sub.301].sub.xb11-[(L.sub.301).sub.xb1-R.sub.301].sub.xb21,Formula 301 [0473] wherein, in Formula 301, [0474] Ar.sub.301 and L.sub.301 may each independently be a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group that is unsubstituted or substituted with at least one R.sub.10a, [0475] xb11 may be 1, 2, or 3, [0476] xb1 may be an integer from 0 to 5, [0477] R.sub.301 may be hydrogen, deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.60 alkyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkenyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkynyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 alkoxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, Si(Q.sub.301)(Q.sub.302)(Q.sub.303), N(Q.sub.301)(Q.sub.302), B(Q.sub.301)(Q.sub.302), C(O)(Q.sub.301), S(O).sub.2(Q.sub.301), or P(O)(Q.sub.301)(Q.sub.302), [0478] xb21 may be an integer from 1 to 5, and [0479] Q.sub.301 to Q.sub.303 may each be the same as described with respect to Q.sub.1.

[0480] For example, in some embodiments, when xb11 in Formula 301 is 2 or more, two or more Ar.sub.301(s) may be linked to each other via a single bond.

[0481] In one or more embodiments, the host may include a compound represented by Formula 301-1, a compound represented by Formula 301-2, or any combination thereof:

##STR00239## [0482] wherein, in Formulae 301-1 and 301-2, [0483] ring A.sub.301 to ring A.sub.304 may each independently be a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, [0484] X.sub.301 may be O, S, N-[(L.sub.304).sub.xb4-R.sub.304], C(R.sub.304)(R.sub.305), or Si(R.sub.304)(R.sub.305), [0485] xb22 and xb23 may each independently be 0, 1, or 2, [0486] L.sub.301, xb1, and R.sub.301 may each be the same as described herein, [0487] L.sub.302 to L.sub.304 may each independently be the same as described with respect to L.sub.301, [0488] xb2 to xb4 may each independently be the same as described with respect to xb1, and [0489] R.sub.302 to R.sub.305 and R.sub.311 to R.sub.314 may each be the same as described herein with respect to R.sub.301.

[0490] In one or more embodiments, the host may include an alkaline earth metal complex, a post-transition metal complex, or any combination thereof. In one or more embodiments, the host may include a Be complex (for example, Compound H55), an Mg complex, a Zn complex, or any combination thereof.

[0491] In one or more embodiments, the host may include: at least one selected from among Compounds H1 to H128; 9,10-di(2-naphthyl) anthracene (ADN); 2-methyl-9,10-bis(naphthalen-2-yl)anthracene (MADN); 9,10-di(2-naphthyl)-2-t-butyl-anthracene (TBADN); 4,4-bis(N-carbazolyl)-1,1-biphenyl (CBP); 1,3-di(carbazol-9-yl)benzene (mCP); 1,3,5-tri(carbazol-9-yl)benzene (TCP); or any combination thereof:

##STR00240## ##STR00241## ##STR00242## ##STR00243## ##STR00244## ##STR00245## ##STR00246## ##STR00247## ##STR00248## ##STR00249## ##STR00250## ##STR00251## ##STR00252## ##STR00253## ##STR00254## ##STR00255## ##STR00256## ##STR00257## ##STR00258## ##STR00259## ##STR00260## ##STR00261## ##STR00262## ##STR00263## ##STR00264## ##STR00265## ##STR00266## ##STR00267##

##STR00268## ##STR00269## ##STR00270##

[0492] In one or more embodiments, the host may include a silicon-containing compound, a phosphine oxide-containing compound, or any combination thereof.

[0493] The host may have one or more suitable modifications. For example, the host may include only one kind of compound, or may include two or more kinds of different compounds.

Phosphorescent Dopant

[0494] The emission layer may include, as a phosphorescent dopant, the organometallic compound represented by Formula 1 as described in the present disclosure.

[0495] In one or more embodiments, when the emission layer includes the organometallic compound represented by Formula 1 and the organometallic compound represented by Formula 1 serves as an auxiliary dopant, the emission layer may include a phosphorescent dopant.

[0496] The phosphorescent dopant may include at least one transition metal as a central metal.

[0497] The phosphorescent dopant may include a monodentate ligand, a bidentate ligand, a tridentate ligand, a tetradentate ligand, a pentadentate ligand, a hexadentate ligand, or any combination thereof.

[0498] The phosphorescent dopant may be electrically neutral.

[0499] For example, in some embodiments, the phosphorescent dopant may include an organometallic compound represented by Formula 401:

M(L.sub.401).sub.xc1(L.sub.402).sub.xc2Formula 401

##STR00271## [0500] wherein, in Formulae 401 and 402, [0501] M may be a transition metal (e.g., iridium (Ir), platinum (Pt), palladium (Pd), osmium (Os), titanium (Ti), gold (Au), hafnium (Hf), europium (Eu), terbium (Tb), rhodium (Rh), rhenium (Re), or thulium (Tm)), [0502] L.sub.401 may be a ligand represented by Formula 402, and xc1 may be 1, 2, or 3, wherein, when xc1 is 2 or more, two or more L.sub.401(s) may be identical to or different from each other, [0503] L.sub.402 may be an organic ligand, and xc2 may be 0, 1, 2, 3, or 4, and when xc2 is 2 or more, two or more L.sub.402(s) may be identical to or different from each other, [0504] X.sub.401 and X.sub.402 may each independently be N or C, [0505] ring A.sub.401 and ring A.sub.402 may each independently be a C.sub.3-C.sub.60 carbocyclic group or a C.sub.1-C.sub.60 heterocyclic group, [0506] T.sub.401 may be a single bond, *O*, *S*, *C(O)*, *N(Q.sub.411)-*, *C(Q.sub.411)(Q.sub.412)-*, *C(Q.sub.411)C(Q.sub.412)-*, *C(Q.sub.411)=*, or *C(Q.sub.411)-*, [0507] X.sub.403 and X.sub.404 may each independently be a chemical bond (e.g., a covalent bond or a coordinate bond), O, S, N(Q.sub.413), B(Q.sub.413), P(Q.sub.413), C(Q.sub.413)(Q.sub.414), or Si(Q.sub.413)(Q.sub.414), [0508] Q.sub.411 to Q.sub.414 may each be the same as described with respect to Q.sub.1, [0509] R.sub.401 and R.sub.402 may each independently be hydrogen, deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.20 alkyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.20 alkoxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.5-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, Si(Q.sub.401)(Q.sub.402)(Q.sub.403), N(Q.sub.401)(Q.sub.402), B(Q.sub.401)(Q.sub.402), C(O)(Q.sub.401), S(O).sub.2(Q.sub.401), or P(O)(Q.sub.401)(Q.sub.402), [0510] Q.sub.401 to Q.sub.403 may each be the same as described with respect to Q.sub.1, [0511] xc11 and xc12 may each independently be an integer from 0 to 10, and [0512] * and * in Formula 402 each indicate a binding site to M in Formula 401.

[0513] For example, in some embodiments, in Formula 402, i) X.sub.401 may be nitrogen and X.sub.402 may be carbon, or ii) each of X.sub.401 and X.sub.402 may be nitrogen.

[0514] In one or more embodiments, when xc1 in Formula 401 is 2 or more, two ring A.sub.401(s) among two or more L.sub.401(s) may optionally be linked to each other via T.sub.402, which is a linking group, and/or two ring A.sub.402(s) among two or more L.sub.401(s) may optionally be linked to each other via T.sub.403, which is a linking group (see Compounds PD1 to PD4 and PD7). T.sub.402 and T.sub.403 may each be the same as described with respect to T.sub.401.

[0515] In Formula 401, L.sub.402 may be an organic ligand. For example, L.sub.402 may include a halogen, a diketone group (e.g., an acetylacetonate group), a carboxylic acid group (e.g., a picolinate group), C(O), an isonitrile group, CN group, a phosphorus-containing group (e.g., a phosphine group, a phosphite group, etc.), or any combination thereof.

[0516] In one or more embodiments, the phosphorescent dopant may include, for example, one selected from among Compounds PD1 to PD39, or any combination thereof:

##STR00272## ##STR00273## ##STR00274## ##STR00275## ##STR00276## ##STR00277## ##STR00278## ##STR00279## ##STR00280##

Fluorescent Dopant

[0517] In one or more embodiments, when the emission layer includes the organometallic compound represented by Formula 1 and the organometallic compound represented by Formula 1 serves as an auxiliary dopant, the emission layer may further include a fluorescent dopant.

[0518] In one or more embodiments, when the emission layer includes the organometallic compound represented by Formula 1 and the organometallic compound represented by Formula 1 serves as a phosphorescent dopant, the emission layer may further include an auxiliary dopant.

[0519] The fluorescent dopant and the auxiliary dopant may each independently include an arylamine compound, a styrylamine compound, a boron-containing compound, or any combination thereof.

[0520] In one or more embodiments, the fluorescent dopant and the auxiliary dopant may each independently include a compound represented by Formula 501:

##STR00281## [0521] wherein, in Formula 501, [0522] Ar.sub.501, L.sub.501 to L.sub.503, R.sub.501, and R.sub.502 may each independently be a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, [0523] xd1 to xd3 may each independently be 0, 1, 2, or 3, and [0524] xd4 may be 1, 2, 3, 4, 5, or 6.

[0525] For example, in some embodiments, Ar.sub.501 in Formula 501 may be a condensed cyclic group (e.g., an anthracene group, a chrysene group, a pyrene group, etc.) in which three or more monocyclic groups are condensed together.

[0526] For example, in some embodiments, xd4 in Formula 501 may be 2.

[0527] For example, in one or more embodiments, the fluorescent dopant and the auxiliary dopant may each include at least one selected from among Compounds FD1 to FD37, 4,4-bis(2,2-diphenylvinyl)-1,1-biphenyl (DPVBi), 4,4-bis[4-(N,N-diphenylamino)styryl]biphenyl (DPAVBi), or any combination thereof:

##STR00282## ##STR00283## ##STR00284## ##STR00285## ##STR00286## ##STR00287##

Delayed Fluorescence Material

[0528] In one or more embodiments, the emission layer may include a delayed fluorescence material.

[0529] In the present disclosure, the delayed fluorescence material may be selected from compounds capable of emitting delayed fluorescence based on a delayed fluorescence emission mechanism.

[0530] The delayed fluorescence material may include, for example, the fourth compound described herein.

[0531] The delayed fluorescence material included in the emission layer may act as a host or a dopant depending on the type or kind of other materials included in the emission layer.

[0532] In one or more embodiments, a difference between a triplet energy level (eV) of the delayed fluorescence material and a singlet energy level (eV) of the delayed fluorescence material may be about 0 eV or more and about 0.5 eV or less. When the difference between the triplet energy level of the delayed fluorescence material and the singlet energy level of the delayed fluorescence material is satisfied with the ranges above, up-conversion from the triplet state to the singlet state of the delayed fluorescence materials may effectively occur, and thus, the luminescence efficiency and/or the like of the light-emitting device 10 may be improved.

[0533] For example, in one or more embodiments, the delayed fluorescence material may include i) a material including at least one electron donor (e.g., a electron-rich C.sub.3-C.sub.60 cyclic group, such as a carbazole group, etc.) and at least one electron acceptor (e.g., a sulfoxide group, a cyano group, a Ir electron-deficient nitrogen-containing C.sub.1-C.sub.60 heterocyclic group, etc.), and/or ii) a material including a C.sub.8-C.sub.60 polycyclic group in which two or more cyclic groups are condensed while sharing boron (B).

[0534] Non-limiting examples of the delayed fluorescence material may include at least one selected from among Compounds DF1 to DF14:

##STR00288## ##STR00289## ##STR00290## ##STR00291##

Quantum Dot

[0535] In one or more embodiments, the emission layer may include one or more quantum dots.

[0536] The term quantum dot as utilized herein refers to a crystal of a semiconductor compound, and may include any material capable of emitting light of one or more suitable emission wavelengths according to the size of the crystal.

[0537] A diameter of the quantum dots may be, for example, in a range of about 1 nm to about 10 nm. In the present disclosure, when dot, dots, or dot particles are spherical, diameter indicates a particle diameter or an average particle diameter, and when the particles are non-spherical, the diameter indicates a major axis length or an average major axis length. The diameter of the particles may be measured utilizing a scanning electron microscope or a particle size analyzer. As the particle size analyzer, for example, HORIBA, LA-950 laser particle size analyzer, may be utilized. When the size of the particles is measured utilizing a particle size analyzer, the average particle diameter is referred to as D50. D50 refers to the average diameter of particles whose cumulative volume corresponds to 50 vol % in the particle size distribution (e.g., cumulative distribution), and refers to the value of the particle size corresponding to 50% from the smallest particle when the total number of particles is 100% in the distribution curve accumulated in the order of the smallest particle size to the largest particle size.

