Composition and organic light-emitting device including the same

Abstract

A composition including a first compound including a compound represented by Formula 1, a second compound including a compound represented by Formula 2, and a third compound including a compound represented by Formula 3, and an organic light-emitting device including the composition: ##STR00001## wherein the description of Formulae 1 to 3 are the same as described in the specification.

Claims

1. A composition comprising: a first compound, a second compound, and a third compound, wherein the first compound comprises a compound represented by Formula 1, the second compound comprises a compound represented by Formula 2, and the third compound comprises a compound represented by Formula 3: ##STR00195## wherein Y.sub.2 in Formula 1 is C, a group represented by ##STR00196## in Formula 1 is a group represented by Formula A(1): ##STR00197## wherein, in Formula A(1), R.sub.9 and R.sub.11 are each independently a C.sub.1-C.sub.20 alkyl group, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.2-C.sub.10 heterocycloalkyl group, or a phenyl group, each unsubstituted or substituted with deuterium, a C.sub.1-C.sub.20 alkyl group, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.2-C.sub.10 heterocycloalkyl group, a phenyl group, or any combination thereof, and R.sub.10 and R.sub.12 are each independently hydrogen or deuterium, *′indicates a binding site to Ir in Formula 1, and *″ indicates a binding site to a neighboring atom in Formula 1, Ar.sub.1, Ar.sub.2, and Ar.sub.n in Formulae 2 and 3 are each independently a C.sub.5-C.sub.60 carbocyclic group which is unsubstituted or substituted with at least one R.sub.61 or a C.sub.1-C.sub.60 heterocyclic group which is unsubstituted or substituted with at least one R.sub.61, Ar.sub.5 and A.sub.12 in Formulae 2 and 3 are each independently a single bond, a C.sub.5-C.sub.60 carbocyclic group which is unsubstituted or substituted with at least one R.sub.65, or a C.sub.1-C.sub.60 heterocyclic group which is unsubstituted or substituted with at least one R.sub.65, or does not exist, n in Formula 2 is 1, 2, or 3, and when n is 1, Ar.sub.5 does not exist, p in Formula 3 is 1, 2, or 3, and when p is 1, Ar.sub.12 does not exist, a1 and a2 in Formula 2 are each independently an integer from 0 to 5, and the sum of a1 and a2 is 1 or more, ring CY.sub.2 and ring CY.sub.3 in Formula 2 are each independently a C.sub.5-C.sub.60 carbocyclic group or a C.sub.1-C.sub.60 heterocyclic group, and ring CY.sub.2 and ring CY.sub.3 are optionally linked to each other with a C.sub.5-C.sub.60 carbocyclic group which is unsubstituted or substituted with at least one R.sub.66 or a C.sub.1-C.sub.60 heterocyclic group which is unsubstituted or substituted with at least one R.sub.66 therebetween, Het1 in Formula 3 is a π electron-depleted nitrogen-containing C.sub.1-C.sub.60 cyclic group, a11 and m in Formula 3 are each independently an integer from 1 to 10, R.sub.1 to R.sub.8, A.sub.1 to A.sub.7, R.sub.20, R.sub.30, R.sub.61, R.sub.65, R.sub.66, R.sub.70, and R.sub.80 in Formulae 1 to 3 are each independently hydrogen, deuterium, —F, —Cl, —Br, —I, —SF.sub.5, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazino group, a hydrazono group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a substituted or unsubstituted C.sub.1-C.sub.60 alkyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkenyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkynyl group, a substituted or unsubstituted C.sub.1-C.sub.60 alkoxy group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.2-C.sub.10 heterocycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.2-C.sub.10 heterocycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryloxy group, a substituted or unsubstituted C.sub.6-C.sub.60 arylthio group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —N(Q.sub.1)(Q.sub.2), —Si(Q.sub.3)(Q.sub.4)(Qs), —Ge(Q.sub.3)(Q.sub.4)(Qs), —B(Q.sub.6)(Q.sub.7), —P(═O)(Qs)(Q.sub.9), or —P(Qs)(Q.sub.9), provided that at least one of R.sub.1 to Rs is a fluoro group (—F), b2, b3, b7, and b8 in Formulae 2 and 3 are each independently an integer from 0 to 20, when b2 is 2 or more, two or more R.sub.20(s) are identical to or different from each other, when b3 is 2 or more, two or more R.sub.30(s) are identical to or different from each other, when b7 is 2 or more, two or more R.sub.70(s) are identical to or different from each other, and when b8 is 2 or more, two or more R.sub.80(s) are identical to or different from each other, two or more of R.sub.1 to Rs in Formula 1 are optionally linked to form a C.sub.5-C.sub.60 carbocyclic group which is unsubstituted or substituted with at least one