[0538] The quantum dots may be synthesized by a wet chemical process, a metal organic chemical vapor deposition process, a molecular beam epitaxy process, or any process similar thereto.

[0539] The wet chemical process is a method including mixing a precursor material of a quantum dot with an organic solvent and then growing quantum dot particle crystals. When the crystals grow, the organic solvent naturally acts as a dispersant coordinated on the surface of the quantum dot crystals and controls the growth of the crystals so that the growth of quantum dot particles may be controlled or selected through a process which costs lower and is easier than vapor deposition methods, such as metal organic chemical vapor deposition (MOCVD) or molecular beam epitaxy (MBE).

[0540] The quantum dots may include: a Group II-VI semiconductor compound; a Group III-V semiconductor compound; a Group III-VI semiconductor compound; a Group I-III-VI semiconductor compound; a Group IV-VI semiconductor compound; a Group IV element or compound; or any combination thereof.

[0541] Non-limiting examples of the Group II-VI semiconductor compound may include: a binary compound, such as CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, MgSe, MgS, etc.; a ternary compound, such as CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, MgZnSe, MgZnS, etc.; a quaternary compound, such as CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, HgZnSTe, etc.; or any combination thereof.

[0542] Non-limiting examples of the Group III-V semiconductor compound may include: a binary compound, such as GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, etc.; a ternary compound, such as GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InGaP, InNP, InAlP, InNAs, InNSb, InPAs, InPSb, etc.; a quaternary compound, such as GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, InAlPSb, etc.; or any combination thereof. In some embodiments, the Group III-V semiconductor compound may further include a Group II element. Non-limiting examples of the Group III-V semiconductor compound further including a Group II element may include InZnP, InGaZnP, InAlZnP, etc.

[0543] Non-limiting examples of the Group III-VI semiconductor compound may include: a binary compound, such as GaS, GaSe, Ga.sub.2Se.sub.3, GaTe, InS, InSe, In.sub.2S.sub.3, In.sub.2Se.sub.3, InTe, etc.; a ternary compound, such as InGaS.sub.3, InGaSe.sub.3, etc.; or any combination thereof.

[0544] Non-limiting examples of the Group I-III-VI semiconductor compound may include: a ternary compound, such as AgInS, AgInS.sub.2, CuInS, CuInS.sub.2, CuGaO.sub.2, AgGaO.sub.2, AgAlO.sub.2, etc.; or any combination thereof.

[0545] Non-limiting examples of the Group IV-VI semiconductor compound may include: a binary compound, such as SnS, SnSe, SnTe, PbS, PbSe, or PbTe; a ternary compound, such as SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, etc.; a quaternary compound, such as SnPbSSe, SnPbSeTe, SnPbSTe, etc.; or any combination thereof.

[0546] The Group IV element or compound may include: a single element compound, such as Si, Ge, etc.; a binary compound, such as SiC, SiGe, etc.; or any combination thereof.

[0547] Each element included in a multi-element compound, such as the binary compound, the ternary compound, and the quaternary compound, may be present at a substantially uniform concentration or non-substantially uniform concentration in a particle.

[0548] In some embodiments, the quantum dots may have a single structure in which the concentration of each element in the quantum dots is substantially uniform, or a core-shell dual structure. For example, in some embodiments, materials included in the core and materials included in the shell may be different from each other.

[0549] The shell of the quantum dots (e.g., the shell of (e.g., the shell around the core of) each of the quantum dots) may act as a protective layer that prevents chemical degeneration of the core to maintain semiconductor characteristics, and/or as a charging layer that imparts electrophoretic characteristics to the quantum dots. The shell may be single-layered or multi-layered. The interface between the core and the shell may have a concentration gradient in which the concentration of an element existing in the shell decreases toward the center of the core.

[0550] Non-limiting examples of the shell of the quantum dots may include: oxides of metal, metalloid, or non-metal, semiconductor compounds; or any combination thereof. Non-limiting examples of the oxide of metal, metalloid, or non-metal may include: a binary compound, such as SiO.sub.2, Al.sub.2O.sub.3, TiO.sub.2, ZnO, MnO, Mn.sub.2O.sub.3, Mn.sub.3O.sub.4, CuO, FeO, Fe.sub.2O.sub.3, Fe.sub.3O.sub.4, CoO, Co.sub.3O.sub.4, NiO, etc.; a ternary compound, such as MgAl.sub.2O.sub.4, CoFe.sub.2O.sub.4, NiFe.sub.2O.sub.4, CoMn.sub.2O.sub.4, etc.; and any combination thereof. Non-limiting examples of the semiconductor compound may include: as described above, a Group II-VI semiconductor compound; a Group III-V semiconductor compound; a Group III-VI semiconductor compound; a Group I-III-VI semiconductor compound; a Group IV-VI semiconductor compound; or any combination thereof. Non-limiting examples of the semiconductor compound suitable as a shell may include CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnSeS, ZnTeS, GaAs, GaP, GaSb, HgS, HgSe, HgTe, InAs, InP, InGaP, InSb, AlAs, AlP, AlSb, or any combination thereof.

[0551] A full width at half maximum (FWHM) of an emission spectrum of the quantum dots may be about 45 nm or less, for example, about 40 nm or less, or for example, about 30 nm or less, and within these ranges, color purity or color reproducibility of the quantum dots may be improved. In some embodiments, because light emitted through the quantum dots is emitted in all directions, the wide viewing angle may be improved.

[0552] In some embodiments, the quantum dots may be in the form of a spherical particle, a pyramidal particle, a multi-arm particle, a cubic nanoparticle, a nanotube particle, a nanowire particle, a nanofiber particle, a nanoplate particle, and/or the like.

[0553] Because the energy band gap of the quantum dot may be adjusted by controlling the size of the quantum dots, light having one or more suitable wavelength bands may be obtained from a quantum dot-containing emission layer. Accordingly, by utilizing quantum dots of different sizes, a light-emitting device that emits light of one or more suitable wavelengths may be implemented. In one or more embodiments, the sizes of the quantum dots may be selected to enable the quantum dots to emit red light, green light, and/or blue light. In some embodiments, the quantum dots with suitable sizes may be configured to emit white light by combination of light of one or more suitable colors.

Electron Transport Region in Interlayer 130

[0554] The electron transport region may have: i) a single-layer structure including (e.g., consisting of) a single layer including (e.g., consisting of) a single material, ii) a single-layer structure including (e.g., consisting of) a single layer including (e.g., consisting of) multiple materials that are different from each other, or iii) a multi-layer structure including multiple layers including multiple materials that are different from each other.

[0555] The electron transport region may include a buffer layer, a hole blocking layer, an electron control layer, an electron transport layer, an electron injection layer, or any combination thereof.

[0556] For example, in one or more embodiments, the electron transport region may have an electron transport layer/electron injection layer structure, a hole-blocking layer/electron transport layer/electron injection layer structure, an electron control layer/electron transport layer/electron injection layer structure, a buffer layer/electron transport layer/electron injection layer structure, and/or the like, wherein constituent layers of each structure are sequentially stacked from the emission layer 130 in each stated order.

[0557] The electron transport region (e.g., a buffer layer, a hole blocking layer, an electron control layer, or an electron transport layer in the electron transport region) may include a metal-free compound including at least one electron-deficient nitrogen-containing C.sub.1-C.sub.60 heterocyclic group.

[0558] For example, in one or more embodiments, the electron transport region may include a compound represented by Formula 601:

[Ar.sub.601].sub.xe11-[(L.sub.601).sub.xe1-R.sub.601].sub.xe21,Formula 601 [0559] wherein, in Formula 601, [0560] Ar.sub.601 and L.sub.601 may each independently be a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, [0561] xe11 may be 1, 2, or 3, [0562] xe1 may be 0, 1, 2, 3, 4, or 5, [0563] R.sub.601 may be a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, Si(Q.sub.601)(Q.sub.602)(Q.sub.603), C(O)(Q.sub.601), S(O).sub.2(Q.sub.601), or P(O)(Q.sub.601)(Q.sub.602), [0564] Q.sub.601 to Q.sub.603 may each be the same as described with respect to Q.sub.1, [0565] xe21 may be 1, 2, 3, 4, or 5, and [0566] at least one selected from among Ar.sub.601, L.sub.601, and R.sub.601 may each independently be a electron-deficient nitrogen-containing C.sub.1-C.sub.60 heterocyclic group that is unsubstituted or substituted with at least one R.sub.10a.

[0567] For example, in some embodiments, when xe11 in Formula 601 is 2 or more, two or more Ar.sub.601(s) may be linked to each other via a single bond.

[0568] In one or more embodiments, Ar.sub.601 in Formula 601 may be a substituted or unsubstituted anthracene group.

[0569] In one or more embodiments, the electron transport region may include a compound represented by Formula 601-1:

##STR00292## [0570] wherein, in Formula 601-1, [0571] X.sub.614 may be N or C(R.sub.614), X.sub.615 may be N or C(R.sub.615), X.sub.616 may be N or C(R.sub.616), and at least one selected from among X.sub.614 to X.sub.616 may be N, [0572] L.sub.611 to L.sub.613 may each be the same as described with respect to L.sub.601, [0573] xe611 to xe613 may each be the same as described with respect to xe1, [0574] R.sub.611 to R.sub.613 may each be the same as described with respect to R.sub.601, and [0575] R.sub.614 to R.sub.616 may each independently be hydrogen, deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a, or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a.

[0576] For example, in some embodiments, xe1 and xe611 to xe613 in Formulae 601 and 601-1 may each independently be 0, 1, or 2.

[0577] In one or more embodiments, the electron transport region may include: at least one selected from among Compounds ET1 to ET45; 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP); 4,7-diphenyl-1,10-phenanthroline (Bphen); tris(8-hydroxyquinolinato)aluminum (Alq.sub.3); bis(2-methyl-8-quinolinolato-N1,O8)-(1,1-biphenyl-4-olato)aluminum (BAlq); 3-(4-biphenyl)-4-phenyl-5-tert-butylphenyl-1,2,4-triazole (TAZ); 4-(naphthalen-1-yl)-3,5-diphenyl-4H-1,2,4-triazole (NTAZ); or any combination thereof:

##STR00293## ##STR00294## ##STR00295## ##STR00296## ##STR00297## ##STR00298## ##STR00299## ##STR00300## ##STR00301## ##STR00302## ##STR00303## ##STR00304## ##STR00305## ##STR00306##

[0578] A thickness of the electron transport region may be in a range of about 100 to about 5,000 , for example, about 160 to about 4,000 . When the electron transport region includes a buffer layer, a hole blocking layer, an electron control layer, an electron transport layer, or any combination thereof, a thickness of the buffer layer, the hole blocking layer, or the electron control layer may each independently be in a range of about 20 to about 1,000 , for example, about 30 to about 300 , and a thickness of the electron transport layer may be in a range of about 100 to about 1,000 , for example, about 150 to about 500 . When the thicknesses of the buffer layer, the hole blocking layer, the electron control layer, the electron transport layer, and/or the electron transport region are within these ranges, satisfactory electron transporting characteristics may be obtained without a substantial increase in driving voltage.

[0579] In one or more embodiments, the electron transport region (e.g., an electron transport layer in the electron transport region) may further include, in addition to the aforementioned materials, a metal-containing material.

[0580] The metal-containing material may include an alkali metal complex, an alkaline earth metal complex, or any combination thereof. A metal ion of the alkali metal complex may be a Li ion, a Na ion, a K ion, a Rb ion, or a Cs ion, and a metal ion of the alkaline earth metal complex may be a Be ion, a Mg ion, a Ca ion, a Sr ion, or a Ba ion. A ligand coordinated with the metal ion of the alkali metal complex or the metal ion of the alkaline earth-metal complex may include a hydroxyquinoline, a hydroxyisoquinoline, a hydroxybenzoquinoline, a hydroxyacridine, a hydroxyphenanthridine, a hydroxyphenyloxazole, a hydroxyphenylthiazole, a hydroxyphenyloxadiazole, a hydroxyphenylthiadiazole, a hydroxyphenylpyridine, a hydroxyphenylbenzimidazole, a hydroxyphenylbenzothiazole, a bipyridine, a phenanthroline, a cyclopentadiene, or any combination thereof.

[0581] For example, in some embodiments, the metal-containing material may include a Li complex. The Li complex may include, for example, Compound ET-D1 (LiQ) or ET-D2:

##STR00307##

[0582] In one or more embodiments, the electron transport region may include an electron injection layer that facilitates the injection of electrons from the second electrode 150. The electron injection layer may directly contact the second electrode 150.

[0583] The electron injection layer may have: i) a single-layer structure including (e.g., consisting of) a single layer including (e.g., consisting of) a single material, ii) a single-layer structure including (e.g., consisting of) a single layer including (e.g., consisting of) multiple layers that are different from each other, or iii) a multi-layer structure including multiple layers including multiple materials that are different from each other.

[0584] The electron injection layer may include an alkali metal, alkaline earth metal, a rare earth metal, an alkali metal-containing compound, an alkaline earth metal-containing compound, a rare earth metal-containing compound, an alkali metal complex, an alkaline earth metal complex, a rare earth metal complex, or any combination thereof.

[0585] The alkali metal may include Li, Na, K, Rb, Cs, or any combination thereof. The alkaline earth metal may include Mg, Ca, Sr, Ba, or any combination thereof. The rare earth metal may include Sc, Y, Ce, Tb, Yb, Gd, or any combination thereof.

[0586] The alkali metal-containing compound, the alkaline earth metal-containing compound, and the rare earth metal-containing compound may be one or more oxides, one or more halides (e.g., fluorides, chlorides, bromides, and/or iodides), and/or one or more tellurides of the alkali metal, the alkaline earth metal, and the rare earth metal, respectively, or any combination thereof.

[0587] The alkali metal-containing compound may include: alkali metal oxides, such as Li.sub.2O, Cs.sub.2O, K.sub.2O, etc.; alkali metal halides, such as LiF, NaF, CsF, KF, LiI, NaI, CsI, KI, etc.; or any combination thereof. The alkaline earth metal-containing compound may include an alkaline earth metal compound, such as BaO, SrO, CaO, Ba.sub.xSr.sub.1-xO (wherein x is a real number satisfying the condition of 0<x<1), Ba.sub.xCa.sub.1-xO (wherein x is a real number satisfying the condition of 0<x<1), and/or the like. The rare earth metal-containing compound may include YbF.sub.3, ScF.sub.3, SC.sub.2O.sub.3, Y.sub.2O.sub.3, Ce.sub.2O.sub.3, GdF.sub.3, TbF.sub.3, YbI.sub.3, ScI.sub.3, TbI.sub.3, or any combination thereof. In one or more embodiments, the rare earth metal-containing compound may include lanthanide metal tellurides. Non-limiting examples of the lanthanide metal telluride may include LaTe, CeTe, PrTe, NdTe, PmTe, SmTe, EuTe, GdTe, TbTe, DyTe, HoTe, ErTe, TmTe, YbTe, LuTe, La.sub.2Te.sub.3, Ce.sub.2Te.sub.3, Pr.sub.2Te.sub.3, Nd.sub.2Te.sub.3, Pm.sub.2Te.sub.3, Sm.sub.2Te.sub.3, Eu.sub.2Te.sub.3, Gd.sub.2Te.sub.3, Tb.sub.2Te.sub.3, Dy.sub.2Te.sub.3, Ho.sub.2Te.sub.3, Er.sub.2Te.sub.3, Tm.sub.2Te.sub.3, Yb.sub.2Te.sub.3, Lu.sub.2Te.sub.3, and/or the like.

[0588] The alkali metal complex, the alkaline earth-metal complex, and the rare earth metal complex may include i) one of metal ions of the alkali metal, one of metal ions of the alkaline earth metal, and one of metal ions of the rare earth metal, respectively, and ii) a ligand bonded to the metal ions, for example, a hydroxyquinoline, a hydroxyisoquinoline, a hydroxybenzoquinoline, a hydroxyacridine, a hydroxyphenanthridine, a hydroxyphenyloxazole, a hydroxyphenylthiazole, a hydroxyphenyloxadiazole, a hydroxyphenylthiadiazole, a hydroxyphenylpyridine, a hydroxyphenyl benzimidazole, a hydroxyphenylbenzothiazole, a bipyridine, a phenanthroline, a cyclopentadiene, or any combination thereof.

[0589] In one or more embodiments, the electron injection layer may include (e.g., consist of) an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal-containing compound, an alkaline earth metal-containing compound, a rare earth metal-containing compound, an alkali metal complex, an alkaline earth metal complex, a rare earth metal complex, or any combination thereof, as described above. In one or more embodiments, the electron injection layer may further include an organic material (e.g., the compound represented by Formula 601).

[0590] In one or more embodiments, the electron injection layer may include (e.g., consist of) i) an alkali metal-containing compound (e.g., an alkali metal halide), or ii) a) an alkali metal-containing compound (e.g., an alkali metal halide), and b) an alkali metal, an alkaline earth metal, a rare earth metal, or any combination thereof. For example, in some embodiments, the electron injection layer may be a KI:Yb co-deposited layer, an RbI:Yb co-deposited layer, a LiF:Yb co-deposited layer, and/or the like.

[0591] When the electron injection layer further includes an organic material, the alkali metal, the alkaline earth metal, the rare earth metal, the alkali metal-containing compound, the alkaline earth metal-containing compound, the rare earth metal-containing compound, the alkali metal complex, the alkaline earth-metal complex, the rare earth metal complex, or any combination thereof may be substantially uniformly or non-uniformly dispersed in a matrix including the organic material.

[0592] A thickness of the electron injection layer may be in a range of about 1 to about 100 , for example, about 3 to about 90 . When the thickness of the electron injection layer is within these ranges, satisfactory electron injection characteristics may be obtained without a substantial increase in driving voltage.

Second Electrode 150

[0593] The second electrode 150 may be arranged on the interlayer 130 having the aforementioned structure. The second electrode 150 may be a cathode, which is an electron injection electrode, and as a material for forming the second electrode 150, a metal, an alloy, an electrically conductive compound, or any combination thereof, each having a low-work function, may be utilized.

[0594] The second electrode 150 may include Li, Ag, Mg, Al, AlLi, Ca, MgIn, MgAg, Yb, AgYb, ITO, IZO, or any combination thereof. The second electrode 150 may be a transmissive electrode, a semi-transmissive electrode, or a reflective electrode.

[0595] The second electrode 150 may have a single-layer structure or a multi-layer structure including multiple layers.

Capping Layer

[0596] A first capping layer may be arranged outside (e.g., on) the first electrode 110, and/or a second capping layer may be arranged outside (e.g., on) the second electrode 150. In one or more embodiments, the light-emitting device 10 may have a structure in which the first capping layer, the first electrode 110, the interlayer 130, and the second electrode 150 are sequentially stacked in the stated order, a structure in which the first electrode 110, the interlayer 130, the second electrode 150, and the second capping layer are sequentially stacked in the stated order, or a structure in which the first capping layer, the first electrode 110, the interlayer 130, the second electrode 150, and the second capping layer are sequentially stacked in the stated order.

[0597] In some embodiments, light generated in the emission layer of the interlayer 130 of the light-emitting device 10 may be extracted toward the outside through the first electrode 110, which is a semi-transmissive electrode or a transmissive electrode, and the first capping layer. In some embodiments, light generated in the emission layer of the interlayer 130 of the light-emitting device 10 may be extracted toward the outside through the second electrode 150, which is a semi-transmissive electrode or a transmissive electrode, and the second capping layer.

[0598] The first capping layer and the second capping layer may increase external emission efficiency according to the principle of constructive interference. Accordingly, the light extraction efficiency of the light-emitting device 10 is increased, as a result, the luminescence efficiency of the light-emitting device 10 may be improved.

[0599] Each of the first capping layer and the second capping layer may include a material having a refractive index of 1.6 or more (e.g., at 589 nm).

[0600] The first capping layer and the second capping layer may each independently be an organic capping layer including an organic material, an inorganic capping layer including an inorganic material, or an organic-inorganic composite capping layer including an organic material and an inorganic material.

[0601] At least one of the first capping layer or the second capping layer may (e.g., the first capping layer and the second capping layer may each independently) include a carbocyclic compound, a heterocyclic compound, an amine group-containing compound, a porphine derivative, a phthalocyanine derivative, a naphthalocyanine derivative, an alkali metal complex, an alkaline earth metal complex, or any combination thereof. The carbocyclic compound, the heterocyclic compound, and the amine group-containing compound may each optionally be substituted with a substituent including O, N, S, Se, Si, F, Cl, Br, I, or any combination thereof. In one or more embodiments, at least one of the first capping layer or the second capping layer may (e.g., the first capping layer and the second capping layer may each independently) include an amine group-containing compound.

[0602] In one or more embodiments, at least one of the first capping layer or the second capping layer may (e.g., the first capping layer and the second capping layer may each independently) include a compound represented by Formula 201, a compound represented by Formula 202, or any combination thereof.

[0603] In one or more embodiments, at least one of the first capping layer or the second capping layer may (e.g., the first capping layer and the second capping layer may each independently) include at least one selected from among Compounds HT28 to HT33, at least one selected from among Compounds CP1 to CP6, -NPB, or any combination thereof:

##STR00308##

Film

[0604] The organometallic compound represented by Formula 1 may be included in one or more suitable films. Accordingly, one or more embodiments of the present disclosure provide a film including the organometallic compound represented by Formula 1. The film may be, for example, an optical member (or a light control element) (for example, a color filter, a color conversion member, a capping layer, a light extraction efficiency enhancement layer, a selective light absorbing layer, a polarizing layer, a quantum dot-containing layer, or like), a light blocking member (for example, a light reflective layer, a light absorbing layer, and/or the like), and/or a protective member (for example, an insulating layer, a dielectric layer, and/or the like).

Electronic Apparatus

[0605] The light-emitting device may be included in one or more suitable electronic apparatuses. For example, in one or more embodiments, the electronic apparatus including the light-emitting device may be a light-emitting apparatus, an authentication apparatus, and/or the like.

[0606] In one or more embodiments, the electronic apparatus (e.g., a light-emitting apparatus) may further include, in addition to the light-emitting device, i) a color filter, ii) a color conversion layer, or iii) a color filter and a color conversion layer. The color filter and/or the color conversion layer may be arranged in at least one direction in which light emitted from the light-emitting device travels. For example, in some embodiments, light emitted from the light-emitting device may be blue light, green light, or white light (e.g., combined white light). A description of the light-emitting device may be the same as described herein. In some embodiments, the color conversion layer may include quantum dots.

[0607] The electronic apparatus may include a first substrate. The first substrate may include a plurality of subpixel areas, the color filter may include a plurality of color filter areas respectively corresponding to the subpixel areas, and the color conversion layer may include a plurality of color conversion areas respectively corresponding to the subpixel areas.

[0608] A pixel-defining film may be arranged among the subpixel areas to define each of the subpixel areas.

[0609] The color filter may further include a plurality of color filter areas and light-shielding patterns thereon, and the color conversion layer may further include a plurality of color conversion areas and light-shielding patterns thereon.

[0610] The plurality of color filter areas (or the plurality of color conversion areas) may include a first area configured to emit first color light, a second area configured to emit second color light, and/or a third area configured to emit third color light, wherein the first color light, the second color light, and/or the third color light may have different maximum emission wavelengths from one another. For example, in one or more embodiments, the first color light may be red light, the second color light may be green light, and the third color light may be blue light. For example, in one or more embodiments, the plurality of color filter areas (or the plurality of color conversion areas) may include quantum dots. In some embodiments, the first area may include red quantum dots to emit red light, and the second area may include green quantum dots to emit green light, whereas the third area may not include (e.g., may exclude any) quantum dots. A detailed description of the quantum dot may be the same as described herein. The first area, the second area, and/or the third area may each further include a scatter.

[0611] For example, in one or more embodiments, the light-emitting device may be to emit first light, the first area may be to absorb the first light to emit first-first color light, the second area may be to absorb the first light to emit second-first color light, and the third area may be to absorb the first light to emit third-first color light. In this regard, the first-first color light, the second-first color light, and the third-first color light may have different maximum emission wavelengths from one another. In some embodiments, the first light may be blue light, the first-first color light may be red light, the second-first color light may be green light, and the third-first color light may be blue light.

[0612] In one or more embodiments, the electronic apparatus may further include a thin-film transistor, in addition to the aforementioned light-emitting device. The thin-film transistor may include a source electrode, a drain electrode, and an activation layer, wherein one selected from among the source electrode and the drain electrode may be electrically connected to the first electrode or the second electrode of the light-emitting device.

[0613] The thin-film transistor may further include a gate electrode, a gate insulating film, and/or the like.

[0614] The activation layer may include crystalline silicon, amorphous silicon, an organic semiconductor, an oxide semiconductor, and/or the like.