Ria or a C.sub.1-C.sub.0 heterocyclic group which is unsubstituted or substituted with at least one R.sub.1a, two or more of A.sub.1 to A.sub.7 in Formula 1 are optionally linked to form a C.sub.5-C.sub.60 carbocyclic group which is unsubstituted or substituted with at least one Ria or a C.sub.1-C.sub.0 heterocyclic group which is unsubstituted or substituted with at least one R.sub.1a, two or more of ring CY.sub.2, ring CY.sub.3, R.sub.20, and R.sub.30 in Formula 2 are optionally linked to form a C.sub.5-C.sub.60 carbocyclic group which is unsubstituted or substituted with at least one Ria or a C.sub.1-C.sub.60 heterocyclic group which is unsubstituted or substituted with at least one R.sub.1a, R.sub.1a is understood by referring to the description of A.sub.7 provided above, and a substituent of the substituted C.sub.1-C.sub.60 alkyl group, the substituted C.sub.2-C.sub.60 alkenyl group, the substituted C.sub.2-C.sub.60 alkynyl group, the substituted C.sub.1-C.sub.60 alkoxy group, the substituted C.sub.3-C.sub.10 cycloalkyl group, the substituted C.sub.2-C.sub.10 heterocycloalkyl group, the substituted C.sub.3-C.sub.10 cycloalkenyl group, the substituted C.sub.2-C.sub.10 heterocycloalkenyl group, the substituted C.sub.6-C.sub.60 aryl group, the substituted C.sub.6-C.sub.60 aryloxy group, the substituted C.sub.6-C.sub.60 arylthio group, the substituted C.sub.1-C.sub.60 heteroaryl group, the substituted monovalent non-aromatic condensed polycyclic group, and the substituted monovalent non-aromatic condensed heteropolycyclic group is: 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, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, 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 C.sub.1-C.sub.60 alkoxy 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 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, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.2-C.sub.10 heterocycloalkyl group, a C.sub.3-C.sub.10 cycloalkenyl group, a C.sub.2-C.sub.10 heterocycloalkenyl group, a C.sub.6-C.sub.60 aryl group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.1-C.sub.60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —N(Q.sub.11)(Q.sub.12), —Si(Q.sub.13)(Q.sub.14)(Q.sub.15), —Ge(Q.sub.13)(Q.sub.14)(Q.sub.15), —B(Q.sub.16)(Q.sub.17), —P(═O)(Q.sub.18)(Q.sub.19), —P(Q.sub.18)(Q.sub.19), or any combination thereof; a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.2-C.sub.10 heterocycloalkyl group, a C.sub.3-C.sub.10 cycloalkenyl group, a C.sub.2-C.sub.10 heterocycloalkenyl group, a C.sub.6-C.sub.60 aryl group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.1-C.sub.60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, or a monovalent non-aromatic condensed heteropolycyclic 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, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, 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.10 cycloalkyl group, a C.sub.2-C.sub.10 heterocycloalkyl group, a C.sub.3-C.sub.10 cycloalkenyl group, a C.sub.2-C.sub.10 heterocycloalkenyl group, a C.sub.6-C.sub.60 aryl group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.1-C.sub.60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —N(Q.sub.21)(Q.sub.22), —Si(Q.sub.23)(Q.sub.24)(Q.sub.25), —Ge(Q.sub.23)(Q.sub.24)(Q.sub.25), —B(Q.sub.26)(Q.sub.27), —P(═O)(Q.sub.28)(Q.sub.29), —P(Q.sub.28)(Q.sub.29), or any combination thereof; —N(Q.sub.31)(Q.sub.32), —Si(Q.sub.33)(Q.sub.34)(Q.sub.35), —Ge(Q.sub.33)(Q.sub.34)(Q.sub.35), —B(Q.sub.36)(Q.sub.37), —P(═O)(Q.sub.38)(Q.sub.39),or —P(Q.sub.38)(Q.sub.39); or any combination thereof, wherein Q.sub.1 to Q.sub.9, Q.sub.11 to Q.sub.19, Q.sub.21 to Q.sub.29, and Q.sub.31 to Q.sub.39 are each independently hydrogen; deuterium; —F; —C.sub.1; —Br; —I; a hydroxyl group; a cyano group; a nitro group; an amidino group; a hydrazine group; a hydrazone group; a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof; a phosphoric acid group or a salt thereof; a C.sub.1-C.sub.60 alkyl group, unsubstituted or substituted with deuterium, a C.sub.1-C.sub.60 alkyl group, a C.sub.6-C.sub.60 aryl group, or any combination thereof; 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.10 cycloalkyl group; a C.sub.2-C.sub.10 heterocycloalkyl group; a C.sub.3-C.sub.10 cycloalkenyl group; a C.sub.2-C.sub.10 heterocycloalkenyl group; a C.sub.6-C.sub.60 aryl group, unsubstituted or substituted with deuterium, a C.sub.1-C.sub.0 alkyl group, a C.sub.6-C.sub.60 aryl group, or any combination thereof, a C.sub.6-C.sub.60 aryloxy group; a C.sub.6-C.sub.60 arylthio group; a C.sub.1-C.sub.60 heteroaryl group; a monovalent non-aromatic condensed polycyclic group; or a monovalent non-aromatic condensed heteropolycyclic group.