[0615] In one or more embodiments, the electronic apparatus may further include a sealing portion for sealing the light-emitting device. The sealing portion may be arranged between the color filter and/or the color conversion layer and the light-emitting device. The sealing portion allows light from the light-emitting device to be extracted to the outside, and concurrently (e.g., simultaneously) prevents ambient air and moisture from penetrating into the light-emitting device. The sealing portion may be a sealing substrate including a transparent glass substrate or a plastic substrate. The sealing portion may be a thin-film encapsulation layer including at least one layer of an organic layer and/or an inorganic layer. When the sealing portion is a thin-film encapsulation layer, the electronic apparatus may be flexible.

[0616] Various functional layers may be additionally arranged on the sealing portion, in addition to the color filter and/or the color conversion layer, according to the utilization of the electronic apparatus. Non-limiting examples of the functional layers may include a touch screen layer, a polarizing layer, and/or the like. The touch screen layer may be a pressure-sensitive touch screen layer, a capacitive touch screen layer, or an infrared touch screen layer.

[0617] The authentication apparatus may be, for example, a biometric authentication apparatus that authenticates an individual by utilizing biometric information of a living body (e.g., fingertips, pupils, etc.). The authentication apparatus may further include, in addition to the light-emitting device as described above, a biometric information collector.

[0618] The electronic apparatus may be applied to one or more of displays, light sources, lighting, personal computers (e.g., mobile personal computers), mobile phones, digital cameras, electronic organizers, electronic dictionaries, electronic game machines, medical instruments (e.g., electronic thermometers, sphygmomanometers, blood glucose meters, pulse measurement devices, pulse wave measurement devices, electrocardiogram displays, ultrasonic diagnostic devices, or endoscope displays), fish finders, one or more suitable measuring instruments, meters (e.g., meters for a vehicle, an aircraft, and a vessel), projectors, and/or the like.

Electronic Equipment

[0619] The light-emitting device may be included in one or more suitable electronic equipment.

[0620] For example, the electronic equipment including the light-emitting device may be at least one of a flat panel display, a curved display, a computer monitor, a medical monitor, a television, a billboard, a light for indoor or outdoor lighting and/or signaling, a head-up display, a fully or partially transparent display, a flexible display, a rollable display, a foldable display, a stretchable display, a laser printer, a telephone, a mobile phone, a tablet, a phablet, a personal digital assistant (PDA), a wearable device, a laptop computer, a digital camera, a camcorder, a viewfinder, a micro display, a 3D display, a virtual or augmented-reality display, a vehicle, a video wall including multiple displays tiled together, a theater or stadium screen, a phototherapy device, or a signboard.

[0621] The light-emitting device may have excellent or suitable luminescence efficiency and long lifespan, and thus the electronic equipment including the light-emitting device may have desirable characteristics, such as high luminance, high resolution, and low power consumption.

Description of FIG. 2 and FIG. 3

[0622] FIG. 2 is a cross-sectional view showing a light-emitting apparatus as an example of the electronic apparatus according to one or more embodiments of the present disclosure.

[0623] The light-emitting apparatus of FIG. 2 may include a substrate 100, a thin-film transistor (TFT), a light-emitting device, and an encapsulation portion 300 that seals the light-emitting device.

[0624] The substrate 100 may be a flexible substrate, a glass substrate, or a metal substrate. A buffer layer 210 may be on (e.g., arranged on) the substrate 100. The buffer layer 210 may prevent or reduce penetration of impurities through the substrate 100, and provide a flat surface on the substrate 100.

[0625] The TFT may be on (e.g., arranged on) the buffer layer 210. The TFT may include an activation layer 220, a gate electrode 240, a source electrode 260, and a drain electrode 270.

[0626] The activation layer 220 may include an inorganic semiconductor, such as silicon or polysilicon, an organic semiconductor, or an oxide semiconductor, and may include a source region, a drain region, and a channel region.

[0627] A gate insulating film 230 for insulating the activation layer 220 from the gate electrode 240 may be on (e.g., arranged on) the activation layer 220, and the gate electrode 240 may be on (e.g., arranged on) the gate insulating film 230.

[0628] An interlayer insulating film 250 may be on (e.g., arranged on) the gate electrode 240. The interlayer insulating film 250 may be arranged between the gate electrode 240 and the source electrode 260 and between the gate electrode 240 and the drain electrode 270, to insulate these electrodes from one another.

[0629] The source electrode 260 and the drain electrode 270 may be on (e.g., arranged on) the interlayer insulating film 250. The interlayer insulating film 250 and the gate insulating film 230 may be formed to expose the source region and the drain region of the activation layer 220, and the source electrode 260 and the drain electrode 270 may be arranged in contact with the exposed portions of the source region and the drain region of the activation layer 220, respectively.

[0630] The TFT may be electrically connected to the light-emitting device to drive the light-emitting device, and may be covered and protected by a passivation layer 280. The passivation layer 280 may include an inorganic insulating film, an organic insulating film, or any combination thereof. The light-emitting device may be provided on the passivation layer 280. The light-emitting device may include a first electrode 110, an interlayer 130, and a second electrode 150.

[0631] The first electrode 110 may be on (e.g., arranged on) the passivation layer 280. The passivation layer 280 may be arranged to expose a portion of the drain electrode 270 without fully covering the drain electrode 270, and the first electrode 110 may be arranged to be connected to the exposed portion of the drain electrode 270.

[0632] A pixel defining layer 290 including an insulating material may be on (e.g., arranged on) the first electrode 110. The pixel defining layer 290 may expose a certain region of the first electrode 110, and the interlayer 130 may be formed in the exposed region of the first electrode 110. The pixel defining layer 290 may be a polyimide-based organic film or a polyacrylic-based organic film. In some embodiments, at least some layers of the interlayer 130 may extend beyond the upper portion of the pixel defining layer 290 to be arranged in the form of a common layer.

[0633] The second electrode 150 may be on (e.g., arranged on) the interlayer 130, and a second capping layer 170 may be additionally formed on the second electrode 150. The second capping layer 170 may be formed to cover the second electrode 150.

[0634] The encapsulation portion 300 may be on (e.g., arranged on) the second capping layer 170. The encapsulation portion 300 may be arranged on the light-emitting device to protect the light-emitting device from moisture and/or oxygen. The encapsulation portion 300 may include: an inorganic film including silicon nitride (SiN.sub.x), silicon oxide (SiO.sub.x), indium tin oxide, indium zinc oxide, or any combination thereof; an organic film including polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyimide, polyethylene sulfonate, polyoxymethylene, polyarylate, hexamethyldisiloxane, an acrylic resin (for example, polymethyl methacrylate, polyacrylic acid, and/or the like), an epoxy-based resin (for example, aliphatic glycidyl ether (AGE), and/or the like), or any combination thereof; or any combination of the inorganic films and the organic films.

[0635] FIG. 3 is a cross-sectional view of a light-emitting apparatus as an example of the electronic apparatus according to one or more embodiments of the present disclosure.

[0636] The light-emitting apparatus of FIG. 3 is substantially the same as the light-emitting apparatus of FIG. 2, except that a light-shielding pattern 500 and a functional region 400 are additionally arranged on the encapsulation portion 300. The functional region 400 may be i) a color filter area, ii) a color conversion area, or iii) a combination of the color filter area and the color conversion area. In one or more embodiments, the light-emitting device included in the light-emitting apparatus of FIG. 3 may be a tandem light-emitting device.

Description of FIG. 4

[0637] FIG. 4 is a schematic perspective view of electronic equipment 1 including the light-emitting device according to one or more embodiments. The electronic equipment 1 may be, as a device apparatus that displays a moving image or still image, a portable electronic equipment, such as a mobile phone, a smart phone, a tablet personal computer (PC), a mobile communication terminal, an electronic notebook, an electronic book, a portable multimedia player (PMP), a navigation, or a ultra-mobile PC (UMPC), as well as one or more suitable products, such as a television, a laptop, a monitor, a billboard, or an Internet of things (IOT). The electronic equipment 1 may be such a product above or a part thereof. In some embodiments, the electronic equipment 1 may be a wearable device, such as a smart watch, a watch phone, a glasses-type or kind display, or a head mounted display (HMD), or a part of the wearable device. However, embodiments of the present disclosure are not limited thereto. For example, in one or more embodiments, the electron equipment 1 may include a dashboard of a vehicle, a center information display on a center fascia or dashboard of a vehicle, a room mirror display replacing a side mirror of a vehicle, an entertainment display arranged for the rear seat of a vehicle or arranged on the back of the front seat thereof, a head-up display (HUD) installed at the front of a vehicle or projected on a front window glass, and/or a computer generated hologram augmented reality head up display (CGH AR HUD). FIG. 4 illustrates an embodiment in which the electronic equipment 1 is a smart phone for convenience of explanation.

[0638] The electronic equipment 1 may include a display area DA and a non-display area NDA outside the display area DA. A display device of the electronic equipment 1 may implement an image through an array of a plurality of pixels that are two-dimensionally arranged in the display area DA.

[0639] The non-display area NDA is an area that does not display an image, and may entirely surround the display area DA. On the non-display area NDA, a driver for providing electrical signals or power to display devices arranged on the display area DA may be arranged. On the non-display area NDA, a pad, which is an area to which an electronic element or a printing circuit board, may be electrically connected may be arranged.

[0640] In the electronic equipment 1, a length in the x-axis direction and a length in the y-axis direction may be different from each other. In one or more embodiments, as shown in FIG. 4, the length in the x-axis direction may be shorter than the length in the y-axis direction. In one or more embodiments, the length in the x-axis direction may be substantially the same as the length in the y-axis direction. In one or more embodiments, the length in the x-axis direction may be longer than the length in the y-axis direction.

Descriptions of FIGS. 5 and 6A to 6C

[0641] FIG. 5 is a schematic view of an exterior of a vehicle 1000 as an electronic apparatus including a light-emitting device according to one or more embodiments. FIGS. 6A to 6C are each a schematic view of an interior of the vehicle 1000 according to one or more embodiments.

[0642] Referring to FIGS. 5, 6A, 6B, and 6C, the vehicle 1000 may refer to one or more suitable apparatuses for moving an object to be transported, such as a human, an object, or an animal, from a departure point to a destination point. The vehicle 1000 may include a vehicle traveling on a road or a track, a vessel moving over the sea or a river, an airplane flying in the sky utilizing the action of air, and/or the like.

[0643] In one or more embodiments, the vehicle 1000 may travel on a road or a track. The vehicle 1000 may move in a set or predetermined direction according to rotation of at least one wheel thereof. For example, the vehicle 1000 may include a three-wheeled or four-wheeled vehicle, a construction machine, a two-wheeled vehicle, a prime mover device, a bicycle, or a train running on a track.

[0644] The vehicle 1000 may include a body having an interior and an exterior, and a chassis in which mechanical apparatuses necessary for driving are installed as other parts except for the body. The exterior of the body may include a front panel, a bonnet, a roof panel, a rear panel, a trunk, a pillar provided at a boundary between doors, and/or the like. The chassis of the vehicle 1000 may include a power generating device, a power transmitting device, a driving device, a steering device, a braking device, a suspension device, a transmission device, a fuel device, front and rear left and right wheels, and/or the like.

[0645] The vehicle 1000 may include a side window glass 1100, a front window glass 1200, a side mirror 1300, a cluster 1400, a center fascia 1500, a passenger seat dashboard 1600, and a display device 2.

[0646] The side window glass 1100 and the front window glass 1200 may be partitioned by a pillar arranged between the side window glass 1100 and the front window glass 1200.

[0647] The side window glass 1100 may be installed on a side of the vehicle 1000. In some embodiments, the side window glass 1100 may be installed on a door of the vehicle 1000. A plurality of side window glasses 1100 may be provided and may face each other. In some embodiments, the side window glass 1100 may include a first side window glass 1110 and a second side window glass 1120. In some embodiments, the first side window glass 1110 may be arranged adjacent to the cluster 1400. The second side window glass 1120 may be arranged adjacent to the passenger seat dashboard 1600.

[0648] In one or more embodiments, the side window glasses 1100 may be spaced apart from each other in the x-direction or the x-direction (the direction opposite the x direction). For example, in some embodiments, the first side window glass 1110 and the second side window glass 1120 may be spaced apart from each other in the x direction or the x direction. In other words, an imaginary straight line L connecting the side window glasses 1100 may extend in the x-direction or the x-direction. For example, an imaginary straight line L connecting the first side window glass 1110 and the second side window glass 1120 to each other may extend in the x direction or the x direction.

[0649] The front window glass 1200 may be installed in the front of the vehicle 1000. The front window glass 1200 may be arranged between the side window glasses 1100 facing each other.