2. The composition of claim 1, wherein R.sub.1 to R.sub.8 and A.sub.1 to A.sub.7 are each independently: hydrogen, deuterium, or —F; a C.sub.1-C.sub.20 alkyl group, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.2-C.sub.10 heterocycloalkyl group, or a phenyl group, each unsubstituted or substituted with deuterium, —F, a C.sub.1-C.sub.20 alkyl group, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.2-C.sub.10 heterocycloalkyl group, a phenyl group, or any combination thereof.

3. The composition of claim 1, wherein at least one of A.sub.1 to A.sub.6 in Formula 1 is an unsubstituted or substituted C.sub.2-C.sub.60 alkyl group, an unsubstituted or substituted C.sub.3-C.sub.10 cycloalkyl group, or an unsubstituted or substituted C.sub.2-C.sub.10 heterocycloalkyl group.

4. The composition of claim 1, wherein A.sub.1 to A.sub.6 are each independently an unsubstituted or substituted C.sub.1-C.sub.60 alkyl group, an unsubstituted or substituted C.sub.3-C.sub.10 cycloalkyl group, or an unsubstituted or substituted C.sub.2-C.sub.10 heterocycloalkyl group.

5. The composition of claim 1, wherein a group represented by ##STR00198## in Formula 1 is a group represented by one of Formulae CY1 to CY108: ##STR00199## ##STR00200## ##STR00201## ##STR00202## ##STR00203## ##STR00204## ##STR00205## ##STR00206## ##STR00207## ##STR00208## ##STR00209## ##STR00210## ##STR00211## ##STR00212## ##STR00213## ##STR00214## ##STR00215## ##STR00216## ##STR00217## wherein, in Formulae CY1 to CY108, T.sub.2 to T.sub.8 are each a fluoro group (—F), each of R.sub.2 to R.sub.8 and R.sub.1a are the same as described in claim 1, provided that R.sub.2 to R.sub.8 are not hydrogen, indicates a binding site to Ir in Formula 1, and *″ indicates a binding site to a neighboring atom in Formula 1.