[0650] The side mirror 1300 may provide a rear view of the vehicle 1000. The side mirror 1300 may be installed on the exterior of the vehicle body. In one or more embodiments, a plurality of side mirrors 1300 may be provided. Any one of the plurality of side mirrors 1300 may be arranged outside the first side window glass 1110. The other one of the plurality of side mirrors 1300 may be arranged outside the second side window glass 1120.

[0651] The cluster 1400 may be arranged in front of the steering wheel. The cluster 1400 may include a tachometer, a speedometer, a coolant thermometer, a fuel gauge turn indicator, a high beam indicator, a warning light, a seat belt warning lamp, an odometer, an automatic shift selector indicator, a door open warning light, an engine oil warning light, and/or a low fuel warning light.

[0652] The center fascia 1500 may include a control panel on which a plurality of buttons for adjusting an audio device, an air conditioning device, and/or a heater of a seat are disposed. The center fascia 1500 may be arranged on one side of the cluster 1400.

[0653] The passenger seat dashboard 1600 may be spaced apart from the cluster 1400 with the center fascia 1500 arranged therebetween. In some embodiments, the cluster 1400 may be arranged to correspond to a driver seat, and the passenger seat dashboard 1600 may be disposed to correspond to a passenger seat. In some embodiments, the cluster 1400 may be adjacent to the first side window glass 1110, and the passenger seat dashboard 1600 may be adjacent to the second side window glass 1120.

[0654] In one or more embodiments, the display device 2 may include a display panel 3, and the display panel 3 may display an image. The display device 2 may be arranged inside the vehicle 1000. In some embodiments, the display device 2 may be arranged between the side window glasses 1100 facing each other. The display device 2 may be arranged on at least one of the cluster 1400, the center fascia 1500, or the passenger seat dashboard 1600.

[0655] The display device 2 may include an organic light-emitting display device, an inorganic electroluminescent display device, a quantum dot display device, and/or the like. Hereinafter, as the display device 2 according to one or more embodiments, an organic light-emitting display apparatus including the aforementioned light-emitting device will be described as an example, but one or more suitable types (kinds) of the aforementioned display apparatus may be utilized in embodiments.

[0656] Referring to FIG. 6A, in one or more embodiments, the display device 2 may be arranged on the center fascia 1500. In some embodiments, the display device 2 may display navigation information. In some embodiments, the display device 2 may display audio, video, or information regarding vehicle settings.

[0657] Referring to FIG. 6B, in one or more embodiments, the display device 2 may be arranged on the cluster 1400. When the display device 2 is arranged on the cluster 1400, the cluster 1400 may display driving information and/or the like through the display device 2. For example, the cluster 1400 may be implemented digitally. The digital cluster 1400 may display vehicle information and driving information as images. For example, a needle and a gauge of a tachometer and one or more suitable warning light icons may be displayed by a digital signal.

[0658] Referring to FIG. 6C, in one or more embodiments, the display device 2 may be arranged on the passenger seat dashboard 1600. The display device 2 may be embedded in the passenger seat dashboard 1600 or arranged on the passenger seat dashboard 1600. In some embodiments, the display device 2 arranged on the passenger seat dashboard 1600 may display an image related to information displayed on the cluster 1400 and/or information displayed on the center fascia 1500. In one or more embodiments, the display device 2 arranged on the passenger seat dashboard 1600 may display information different from information displayed on the cluster 1400 and/or information displayed on the center fascia 1500.

Manufacturing Method

[0659] The layers constituting the hole transport region, the emission layer, and the layers constituting the electron transport region may each be formed in a certain region by utilizing one or more suitable methods such as vacuum deposition, spin coating, casting, Langmuir-Blodgett (LB) deposition, ink-jet printing, laser-printing, laser-induced thermal imaging, and/or the like.

[0660] When the layers constituting the hole transport region, the emission layer, and the layers constituting the electron transport region are each formed by vacuum deposition, the deposition may be performed at a deposition temperature in a range of about 100 C. to about 500 C., at a vacuum degree in a range of about 10-8 torr to about 10-3 torr, and at a deposition speed in a range of about 0.01 /sec to about 100 /see, depending on a material to be included in a layer to be formed and the structure of a layer to be formed.

Definition of Terms

[0661] The term C.sub.3-C.sub.60 carbocyclic group as utilized herein refers to a cyclic group including (e.g., consisting of) carbon only as a ring-forming atom and having three to sixty carbon atoms, and the term C.sub.1-C.sub.60 heterocyclic group as utilized herein refers to a cyclic group that has 1 to 60 carbon atoms and further has, in addition to carbon, a heteroatom as a ring-forming atom. The C.sub.3-C.sub.60 carbocyclic group and the C.sub.1-C.sub.60 heterocyclic group may each be: a monocyclic group including (e.g., consisting of) one (e.g., only one) ring; or a polycyclic group in which two or more rings are condensed with each other. For example, the number of ring-forming atoms of the C.sub.1-C.sub.60 heterocyclic group may be from 3 to 61.

[0662] The term cyclic group as utilized herein may include both (e.g., simultaneously) the C.sub.3-C.sub.60 carbocyclic group and the C.sub.1-C.sub.60 heterocyclic group.

[0663] The term electron-rich C.sub.3-C.sub.60 cyclic group as utilized herein refers to a cyclic group that has 3 to 60 carbon atoms and does not include *N* as a ring-forming moiety, and the term electron-deficient nitrogen-containing C.sub.1-C.sub.60 heterocyclic group as utilized herein refers to a heterocyclic group that has 1 to 60 carbon atoms and includes *N* as a ring-forming moiety.

[0664] For example, [0665] the C.sub.3-C.sub.60 carbocyclic group may be i) Group T1 or ii) a condensed cyclic group in which two or more of Group T1 are condensed with each other (for example, a cyclopentadiene group, an adamantane group, a norbornane group, a benzene group, a pentalene group, a naphthalene group, an azulene group, an indacene group, an acenaphthylene group, a phenalene group, a phenanthrene group, an anthracene group, a fluoranthene group, a triphenylene group, a pyrene group, a chrysene group, a perylene group, a pentaphene group, a heptalene group, a naphthacene group, a picene group, a hexacene group, a pentacene group, a rubicene group, a coronene group, an ovalene group, an indene group, a fluorene group, a spiro-bifluorene group, a benzofluorene group, an indenophenanthrene group, or an indenoanthracene group), [0666] the C.sub.1-C.sub.60 heterocyclic group may be i) Group T2, ii) a condensed cyclic group in which two or more of Group T2 are condensed with each other, or iii) a condensed cyclic group in which at least one Group T2 and at least one Group T1 are condensed with each other (e.g., a pyrrole group, a thiophene group, a furan group, an indole group, a benzoindole group, a naphthoindole group, an isoindole group, a benzoisoindole group, a naphthoisoindole group, a benzosilole group, a benzothiophene group, a benzofuran group, a carbazole group, a dibenzosilole group, a dibenzothiophene group, a dibenzofuran group, an indenocarbazole group, an indolocarbazole group, a benzofurocarbazole group, a benzothienocarbazole group, a benzosilolocarbazole group, a benzoindolocarbazole group, a benzocarbazole group, a benzonaphthofuran group, a benzonaphthothiophene group, a benzonaphthosilole group, a benzofurodibenzofuran group, a benzofurodibenzothiophene group, a benzothienodibenzothiophene group, a pyrazole group, an imidazole group, a triazole group, an oxazole group, an isoxazole group, an oxadiazole group, a thiazole group, an isothiazole group, a thiadiazole group, a benzopyrazole group, a benzimidazole group, a benzoxazole group, a benzoisoxazole group, a benzothiazole group, a benzoisothiazole group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, a quinoline group, an isoquinoline group, a benzoquinoline group, a benzoisoquinoline group, a quinoxaline group, a benzoquinoxaline group, a quinazoline group, a benzoquinazoline group, a phenanthroline group, a cinnoline group, a phthalazine group, a naphthyridine group, an imidazopyridine group, an imidazopyrimidine group, an imidazotriazine group, an imidazopyrazine group, an imidazopyridazine group, an azacarbazole group, an azafluorene group, an azadibenzosilole group, an azadibenzothiophene group, an azadibenzofuran group, etc.), [0667] the electron-rich C.sub.3-C.sub.60 cyclic group may be i) Group T1, ii) a condensed cyclic group in which two or more of Group T1 are condensed with each other, iii) Group T3, iv) a condensed cyclic group in which two or more of Group T3 are condensed with each other, or v) a condensed cyclic group in which at least one Group T3 and at least one Group T1 are condensed with each other (for example, the C.sub.3-C.sub.60 carbocyclic group, a 1H-pyrrole group, a silole group, a borole group, a 2H-pyrrole group, a 3H-pyrrole group, a thiophene group, a furan group, an indole group, a benzoindole group, a naphthoindole group, an isoindole group, a benzoisoindole group, a naphthoisoindole group, a benzosilole group, a benzothiophene group, a benzofuran group, a carbazole group, a dibenzosilole group, a dibenzothiophene group, a dibenzofuran group, an indenocarbazole group, an indolocarbazole group, a benzofurocarbazole group, a benzothienocarbazole group, a benzosilolocarbazole group, a benzoindolocarbazole group, a benzocarbazole group, a benzonaphthofuran group, a benzonaphthothiophene group, a benzonaphthosilole group, a benzofurodibenzofuran group, a benzofurodibenzothiophene group, a benzothienodibenzothiophene group, and/or the like), [0668] the electron-deficient nitrogen-containing C.sub.1-C.sub.60 heterocyclic group may be i) Group T4, ii) a condensed cyclic group in which two or more of Group T4 are condensed with each other, iii) a condensed cyclic group in which at least one Group T4 and at least one Group T1 are condensed with each other, iv) a condensed cyclic group in which at least one Group T4 and at least one Group T3 are condensed with each other, or v) a condensed cyclic group in which at least one Group T4, at least one Group T1, and at least one Group T3 are condensed with one another (e.g., a pyrazole group, an imidazole group, a triazole group, an oxazole group, an isoxazole group, an oxadiazole group, a thiazole group, an isothiazole group, a thiadiazole group, a benzopyrazole group, a benzimidazole group, a benzoxazole group, a benzoisoxazole group, a benzothiazole group, a benzoisothiazole group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, a quinoline group, an isoquinoline group, a benzoquinoline group, a benzoisoquinoline group, a quinoxaline group, a benzoquinoxaline group, a quinazoline group, a benzoquinazoline group, a phenanthroline group, a cinnoline group, a phthalazine group, a naphthyridine group, an imidazopyridine group, an imidazopyrimidine group, an imidazotriazine group, an imidazopyrazine group, an imidazopyridazine group, an azacarbazole group, an azafluorene group, an azadibenzosilole group, an azadibenzothiophene group, an azadibenzofuran group, etc.), [0669] Group T1 may be a cyclopropane group, a cyclobutane group, a cyclopentane group, a cyclohexane group, a cycloheptane group, a cyclooctane group, a cyclobutene group, a cyclopentene group, a cyclopentadiene group, a cyclohexene group, a cyclohexadiene group, a cycloheptene group, an adamantane group, a norbornane (or bicyclo[2.2.1]heptane) group, a norbornene group, a bicyclo[1.1.1]pentane group, a bicyclo[2.1.1]hexane group, a bicyclo[2.2.2]octane group, or a benzene group, [0670] Group T2 may be a furan group, a thiophene group, a 1H-pyrrole group, a silole group, a borole group, a 2H-pyrrole group, a 3H-pyrrole group, an imidazole group, a pyrazole group, a triazole group, a tetrazole group, an oxazole group, an isoxazole group, an oxadiazole group, a thiazole group, an isothiazole group, a thiadiazole group, an azasilole group, an azaborole group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, a tetrazine group, a pyrrolidine group, an imidazolidine group, a dihydropyrrole group, a piperidine group, a tetrahydropyridine group, a dihydropyridine group, a hexahydropyrimidine group, a tetrahydropyrimidine group, a dihydropyrimidine group, a piperazine group, a tetrahydropyrazine group, a dihydropyrazine group, a tetrahydropyridazine group, or a dihydropyridazine group, [0671] Group T3 may be a furan group, a thiophene group, a 1H-pyrrole group, a silole group, or a borole group, and [0672] Group T4 may be a 2H-pyrrole group, a 3H-pyrrole group, an imidazole group, a pyrazole group, a triazole group, a tetrazole group, an oxazole group, an isoxazole group, an oxadiazole group, a thiazole group, an isothiazole group, a thiadiazole group, an azasilole group, an azaborole group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, or a tetrazine group.

[0673] The term cyclic group, C.sub.3-C.sub.60 carbocyclic group, C.sub.1-C.sub.60 heterocyclic group, electron-rich C.sub.3-C.sub.60 cyclic group, or electron-deficient nitrogen-containing C.sub.1-C.sub.60 heterocyclic group as utilized herein may refer to a group condensed to any cyclic group, a monovalent group, or a polyvalent group (e.g., a divalent group, a trivalent group, a tetravalent group, etc.) according to the structure of a formula for which the corresponding term is utilized. For example, the benzene group may be a benzo group, a phenyl group, a phenylene group, and/or the like, which may be easily understood by one of ordinary skill in the art according to the structure of a formula including the benzene group.

[0674] Depending on context, in the present disclosure, a divalent group may refer or be a polyvalent group (e.g., trivalent, tetravalent, etc., and not just divalent) per, e.g., the structure of a formula in connection with which of the terms are utilized.

[0675] Non-limiting examples of the monovalent C.sub.3-C.sub.60 carbocyclic group and the monovalent C.sub.1-C.sub.60 heterocyclic group may include a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.1-C.sub.10 heterocycloalkyl group, a C.sub.3-C.sub.10 cycloalkenyl group, a C.sub.1-C.sub.10 heterocycloalkenyl group, a C.sub.6-C.sub.60 aryl group, a C.sub.1-C.sub.60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group. Non-limiting examples of the divalent C.sub.3-C.sub.60 carbocyclic group and the divalent C.sub.1-C.sub.60 heterocyclic group are a C.sub.3-C.sub.10 cycloalkylene group, a C.sub.1-C.sub.10 heterocycloalkylene group, a C.sub.3-C.sub.10 cycloalkenylene group, a C.sub.1-C.sub.10 heterocycloalkenylene group, a C.sub.6-C.sub.60 arylene group, a C.sub.1-C.sub.60 heteroarylene group, a divalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted divalent non-aromatic condensed heteropolycyclic group.

[0676] The term C.sub.1-C.sub.60 alkyl group as utilized herein refers to a linear or branched aliphatic hydrocarbon monovalent group that has 1 to 60 carbon atoms, and non-limiting examples thereof may include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, an isobutyl group, a tert-butyl group, an n-pentyl group, a tert-pentyl group, a neopentyl group, an isopentyl group, a sec-pentyl group, a 3-pentyl group, a sec-isopentyl group, an n-hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group, an n-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptyl group, an n-octyl group, an isooctyl group, a sec-octyl group, a tert-octyl group, an n-nonyl group, an isononyl group, a sec-nonyl group, a tert-nonyl group, an n-decyl group, an isodecyl group, a sec-decyl group, and a tert-decyl group. The term C.sub.1-C.sub.60 alkylene group as utilized herein refers to a divalent group having substantially the same structure as the C.sub.1-C.sub.60 alkyl group.

[0677] The term C.sub.2-C.sub.60 alkenyl group as utilized herein refers to a monovalent hydrocarbon group having at least one carbon-carbon double bond in the middle or at the terminus of a C.sub.2-C.sub.60 alkyl group, and non-limiting examples thereof may include an ethenyl group, a propenyl group, a butenyl group, and/or the like. The term C.sub.2-C.sub.60 alkenylene group as utilized herein refers to a divalent group having substantially the same structure as the C.sub.2-C.sub.60 alkenyl group.

[0678] The term C.sub.2-C.sub.60 alkynyl group as utilized herein refers to a monovalent hydrocarbon group having at least one carbon-carbon triple bond in the middle or at the terminus of a C.sub.2-C.sub.60 alkyl group, and non-limiting examples thereof may include an ethynyl group, a propynyl group, and/or the like. The term C.sub.2-C.sub.60 alkynylene group as utilized herein refers to a divalent group having substantially the same structure as the C.sub.2-C.sub.60 alkynyl group.

[0679] The term C.sub.1-C.sub.60 alkoxy group as utilized herein refers to a monovalent group represented by OA.sub.101 (wherein A.sub.101 is a C.sub.1-C.sub.60 alkyl group), and non-limiting examples thereof may include a methoxy group, an ethoxy group, an isopropyloxy group, and/or the like.

[0680] The term C.sub.3-C.sub.10 cycloalkyl group as utilized herein refers to a monovalent saturated hydrocarbon cyclic group having 3 to 10 carbon atoms, and non-limiting examples thereof may include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group (or bicyclo[2.2.1]heptyl group), a bicyclo[1.1.1]pentyl group, a bicyclo[2.1.1]hexyl group, a bicyclo[2.2.2]octyl group, and/or the like. The term C.sub.3-C.sub.10 cycloalkylene group as utilized herein refers to a divalent group having substantially the same structure as the C.sub.3-C.sub.10 cycloalkyl group.

[0681] The term C.sub.1-C.sub.10 heterocycloalkyl group as utilized herein refers to a monovalent cyclic group of 1 to 10 carbon atoms, further including, in addition to carbon atoms, at least one heteroatom as ring-forming atoms, and non-limiting examples thereof may include a 1,2,3,4-oxatriazolidinyl group, a tetrahydrofuranyl group, a tetrahydrothiophenyl group, and/or the like. The term C.sub.1-C.sub.10 heterocycloalkylene group as utilized herein refers to a divalent group having substantially the same structure as the C.sub.1-C.sub.10 heterocycloalkyl group.

[0682] The term C.sub.3-C.sub.10 cycloalkenyl group as utilized herein refers to a monovalent cyclic group that 3 to 10 carbon atoms, at least one carbon-carbon double bond in the ring thereof, and no aromaticity, and non-limiting examples thereof may include a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, and/or the like. The term C.sub.3-C.sub.10 cycloalkenylene group as utilized herein refers to a divalent group having substantially the same structure as the C.sub.3-C.sub.10 cycloalkenyl group.

[0683] The term C.sub.1-C.sub.10 heterocycloalkenyl group as utilized herein refers to a monovalent cyclic group of 1 to 10 carbon atoms, further including, in addition to carbon atoms, at least one heteroatom as ring-forming atoms and at least one carbon-carbon double bond in the cyclic structure thereof. Non-limiting examples of the C.sub.1-C.sub.10 heterocycloalkenyl group may include a 4,5-dihydro-1,2,3,4-oxatriazolyl group, a 2,3-dihydrofuranyl group, a 2,3-dihydrothiophenyl group, and/or the like. The term C.sub.1-C.sub.10 heterocycloalkenylene group as utilized herein refers to a divalent group having substantially the same structure as the C.sub.1-C.sub.10 heterocycloalkenyl group.

[0684] The term C.sub.6-C.sub.60 aryl group as utilized herein refers to a monovalent group having a carbocyclic aromatic system of 6 to 60 carbon atoms, and the term C.sub.6-C.sub.60 arylene group as utilized herein refers to a divalent group having a carbocyclic aromatic system of 6 to 60 carbon atoms. Non-limiting examples of the C.sub.6-C.sub.60 aryl group may include a phenyl group, a pentalenyl group, a naphthyl group, an azulenyl group, an indacenyl group, an acenaphthyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenyl group, a heptalenyl group, a naphthacenyl group, a picenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, and/or the like. When the C.sub.6-C.sub.60 aryl group and the C.sub.6-C.sub.60 arylene group each include two or more rings, the rings may be condensed with each other.

[0685] The term C.sub.1-C.sub.60 heteroaryl group as utilized herein refers to a monovalent group having a heterocyclic aromatic system of 1 to 60 carbon atoms, further including, in addition to carbon atoms, at least one heteroatom as ring-forming atoms. The term C.sub.1-C.sub.60 heteroarylene group as utilized herein refers to a divalent group having a heterocyclic aromatic system of 1 to 60 carbon atoms, further including, in addition to carbon atoms, at least one heteroatom as ring-forming atoms. Non-limiting examples of the C.sub.1-C.sub.60 heteroaryl group may include a pyridinyl group, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, a benzoquinolinyl group, an isoquinolinyl group, a benzoisoquinolinyl group, a quinoxalinyl group, a benzoquinoxalinyl group, a quinazolinyl group, a benzoquinazolinyl group, a cinnolinyl group, a phenanthrolinyl group, a phthalazinyl group, a naphthyridinyl group, and/or the like. When the C.sub.1-C.sub.60 heteroaryl group and the C.sub.1-C.sub.60 heteroarylene group each include two or more rings, the rings may be condensed with each other.

[0686] The term monovalent non-aromatic condensed polycyclic group as utilized herein refers to a monovalent group (for example, having 8 to 60 carbon atoms) having two or more rings condensed to each other, only carbon atoms as ring-forming atoms, and no aromaticity in the entire molecular structure as a whole. Non-limiting examples of the monovalent non-aromatic condensed polycyclic group may include an indenyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, an indenophenanthrenyl group, an indeno anthracenyl group, and/or the like. The term divalent non-aromatic condensed polycyclic group as utilized herein refers to a divalent group having substantially the same structure as the monovalent non-aromatic condensed polycyclic group described above.

[0687] The term monovalent non-aromatic hetero-condensed polycyclic group as utilized herein refers to a monovalent group (for example, having 1 to 60 carbon atoms) having two or more rings condensed to each other, further including, in addition to carbon atoms, at least one heteroatom, as ring-forming atoms, and having non-aromaticity in its entire molecular structure as a whole. Non-limiting examples of the monovalent non-aromatic hetero-condensed polycyclic group are a pyrrolyl group, a thiophenyl group, a furanyl group, an indolyl group, a benzoindolyl group, a naphthoindolyl group, an isoindolyl group, a benzoisoindolyl group, a naphthoisoindolyl group, a benzosilolyl group, a benzothiophenyl group, a benzofuranyl group, a carbazolyl group, a dibenzosilolyl group, a dibenzothiophenyl group, a dibenzofuranyl group, an azacarbazolyl group, an azafluorenyl group, an azadibenzosilolyl group, an azadibenzothiophenyl group, an azadibenzofuranyl group, a pyrazolyl group, an imidazolyl group, a triazolyl group, a tetrazolyl group, an oxazolyl group, an isoxazolyl group, a thiazolyl group, an isothiazolyl group, an oxadiazolyl group, a thiadiazolyl group, a benzopyrazolyl group, a benzimidazolyl group, a benzoxazolyl group, a benzothiazolyl group, a benzoxadiazolyl group, a benzothiadiazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, an imidazotriazinyl group, an imidazopyrazinyl group, an imidazopyridazinyl group, an indeno carbazolyl group, an indolocarbazolyl group, a benzofurocarbazolyl group, a benzothienocarbazolyl group, a benzosilolocarbazolyl group, a benzoindolocarbazolyl group, a benzocarbazolyl group, a benzonaphthofuranyl group, a benzonaphthothiophenyl group, a benzonaphthosilolyl group, a benzofurodibenzofuranyl group, a benzofurodibenzothiophenyl group, and a benzothienodibenzothiophenyl group. The term divalent non-aromatic condensed heteropolycyclic group as utilized herein refers to a divalent group having substantially the same structure as the monovalent non-aromatic condensed heteropolycyclic group.

[0688] The term C.sub.6-C.sub.60 aryloxy group as utilized herein indicates OA.sub.102 (wherein A.sub.102 is a C.sub.6-C.sub.60 aryl group), and the term C.sub.6-C.sub.60 arylthio group as utilized herein indicates SA.sub.103 (wherein A.sub.103 is a C.sub.6-C.sub.60 aryl group).

[0689] The term C.sub.7-C.sub.60 arylalkyl group as utilized herein refers to -A.sub.104A.sub.105 (wherein A.sub.104 is a C.sub.1-C.sub.54 alkylene group, and A.sub.105 is a C.sub.6-C.sub.59 aryl group), and the term C.sub.2-C.sub.60 heteroarylalkyl group as utilized herein refers to -A.sub.106A.sub.107 (wherein A.sub.106 is a C.sub.1-C.sub.59 alkylene group, and A.sub.107 is a C.sub.1-C.sub.59 heteroaryl group).