6. The composition of claim 1, wherein Ar.sub.1, Ar.sub.2, and Ar.sub.11 in Formulae 2 and 3 are each independently a group derived from i) a first ring unsubstituted or substituted with at least one R.sub.61, ii) a second ring unsubstituted or substituted with at least one R.sub.61, iii) a condensed cyclic group in which two or more first rings are condensed with each other, unsubstituted or substituted with at least one R.sub.61, iv) a condensed cyclic group in which two or more second rings are condensed with each other, unsubstituted or substituted with at least one R.sub.61, or v) a condensed cyclic group in which at least one first ring and at least one second ring are condensed with each other, unsubstituted or substituted with at least one R.sub.61, Ar.sub.5 and Ar.sub.12 in Formulae 2 and 3 are each independently a single bond or a group derived from i) a first ring unsubstituted or substituted with at least one R.sub.65, ii) a second ring unsubstituted or substituted with at least one R.sub.65, iii) a condensed cyclic group in which two or more first rings are condensed with each other, unsubstituted or substituted with at least one R.sub.65, iv) a condensed cyclic group in which two or more second rings are condensed with each other, unsubstituted or substituted with at least one R.sub.65, or v) a condensed cyclic group in which at least one first ring and at least one second ring are condensed with each other, unsubstituted or substituted with at least one R.sub.65, or does not exist, ring CY.sub.2 and ring CY.sub.3 in Formula 2 are each independently i) a first ring, ii) a second ring, iii) a condensed cyclic group in which two or more first rings are condensed with each other, iv) a condensed cyclic group in which two or more second rings are condensed with each other, or v) a condensed cyclic group in which at least one first ring and at least one second ring are condensed with each other, Het1 in Formula 3 is a group derived from i) a first ring, ii) a condensed cyclic group in which two or more first rings are condensed with each other, or iii) a condensed cyclic group in which at least one first ring and at least one second ring are condensed with each other, the first ring is an imidazole group, a pyrazole group, a thiazole group, an isothiazole group, an oxazole group, an isoxazole group, a pyridine group, a pyrazine group, a pyridazine group, a pyrimidine group, a triazole group, a tetrazole group, an oxadiazole group, a triazine group, or a thiadiazole group, and the second ring is a benzene group, a cyclopentadiene group, a pyrrole group, a furan group, a thiophene group, or a silole group.

7. The composition of claim 1, wherein Ar.sub.1, Ar.sub.2, and Ar.sub.11 in Formulae 2 and 3 are each independently a π electron-rich C.sub.3-C.sub.60 cyclic group unsubstituted or substituted with at least one R.sub.6i, Ar.sub.5 and Ar.sub.12 in Formulae 2 and 3 are each independently a single bond or a R electron-rich C.sub.3-C.sub.60 cyclic group unsubstituted or substituted with at least one R.sub.65, or do not exist, and ring CY.sub.2 and ring CY.sub.3 in Formula 2 are each independently a πelectron-rich C.sub.3-C.sub.60 cyclic group.

8. The composition of claim 1, wherein a group represented by ##STR00218## in Formula 2 is represented by one of Formulae 2-1 to 2-93: ##STR00219## ##STR00220## ##STR00221## ##STR00222## ##STR00223## ##STR00224## ##STR00225## wherein, in Formulae 2-1 to 2-93, X.sub.1 is O, S, N(R.sub.31), C(R.sub.31)(R.sub.32>, or Si(R.sub.31)(R.sub.32), X.sub.2 is O, S, N(R.sub.33), C(R.sub.33)(R.sub.34), or Si(R.sub.33)(R.sub.34), R.sub.31 to R.sub.34 are the same as described in connection with R.sub.30 in claim 1, and indicates a binding site to Ar.sub.1 or Ar.sub.2 in Formula 2.

9. The composition of claim 1, wherein Het1 in Formula 3 is a group derived from one of Formulae 3-1 to 3-40: ##STR00226## ##STR00227## ##STR00228## ##STR00229##

10. The composition of claim 1, wherein a11 and m in Formula 3 are each independently an integer from 1to 3.

11. The composition of claim 1, wherein R.sub.20, R.sub.30, R.sub.61, R.sub.65, R.sub.66, R.sub.70 and R.sub.80 in Formulae 2 and 3 are each independently: hydrogen or deuterium; a C.sub.1-C.sub.20 alkyl group or a C.sub.1-C.sub.20 alkoxy group, each unsubstituted or substituted with deuterium, a phenyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a triphenylenyl group, a fluorenyl group, a di(C.sub.1-C.sub.10 alkyl)fluorenyl group, a di(C.sub.6-C.sub.60 aryl)fluorenyl group, a dibenzosilolyl group, a di(C.sub.1-C.sub.10 alkyl)dibenzosilolyl group, a di(C.sub.6-C.sub.60 aryl)dibenzosilolyl group, a carbazolyl group, a (C.sub.1-C.sub.10 alkyl)carbazolyl group, a (C.sub.6-C.sub.60 aryl)carbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a biphenyl group, a terphenyl group, -N(Q.sub.31)(Q.sub.32), or any combination thereof, a π electron-rich C.sub.3-C.sub.60 cyclic group, unsubstituted or substituted with deuterium, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a triphenylenyl group, a fluorenyl group, a di(C.sub.1-C.sub.10 alkyl)fluorenyl group, a di(C.sub.6-C.sub.60 aryl)fluorenyl group, a dibenzosilolyl group, a di(C.sub.1-C.sub.10 alkyl)dibenzosilolyl group, a di(C.sub.6-C.sub.60 aryl)dibenzosilolyl group, a carbazolyl group, a (C.sub.1-C.sub.10 alkyl)carbazolyl group, a (C.sub.6-C.sub.60 aryl)carbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a biphenyl group, a terphenyl group, -N(Q.sub.31)(Q.sub.32), or any combination thereof, or N(Q.sub.1)(Q.sub.2).