[0690] The term R.sub.10a as utilized herein may be: [0691] deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, or a nitro group; [0692] a C.sub.1-C.sub.60 alkyl group, a C.sub.2-C.sub.60 alkenyl group, a C.sub.2-C.sub.60 alkynyl group, or a C.sub.1-C.sub.60 alkoxy group, each unsubstituted or substituted with deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, a nitro group, a C.sub.3-C.sub.60 carbocyclic group, a C.sub.1-C.sub.60 heterocyclic group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.7-C.sub.60 arylalkyl group, a C.sub.2-C.sub.60 heteroarylalkyl group, Si(Q.sub.11)(Q.sub.12)(Q.sub.13), N(Q.sub.11)(Q.sub.12), B(Q.sub.11)(Q.sub.12), C(O)(Q.sub.11), S(O).sub.2(Q.sub.11), P(O)(Q.sub.11)(Q.sub.12), or any combination thereof; [0693] a C.sub.3-C.sub.60 carbocyclic group, a C.sub.1-C.sub.60 heterocyclic group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.7-C.sub.60 arylalkyl group, or a C.sub.2-C.sub.60 heteroarylalkyl group, each unsubstituted or substituted with deuterium, F, Cl, Br, I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.60 alkyl group, a C.sub.2-C.sub.60 alkenyl group, a C.sub.2-C.sub.60 alkynyl group, a C.sub.1-C.sub.60 alkoxy group, a C.sub.3-C.sub.60 carbocyclic group, a C.sub.1-C.sub.60 heterocyclic group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.7-C.sub.60 arylalkyl group, a C.sub.2-C.sub.60 heteroarylalkyl group, Si(Q.sub.21)(Q.sub.22)(Q.sub.23), N(Q.sub.21)(Q.sub.22), B(Q.sub.21)(Q.sub.22), C(O)(Q.sub.21), S(O).sub.2(Q.sub.21), P(O)(Q.sub.21)(Q.sub.22), or any combination thereof; or [0694] Si(Q.sub.31)(Q.sub.32)(Q.sub.33), N(Q.sub.31)(Q.sub.32), B(Q.sub.31)(Q.sub.32), C(O)(Q.sub.31), S(O).sub.2(Q.sub.31), or P(O)(Q.sub.31)(Q.sub.32).

[0695] Q.sub.1 to Q.sub.3, Q.sub.11 to Q.sub.13, Q.sub.21 to Q.sub.23 and Q.sub.31 to Q.sub.33 in the present disclosure may each independently be: hydrogen; deuterium; F; Cl; Br; I; a hydroxyl group; a cyano group; a nitro group; a C.sub.1-C.sub.60 alkyl group; a C.sub.2-C.sub.60 alkenyl group; a C.sub.2-C.sub.60 alkynyl group; a C.sub.1-C.sub.60 alkoxy group; a C.sub.3-C.sub.60 carbocyclic group or a C.sub.1-C.sub.60 heterocyclic group, each unsubstituted or substituted with deuterium, F, a cyano group, a C.sub.1-C.sub.60 alkyl group, a C.sub.1-C.sub.60 alkoxy group, a phenyl group, a biphenyl group, or any combination thereof; a C.sub.7-C.sub.60 aryl alkyl group; or a C.sub.2-C.sub.60 heteroaryl alkyl group.

[0696] The term heteroatom as utilized herein refers to any atom other than a carbon atom. Non-limiting examples of the heteroatom may include O, S, N, P, Si, B, Ge, Se, and any combination thereof.

[0697] The term third-row transition metal as utilized herein includes Hf, Ta, W, Re, Os, Ir, Pt, Au, and/or the like.

[0698] Ph as utilized herein refers to a phenyl group, Me as utilized herein refers to a methyl group, Et as utilized herein refers to an ethyl group, tert-Bu, Bu, or But as utilized herein refers to a tert-butyl group, and OMe as utilized herein refers to a methoxy group.

[0699] The term biphenyl group as utilized herein refers to a phenyl group substituted with a phenyl group. In some embodiments, the biphenyl group may be a substituted phenyl group having a C.sub.6-C.sub.60 aryl group as a substituent.

[0700] The term terphenyl group as utilized herein refers to a phenyl group substituted with a biphenyl group. In some embodiments, the terphenyl group may be a substituted phenyl group having, as a substituent, a C.sub.6-C.sub.60 aryl group substituted with a C.sub.6-C.sub.60 aryl group.

[0701] * and * as utilized herein, unless defined otherwise, each refer to a binding site to a neighboring atom in a corresponding formula or moiety.

[0702] In the present disclosure, the x-axis, y-axis, and z-axis are not limited to three axes in an orthogonal coordinate system, and may be interpreted in a broad sense including these axes. For example, the x-axis, y-axis, and z-axis may refer to those orthogonal to each other, or may refer to those in different directions that are not orthogonal to each other.

[0703] Hereinafter, compounds according to one or more embodiments and light-emitting devices according to one or more embodiments will be described in more detail with reference to the following Synthesis Examples and Examples. The wording B was utilized instead of A utilized in describing Synthesis Examples refers to that an identical molar equivalent of B was utilized in place of A.

EXAMPLES

Synthesis Example 1: Synthesis of Compound A-1

##STR00309## ##STR00310## ##STR00311##

(1) Synthesis of Intermediate IM-1-1

[0704] 2,4-dibromo-[1,2]azaborino[1,2-a][1,2]azaborin-3-amine (1 equiv.), Pd(PPh.sub.3).sub.4 (0.02 equiv.), K.sub.2CO.sub.3 (3 equiv.), and phenyl boronic acid (2 equiv.) were suspended in a mixed solution containing toluene and distilled water (at a volume ratio of 3:1, 0.125 M), and the resulting solution was heated and stirred under nitrogen at 100 C. for 6 hours. After cooling to room temperature, distilled water was added thereto, and an extraction process utilizing ethyl acetate was performed thereon to extract an organic layer, and the extracted organic layer was cleaned with sat. NaCl aqueous solution and dried with MgSO.sub.4. The resulting product was subjected to column chromatography (100% hexane to 1% methylene chloride (MC)/hexane as an eluent) to obtain Intermediate IM-1-1 (yield: 75%).

(2) Synthesis of Intermediate IM-2-1

[0705] Intermediate IM-1-1 (1 equiv.), 1-Iodo-2-nitrobenzene (1.1 equiv.), tris(dibenzylideneacetone)dipalladium(0) (Pd.sub.2(dba).sub.3) (0.02 equiv.), 2-dicyclohexylphosphino-2,6-dimethoxybiphenyl (Sphos) (0.04 equiv.), and NaO.sup.tBu (1.6 equiv.) were suspended in a toluene solvent, and the resulting solution was heated at 120 C. for 12 hours in a nitrogen atmosphere. After cooling to room temperature, distilled water was added thereto, and an extraction process utilizing ethyl acetate was performed thereon to extract an organic layer, and the extracted organic layer was cleaned with sat. NaCl aqueous solution and dried with MgSO.sub.4. The resulting product was subjected to column chromatography (5% (volume ratio) ethyl acetate (EA)/hexane as an eluent) to obtain Intermediate IM-2-1 (yield: 78%).

(3) Synthesis of Intermediate IM-3-1

[0706] Intermediate IM-2-1 (1 equiv.) was dissolved in ethanol (0.1 M) and added dropwise to 37% HCl (1% volume ratio). After Sn (1 equiv.) was added to the reaction mixture and the temperature was raised, the resulting reaction mixture was stirred at 80 C. for 10 hours. After completion of the reaction, the reaction product was cooled to room temperature and neutralized with 1 N NaOH aqueous solution. An extraction process utilizing MC and distilled water was performed thereon, followed by drying with MgSO.sub.4. The dried compound was utilized in the next reaction without further purification.

(4) Synthesis of Intermediate IM-4-1

[0707] Intermediate IM-4-1 was synthesized in substantially the same manner as in Synthesis of Intermediate IM-2-1, except that Intermediate IM-3-1 was utilized instead of Intermediate IM-1-1 and 2-(3-bromophenoxy)-9-(4-(tert-butyl)pyridin-2-yl)-9H-carbazole was utilized instead of 1-Iodo-2-nitrobenzene (yield: 71%).

(5) Synthesis of Intermediate IM-5-1

[0708] Intermediate IM-4-1 (1 equiv.) was dissolved in triethyl orthoformate (50 equiv.) and added dropwise to 12 N HCl (1.2 equiv.). The temperature was raised to 80 C., and the reaction mixture was stirred for 12 hours. After completion of the reaction, the solvent was removed under reduced pressure, and an extraction process utilizing ethyl acetate and distilled water was performed on the reaction product. After drying with MgSO.sub.4, the resulting solid was purified by column chromatography (5% MeOH/MC as an eluent) to obtain Intermediate IM-5-1 (yield: 82%).

(6) Synthesis of Intermediate IM-6-1

[0709] Intermediate IM-5-1 (1 equiv.) and NH.sub.4PF.sub.6 (3 equiv.) were dissolved in methanol (0.2 M), and the mixed solution was stirred at room temperature for 24 hours. After completion of the reaction, the resulting solid was filtered and washed with ether several times. After drying at room temperature, Intermediate IM-6-1 was obtained (yield: 80%).

(7) Synthesis of Compound A-1

[0710] Intermediate IM-6-1 (1 equiv.), (1,5-cyclooctadiene) platinum (II) dichloride (Pt(COD)Cl.sub.2) (1.2 equiv.), and NaOAc (3 equiv.) were mixed with 1,4-dioxane (0.05 M). The reaction mixture was stirred at 110 C. for 72 hours. After completion of the reaction, the solvent was removed under reduced pressure, and an extraction process utilizing ethyl acetate and NaCl solution was performed on the reaction product. After drying with MgSO.sub.4, the resulting solid was purified by column chromatography (5% MeOH/MC as an eluent) to obtain Compound A-1 (yield: 78%).

Synthesis Example 2: Synthesis of Compound B-1

##STR00312## ##STR00313## ##STR00314##

(1) Synthesis of Intermediate IM-1-2

[0711] Intermediate IM-1-2 was obtained in substantially the same manner as in Synthesis of Intermediate IM-1-1, except that 1,3-dibromo-[1,2]azaborino[1,2-a][1,2]azaborin-2-amine was utilized instead of 2,4-dibromo-[1,2]azaborino[1,2-a][1,2]azaborin-3-amine (yield: 77%).

(2) Synthesis of Intermediate IM-2-2

[0712] Intermediate IM-2-2 was obtained in substantially the same manner as in Synthesis of Intermediate IM-2-1, except that Intermediate IM-1-2 was utilized instead of Intermediate IM-1-1 (yield: 81%).

(3) Synthesis of Intermediate IM-3-2

[0713] Intermediate IM-3-2 was obtained in substantially the same manner as in Synthesis of Intermediate IM-3-1, except that Intermediate IM-2-2 was utilized instead of Intermediate IM-2-1.

(4) Synthesis of Intermediate IM-4-2

[0714] Intermediate IM-4-2 was obtained in substantially the same manner as in Synthesis of Intermediate IM-4-1, except that Intermediate IM-3-2 was utilized instead of Intermediate IM-3-1 (yield: 72%).

(5) Synthesis of Intermediate IM-5-2

[0715] Intermediate IM-5-2 was obtained in substantially the same manner as in Synthesis of Intermediate IM-5-1, except that Intermediate IM-4-2 was utilized instead of Intermediate IM-4-1 (yield: 74%).

(6) Synthesis of Intermediate IM-6-2

[0716] Intermediate IM-6-2 was obtained in substantially the same manner as in Synthesis of Intermediate IM-6-1, except that Intermediate IM-5-2 was utilized instead of Intermediate IM-5-1 (yield: 79%).

(7) Synthesis of Compound B-1

[0717] Compound B-1 was obtained in substantially the same manner as in Synthesis of Compound A-1, except that Intermediate IM-6-2 was utilized instead of Intermediate IM-6-1 (yield: 70%).

Synthesis Example 3: Synthesis of Compound C-1

##STR00315## ##STR00316## ##STR00317##

(1) Synthesis of Intermediate IM-1-3

[0718] Intermediate IM-1-3 was obtained in substantially the same manner as in Synthesis of Intermediate IM-1-1, except that 3,7-dibromo-[1,2]azaborino[1,2-a][1,2]azaborin-4-amine was utilized instead of 2,4-dibromo-[1,2]azaborino[1,2-a][1,2]azaborin-3-amine (yield: 70%).

(2) Synthesis of Intermediate IM-2-3

[0719] Intermediate IM-2-3 was obtained in substantially the same manner as in Synthesis of Intermediate IM-2-1, except that Intermediate IM-1-3 was utilized instead of Intermediate IM-1-1 (yield: 68%).

(3) Synthesis of Intermediate IM-3-3

[0720] Intermediate IM-3-3 was obtained in substantially the same manner as in Synthesis of Intermediate IM-3-1, except that Intermediate IM-2-3 was utilized instead of Intermediate IM-2-1.

(4) Synthesis of Intermediate IM-4-3

[0721] Intermediate IM-4-3 was obtained in substantially the same manner as in Synthesis of Intermediate IM-4-1, except that Intermediate IM-3-3 was utilized instead of Intermediate IM-3-1 (yield: 62%).

(5) Synthesis of Intermediate IM-5-3

[0722] Intermediate IM-5-3 was obtained in substantially the same manner as in Synthesis of Intermediate IM-5-1, except that Intermediate IM-4-3 was utilized instead of Intermediate IM-4-1 (yield: 76%).