12. The composition of claim 1, wherein the second compound comprises at least one of Compounds H1-1 to H1-72, and the third compound comprises at least one of Compounds H2-1 to H2-61: ##STR00230## ##STR00231## ##STR00232## ##STR00233## ##STR00234## ##STR00235## ##STR00236## ##STR00237## ##STR00238## ##STR00239## ##STR00240## ##STR00241## ##STR00242## ##STR00243## ##STR00244## ##STR00245##

13. The composition of claim 1, wherein the first compound comprises at least one of Compounds 1, 5, 8, 9, 13, 14, 25 to 29, 33 to 43, and 48 to 52: ##STR00246## ##STR00247## ##STR00248## ##STR00249## ##STR00250## ##STR00251## ##STR00252## ##STR00253## ##STR00254## ##STR00255##

14. An organic light-emitting device comprising: a first electrode; a second electrode; and an organic layer disposed between the first electrode and the second electrode and comprising an emission layer, wherein the organic layer comprises the composition of claim 1.

15. The organic light-emitting device of claim 14, wherein the first electrode is an anode, the second electrode is a cathode, the organic layer further comprises 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, the hole transport region comprises a hole injection layer, a hole transport layer, an electron blocking layer, a buffer layer, or any combination thereof, and the electron transport region comprises a hole blocking layer, an electron transport layer, an electron injection layer, or any combination thereof.

16. The organic light-emitting device of claim 14, wherein the emission layer comprises the composition.

17. The organic light-emitting device of claim 14, wherein the emission layer emits red light.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) 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 FIGURE which is a schematic cross-sectional view of an organic light-emitting device according to an embodiment.

DETAILED DESCRIPTION

(2) Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. In this regard, the present embodiments may have different forms and should not be construed as being limited to the descriptions set forth herein. Accordingly, the embodiments are merely described below, by referring to the FIGURES, to explain aspects of the present description. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. Expressions such as “at least one of,” when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list.

(3) It will be understood that when an element is referred to as being “on” another element, it can be directly on the other element or intervening elements may be present therebetween. In contrast, when an element is referred to as being “directly on” another element, there are no intervening elements present.

(4) It will be understood that, although the terms “first,” “second,” “third” etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, “a first element,” “component,” “region,” “layer” or “section” discussed below could be termed a second element, component, region, layer or section without departing from the teachings herein.

(5) The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, “a,” “an,” “the,” and “at least one” do not denote a limitation of quantity, and are intended to cover both the singular and plural, unless the context clearly indicates otherwise. For example, “an element” has the same meaning as “at least one element,” unless the context clearly indicates otherwise.

(6) “Or” means “and/or.” As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. It will be further understood that the terms “comprises” and/or “comprising,” or “includes” and/or “including” when used in this specification, specify the presence of stated features, regions, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, components, and/or groups thereof.

(7) Furthermore, relative terms, such as “lower” or “bottom” and “upper” or “top,” may be used herein to describe one element's relationship to another element as illustrated in the FIGURES. It will be understood that relative terms are intended to encompass different orientations of the device in addition to the orientation depicted in the FIGURES. For example, if the device in one of the FIGURES is turned over, elements described as being on the “lower” side of other elements would then be oriented on “upper” sides of the other elements. The exemplary term “lower,” can therefore, encompasses both an orientation of “lower” and “upper,” depending on the particular orientation of the FIGURE. Similarly, if the device in one of the FIGURES is turned over, elements described as “below” or “beneath” other elements would then be oriented “above” the other elements. The exemplary terms “below” or “beneath” can, therefore, encompass both an orientation of above and below.

(8) “About” or “approximately” 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” can mean within one or more standard deviations, or within ±30%, 20%, 10% or 5% of the stated value.

(9) Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure, and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

(10) Exemplary embodiments are described herein with reference to cross section illustrations that are schematic illustrations of idealized embodiments. As such, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Thus, embodiments described herein should not be construed as limited to the particular shapes of regions as illustrated herein but are to include deviations in shapes that result, for example, from manufacturing. For example, a region illustrated or described as flat may, typically, have rough and/or nonlinear features. Moreover, sharp angles that are illustrated may be rounded. Thus, the regions illustrated in the figures are schematic in nature and their shapes are not intended to illustrate the precise shape of a region and are not intended to limit the scope of the present claims.

(11) A composition according to an embodiment may include a first compound, a second compound, and a third compound, and the first compound may include a compound represented by Formula 1, the second compound may include a compound represented by Formula 2, and the third compound may include a compound represented by Formula 3:

(12) ##STR00003##

(13) The first compound may include one compound encompassed in the first compound represented by Formula 1 only or at least two different compounds encompassed in the first compound represented by Formula 1.

(14) The second compound may include one compound encompassed in the second compound represented by Formula 2 only or at least two different compounds encompassed in the second compound represented by Formula 2.

(15) The third compound may include one compound encompassed in the third compound represented by Formula 3 only or at least two different compounds encompassed in the third compound represented by Formula 3.

(16) The first compound, the second compound and the third compound may be different from each other.

(17) Description of Formula 1

(18) Y.sub.2 in Formula 1 may be C.

(19) A ring CY.sub.12 in Formula 1 may be a C.sub.5-C.sub.60 carbocyclic group or a C.sub.1-C.sub.60 heterocyclic group.

(20) For example, the ring CY.sub.12 in Formula 1 may be i) a third ring, ii) a fourth ring, iii) a condensed cyclic group in which two or more third rings are condensed with each other, iv) a condensed cyclic group in which two or more fourth rings are condensed with each other, or v) a condensed cyclic group in which at least one third ring is condensed with at least one fourth ring,

(21) the third ring may be a cyclopentane group, a cyclopentadiene group, a furan group, a thiophene group, a pyrrole group, a silole group, an indene group, a benzofuran group, a benzothiophene group, an indole group, a benzosilole group, an oxazole group, an isoxazole group, an oxadiazole group, an isoxadiazole group, an oxatriazole group, an isoxatriazole group, a thiazole group, an isothiazole group, a thiadiazole group, an isothiadiazole group, a thiatriazole group, an isothiatriazole group, a pyrazole group, an imidazole group, a triazole group, a tetrazole group, an azasilole group, a diazasilole group, or a triazasilole group, and

(22) the fourth ring may be an adamantane group, a norbornene group, a bicyclo[1.1.1]pentane group, a bicyclo[2.1.1]hexane group, a bicyclo[2.2.1]heptane group (a norbornane group), a bicyclo[2.2.2]octane group, a cyclohexane group, a cyclohexene group, a benzene group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, or a triazine group.

(23) In one or more embodiments, the ring CY.sub.12 in Formula 1 may be a cyclopentane group, a cyclohexane group, a cyclohexene group, a benzene group, a naphthalene group, an anthracene group, a phenanthrene group, a triphenylene group, a pyrene group, a chrysene group, a 1,2,3,4-tetrahydronaphthalene group, a thiophene group, a furan group, a pyrrole group, a cyclopentadiene group, a silole group, a borole group, a phosphole group, a selenophene group, a germole group, a benzothiophene group, a benzofuran group, an indole group, an indene group, a benzosilole group, a benzoborole group, a benzophosphole group, a benzoselenophene group, a benzogermole group, a dibenzothiophene group, a dibenzofuran group, a carbazole group, a fluorene group, a dibenzosilole group, a dibenzoborole group, a dibenzophosphole group, a dibenzoselenophene group, a dibenzogermole group, a dibenzothiophene 5-oxide group, 9H-fluorene-9-one group, a dibenzothiophene 5,5-dioxide group, an azabenzothiophene group, an azabenzofuran group, an azaindole group, an azaindene group, an azabenzosilole group, an azabenzoborole group, an azabenzophosphole group, an azabenzoselenophene group, an azabenzogermole group, an azadibenzothiophene group, an azadibenzofuran group, an azacarbazole group, an azafluorene group, an azadibenzosilole group, an azadibenzoborole group, an azadibenzophosphole group, an azadibenzoselenophene group, an azadibenzogermole group, an azadibenzothiophene 5-oxide group, an aza-9H-fluorene-9-one group, an azadibenzothiophene 5,5-dioxide 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 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 5,6,7,8-tetrahydroisoquinoline group, a 5,6,7,8-tetrahydroquinoline group, an adamantane group, a norbornane group, or a norbornene group.