(6) Synthesis of Intermediate IM-6-3

[0723] Intermediate IM-6-3 was obtained in substantially the same manner as in Synthesis of Intermediate IM-6-1, except that Intermediate IM-5-3 was utilized instead of Intermediate IM-5-1 (yield: 78%).

(7) Synthesis of Compound C-1

[0724] Compound C-1 was obtained in substantially the same manner as in Synthesis of Compound A-1, except that Intermediate IM-6-3 was utilized instead of Intermediate IM-6-1 (yield: 80%).

Synthesis Example 4: Synthesis of Compound D-1

##STR00318## ##STR00319## ##STR00320##

(1) Synthesis of Intermediate IM-1-4

[0725] Intermediate IM-1-4 was obtained in substantially the same manner as in Synthesis of Intermediate IM-1-1, except that 2,8-dibromo-[1,2]azaborino[1,2-a][1,2]azaborin-1-amine was utilized instead of 2,4-dibromo-[1,2]azaborino[1,2-a][1,2]azaborin-3-amine (yield: 81%).

(2) Synthesis of Intermediate IM-2-4

[0726] Intermediate IM-2-4 was obtained in substantially the same manner as in Synthesis of Intermediate IM-2-1, except that Intermediate IM-1-4 was utilized instead of Intermediate IM-1-1 (yield: 85%).

(3) Synthesis of Intermediate IM-3-4

[0727] Intermediate IM-3-4 was obtained in substantially the same manner as in Synthesis of Intermediate IM-3-1, except that Intermediate IM-2-4 was utilized instead of Intermediate IM-2-1.

(4) Synthesis of Intermediate IM-4-4

[0728] Intermediate IM-4-4 was obtained in substantially the same manner as in Synthesis of Intermediate IM-4-1, except that Intermediate IM-3-4 was utilized instead of Intermediate IM-3-1 (yield: 79%).

(5) Synthesis of Intermediate IM-5-4

[0729] Intermediate IM-5-4 was obtained in substantially the same manner as in Synthesis of Intermediate IM-5-1, except that Intermediate IM-4-4 was utilized instead of Intermediate IM-4-1 (yield: 83%).

(6) Synthesis of Intermediate IM-6-4

[0730] Intermediate IM-6-4 was obtained in substantially the same manner as in Synthesis of Intermediate IM-6-1, except that Intermediate IM-5-4 was utilized instead of Intermediate IM-5-1 (yield: 80%).

(7) Synthesis of Compound D-1

[0731] Compound D-1 was obtained in substantially the same manner as in Synthesis of Compound A-1, except that Intermediate IM-6-4 was utilized instead of Intermediate IM-6-1 (yield: 78%).

[0732] .sup.1H nuclear magnetic resonance spectroscopy (NMR) and mass spectroscopy/fast atom bombardment (MS/FAB) of the compounds synthesized according to Synthesis Examples are shown in Table 1. Synthesis methods of compounds other than the compounds synthesized in Synthesis Examples above may be easily recognized by those skilled in the art by referring to the synthesis paths and source materials.

TABLE-US-00001 TABLE 1 Compound MS/FAB No. .sup.1H NMR (CDCl.sub.3, 400 MHz) found calc. A-1 8.74 (d, 1H), 8.39 (d, 1H), 8.19 (d, 1H), 7.50-7.75 980.30 980.84 (m, 2H), 7.35-7.60 (m, 10H), 7.15-7.28 (m, 5H), 7.08 (d, 1H), 6.88-6.95 (m, 3H), 6.65-6.75 (m, 4H), 6.19 (d, 1H), 5.6 (s, 1H), 5.0 (s, 1H), 1.32 (s, 9H) B-1 8.73 (d, 1H), 8.38 (d, 1H), 8.17 (d, 1H), 7.58 (d, 1H), 980.30 980.84 7.15-7.40 (m, 9H), 7.15-7.25 (m, 6H), 7.03(d, 1H), 6.82-6.95 (m, 3H), 6.65-6.77 (m, 5H), 6.19 (d, 1H), 5.1 (d, 1H), 1.32 (s, 9H) C-1 8.74 (d, 1H), 8.39 (d, 1H), 8.17 (d, 1H), 7.56 (d, 1H), 980.30 980.84 7.45-7.56 (m, 3H), 7.35-7.42 (m, 8H), 7.15-7.22 (m, 6H), 7.01 (d, 1H), 6.82-6.91 (m, 2H), 6.64-6.77 (m, 5H), 5.2 (s, 1H), 5.1 (s, 1H), 1.32 (s, 9H) D-1 8.73 (d, 1H), 8.38 (d, 1H), 8.19 (d, 1H), 7.57 (d, 1H), 980.30 980.84 7.50 (m, 1H), 7.35-7.42 (m, 8H), 7.15-7.22 (m, 6H), 7.02 (d, 1H), 6.82-6.92 (m, 2H), 6.64-6.78 (m, 4H), 6.37 (s, 1H), 6.35 (s, 1H), 5.45-5.62 (m, 3H), 1.32 (s, 9H)

Evaluation Example 1

[0733] For Compounds A-1, B-1, C-1, and D-1 described above and Compound CE2 below, the HOMO energy level (eV), LUMO energy level (eV), T1 energy level (nm), Huang-Rhys factors (HRF) (cm.sup.1), dipole moment (Debye), and existence ratio (%) in triplet metal-to-ligand charge transfer state (.sup.3MLCT) were evaluated by utilizing the density functional theory (DFT) method of the Gaussian program, which is structure-optimized at the B3LYP/6-31G(d,p) level, and the results are shown in Table 2.

TABLE-US-00002 TABLE 2 Compound HOMO LUMO T1 (nm) HRF Dipole .sup.3MLCT No. (eV) (eV) (revised) (cm.sup.1) (debye) (%) A-1 4.94 1.72 457.94 717.40 6.90 10.13 B-1 4.87 1.88 480.01 641.40 8.34 9.47 C-1 4.94 1.87 474.89 684.40 6.63 12.61 D-1 4.78 1.92 471.19 629.90 9.71 6.86 CE2 4.77 1.66 486.02 782.00 7.71 8.87 A-1 [00321]B-1 [00322]C-1 [00323]D-1 [00324]CE2 [00325]

Example 1

[0734] As an anode, a glass substrate on which a Corning 15 /cm.sup.2 (1,200 ) ITO was deposited was cut to a size of 50 mm50 mm0.7 mm, sonicated with isopropyl alcohol and pure water each for 5 minutes, and then cleaned by exposure to ultraviolet rays and ozone for 30 minutes. The ITO glass substrate was then mounted on a vacuum deposition apparatus.

[0735] 2-TNATA was vacuum-deposited on the ITO glass substrate to form a hole injection layer having a thickness of 600 , and 4,4-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (hereinafter, referred as NPB) was vacuum-deposited on the hole injection layer to form a hole transport layer having a thickness of 300 .

[0736] Compounds HTH29 and ETH100 as hosts and Compound A-1 as a dopant were co-deposited at a weight ratio of 60:30:10 (HTH29:ETH100:A-1) on the hole transport layer to form an emission layer having a thickness of 300 .

[0737] Diphenyl(4-(triphenylsilyl)phenyl)-phosphine oxide (TSPO1) was vacuum-deposited on the emission layer to form a hole blocking layer having a thickness of 50 , and then Alq.sub.3 was deposited on the hole blocking layer to form an electron transport layer having a thickness of 300 . A halogenated alkali metal, LiF, was deposited on the electron transport layer to form an electron injection layer having a thickness of 10 , and Al was vacuum-deposited on the electron injection layer to form a LiF/Al cathode electrode having a thickness of 3,000 , thereby completing the manufacture of a light-emitting device.

##STR00326##

Examples 2 to 4 and Comparative Examples 1 to 3

[0738] Light-emitting devices were each manufactured in substantially the same manner as in Example 1, except that compounds shown in Table 3 were each utilized instead of Compound 1 as a dopant in forming an emission layer.

Evaluation Example 2

[0739] The driving voltage (V) at luminance of 1,000 cd/m.sup.2, efficiency (cd/A), color conversion efficiency (cd/A/y), maximum emission wavelength (nm), and device lifespan (h) of the light-emitting devices of Examples 1 to 4 and Comparative Examples 1 to 4 were each measured by utilizing a Keithley SMU 236 meter and a luminance meter PR650, and the results are shown in Table 3. In Table 3, the lifespan ratio (T.sub.95, reference ratio) refers to the time (h) required for the luminance to reach 95% of the initial luminance of each of the light-emitting devices of Examples and Comparative Examples above, expressed as a percentage (%) with respect to the lifespan of the light-emitting device of Comparative Example 1 which is set to be 100.

TABLE-US-00003 TABLE 3 Device lifespan Color Maximum ratio Dopant in Driving conversion emission (T.sub.95, emission Luminance voltage Efficiency efficiency wavelength reference layer (cd/m.sup.2) (V) (cd/A) (cd/A/y) (nm) ratio, %) Example 1 A-1 1000 4.8 22.5 127.1 463 346.7 Example 2 B-1 1000 4.6 23.3 127.8 463 378.2 Example 3 C-1 1000 4.6 21.4 137.1 461 295.6 Example 4 D-1 1000 4.7 23.6 138.1 461 300 Comparative CE1 1000 4.7 22.9 118.5 463 100 Example 1 (reference) Comparative CE2 1000 4.3 26.8 92.4 464 8.9 Example 2 Comparative CE3 1000 4.7 24.6 120.6 463 77.8 Example 3 A-1 [00327]B-1 [00328]C-1 [00329]D-1 [00330]CE1 [00331]CE2 [00332]CE3 [00333]

[0740] Referring to Table 3, it was confirmed that the light-emitting devices according to Examples 1 to 4 each had excellent or suitable driving voltage, luminescence efficiency, and lifespan characteristics compared to those of the light-emitting devices according to Comparative Examples 1 to 3.

[0741] According to the one or more embodiments, utilization of the organometallic compound of the present disclosure may lead to the manufacture of a light-emitting device, which has reduced driving voltage, improved color purity and efficiency, and long lifespan, and a high-quality electronic apparatus including the light-emitting device.

[0742] In the present disclosure, it will be understood that the terms comprise(s), include(s), or have/has specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

[0743] Throughout the present disclosure, when a component such as a layer, a film, a region, or a plate is mentioned to be placed on another component, it will be understood that it may be directly on another component or that another component may be interposed therebetween. In some embodiments, directly on may refer to that there are no additional layers, films, regions, plates, etc., between a layer, a film, a region, a plate, etc. and the other part. For example, directly on may refer to two layers or two members are disposed without utilizing an additional member such as an adhesive member therebetween.

[0744] In the present disclosure, although the terms first, second, etc., may be utilized herein to describe one or more elements, components, regions, and/or layers, these elements, components, regions, and/or layers should not be limited by these terms. These terms are only utilized to distinguish one component from another component.

[0745] As utilized herein, the singular forms a, an, one, and the are intended to include the plural forms as well, unless the context clearly indicates otherwise. Further, the use of may when describing embodiments of the present disclosure refers to one or more embodiments of the present disclosure.

[0746] As utilized herein, the terms substantially, about, or similar terms are used as terms of approximation and not as terms of degree, and are intended to account for the inherent deviations in measured or calculated values that would be recognized by those of ordinary skill in the art. About as used herein, is inclusive of the stated value and means within an acceptable range of deviation for the particular value as determined by one of ordinary skill in the art, considering the measurement in question and the error associated with measurement of the particular quantity (i.e., the limitations of the measurement system). For example, about may mean within one or more standard deviations, or within 30%, 20%, 10%, 5% of the stated value.

[0747] Any numerical range recited herein is intended to include all sub-ranges of the same numerical precision subsumed within the recited range. For example, a range of 1.0 to 10.0 is intended to include all subranges between (and including) the recited minimum value of 1.0 and the recited maximum value of 10.0, that is, having a minimum value equal to or greater than 1.0 and a maximum value equal to or less than 10.0, such as, for example, 2.4 to 7.6. Any maximum numerical limitation recited herein is intended to include all lower numerical limitations subsumed therein and any minimum numerical limitation recited in this specification is intended to include all higher numerical limitations subsumed therein. Accordingly, Applicant reserves the right to amend this specification, including the claims, to expressly recite any sub-range subsumed within the ranges expressly recited herein.

[0748] It should be understood that embodiments described herein should be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects within each embodiment should typically be considered as available for other similar features or aspects in other embodiments. While one or more embodiments have been described with reference to the drawings, it will be understood by those of ordinary skill in the art that one or more suitable changes in form and details may be made therein without departing from the spirit and scope as defined by the following claims and equivalents thereof.