(24) In one or more embodiments, the ring CY.sub.12 may be a benzene group, a naphthalene group, a 1, 2, 3, 4-tetrahydronaphthalene group, a thiophene group, a furan group, a pyrrole group, a cyclopentadiene group, a silole group, a benzothiophene group, a benzofuran group, an indole group, an indene group, a benzosilole group, a dibenzothiophene group, a dibenzofuran group, a carbazole group, a fluorene group, or a dibenzosilole group.

(25) R.sub.1 to R.sub.8, A.sub.20 and A.sub.1 to A.sub.7 in Formula 1 may each independently be hydrogen, deuterium, —F, —Cl, —Br, —I, —SF.sub.5, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a substituted or unsubstituted C.sub.1-C.sub.60 alkyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkenyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkynyl group, a substituted or unsubstituted C.sub.1-C.sub.60 alkoxy group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.2-C.sub.10 heterocycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.2-C.sub.10 heterocycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryloxy group, a substituted or unsubstituted C.sub.6-C.sub.60 arylthio group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —N(Q.sub.1)(Q.sub.2), —Si(Q.sub.3)(Q.sub.4)(Q.sub.5), —Ge(Q.sub.3)(Q.sub.4)(Q.sub.5), —B(Q.sub.6)(Q.sub.7), —P(═O)(Q.sub.8)(Q.sub.9), or —P(Q.sub.8)(Q.sub.9). Q.sub.1 to Q.sub.9 are the same as described herein.

(26) In embodiments, A.sub.20 in Formula 1 may include neither a fluoro group (—F) nor a cyano group. For example, A.sub.20 may be a group that includes neither a fluoro group (—F) nor a cyano group.

(27) In one or more embodiments, R.sub.1 to R.sub.8, A.sub.20 and A.sub.1 to A.sub.7 in Formula 1 may each independently be:

(28) hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, —SF.sub.5, 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, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C.sub.1-C.sub.20 alkyl group, a deuterium-containing C.sub.1-C.sub.20 alkyl group, a fluorinated C.sub.1-C.sub.20 alkyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a bicyclo[1.1.1]pentyl group, a bicyclo[2.1.1]hexyl group, a bicyclo[2.2.1]heptyl group (a norbornyl group), a bicyclo[2.2.2]octyl group, a (C.sub.1-C.sub.20 alkyl)cyclopentyl group, a (C.sub.1-C.sub.20 alkyl)cyclohexyl group, a (C.sub.1-C.sub.20 alkyl)cycloheptyl group, a (C.sub.1-C.sub.20 alkyl)cyclooctyl group, a (C.sub.1-C.sub.20 alkyl)adamantyl group, a (C.sub.1-C.sub.20 alkyl)norbornenyl group, a (C.sub.1-C.sub.20 alkyl)cyclopentenyl group, a (C.sub.1-C.sub.20 alkyl)cyclohexenyl group, a (C.sub.1-C.sub.20 alkyl)cycloheptenyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[1.1.1]pentyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[2.1.1]hexyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[2.2.1]heptyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[2.2.2]octyl group, a silolanyl group, a phenyl group, a (C.sub.1-C.sub.20 alkyl)phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a 1,2,3,4-tetrahydronaphthyl group, a pyridinyl group, a pyrimidinyl group, or any combination thereof; a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a bicyclo[1.1.1]pentyl group, a bicyclo[2.1.1]hexyl group, a bicyclo[2.2.1]heptyl group, a bicyclo[2.2.2]octyl group, a silolanyl group, a phenyl group, a (C.sub.1-C.sub.20 alkyl)phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a 1,2,3,4-tetrahydronaphthyl 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, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl 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, or an azadibenzothiophenyl 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, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C.sub.1-C.sub.20 alkyl group, a deuterium-containing C.sub.1-C.sub.20 alkyl group, a fluorinated 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 adamantyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a bicyclo[1.1.1]pentyl group, a bicyclo[2.1.1]hexyl group, a bicyclo[2.2.1]heptyl group, a bicyclo[2.2.2]octyl group, a (C.sub.1-C.sub.20 alkyl)cyclopentyl group, a (C.sub.1-C.sub.20 alkyl)cyclohexyl group, a (C.sub.1-C.sub.20 alkyl)cycloheptyl group, a (C.sub.1-C.sub.20 alkyl)cyclooctyl group, a (C.sub.1-C.sub.20 alkyl)adamantyl group, a (C.sub.1-C.sub.20 alkyl)norbornenyl group, a (C.sub.1-C.sub.20 alkyl)cyclopentenyl group, a (C.sub.1-C.sub.20 alkyl)cyclohexenyl group, a (C.sub.1-C.sub.20 alkyl)cycloheptenyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[1.1.1]pentyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[2.1.1]hexyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[2.2.1]heptyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[2.2.2]octyl group, a silolanyl group, a phenyl group, a (C.sub.1-C.sub.20 alkyl)phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a 1,2,3,4-tetrahydronaphthyl 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, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl 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, or any combination thereof; or

(29) —N(Q.sub.1)(Q.sub.2), —Si(Q.sub.3)(Q.sub.4)(Q.sub.5), —Ge(Q.sub.3)(Q.sub.4)(Q.sub.5), —B(Q.sub.6)(Q.sub.7), —P(═O)(Q.sub.8)(Q.sub.9), or —P(Q.sub.8)(Q.sub.9),

(30) Q.sub.1 to Q.sub.9 may each independently be:

(31) —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

(32) 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, a phenyl group, a biphenyl group, or a naphthyl group, each unsubstituted or substituted with deuterium, a C.sub.1-C.sub.20 alkyl group, a phenyl group, or any combination thereof. Herein, A.sub.20 in Formula 1 may include neither a fluoro group (—F) nor a cyano group.

(33) In one or more embodiments, R.sub.1 to R.sub.8, A.sub.20 and A.sub.1 to A.sub.7 in Formula 1 may each independently be hydrogen, deuterium, —F, a substituted or unsubstituted C.sub.1-C.sub.20 alkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.2-C.sub.10 heterocycloalkyl group, a substituted or unsubstituted phenyl group, —Si(Q.sub.3)(Q.sub.4)(Q.sub.5), or —Ge(Q.sub.3)(Q.sub.4)(Q.sub.5). Herein, A.sub.20 may include neither a fluoro group nor a cyano group.

(34) In one or more embodiments, R.sub.1 to R.sub.8 and A.sub.1 to A.sub.7 in Formula 1 may each independently be:

(35) hydrogen, deuterium, or —F;

(36) a C.sub.1-C.sub.20 alkyl group, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.2-C.sub.10 heterocycloalkyl group, or a phenyl group, each unsubstituted or substituted with deuterium, —F, C.sub.1-C.sub.20 alkyl group, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.2-C.sub.10 heterocycloalkyl group, a phenyl group, or any combination thereof; or

(37) —Si(Q.sub.3)(Q.sub.4)(Q.sub.5), or —Ge(Q.sub.3)(Q.sub.4)(Q.sub.5).

(38) In one or more embodiments, A.sub.20 in Formula 1 may be:

(39) hydrogen or deuterium;

(40) a C.sub.1-C.sub.20 alkyl group, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.2-C.sub.10 heterocycloalkyl group, or a phenyl group, each unsubstituted or substituted with deuterium, a C.sub.1-C.sub.20 alkyl group, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.2-C.sub.10 heterocycloalkyl group, a phenyl group, or any combination thereof; or

(41) —Si(Q.sub.3)(Q.sub.4)(Q.sub.5), or —Ge(Q.sub.3)(Q.sub.4)(Q.sub.5).

(42) The designation d2 in Formula 1 indicates the number of A.sub.20(S), and may be an integer from 0 to 10. When d2 is 2 or more, two or more A.sub.20(S) may be identical to or different from each other. For example, d2 may be an integer from 0 to 6.

(43) For example, at least one of R.sub.1 to R.sub.8, A.sub.20 or any combination thereof in Formula 1 may include at least one fluoro group (—F).

(44) For example, at least one of R.sub.1 to R.sub.8 (for example, at least one of R.sub.2 to R.sub.8, or at least one of R.sub.3 to R.sub.6) of Formula 1 may include at least one fluoro group (—F).

(45) For example, at least one of R.sub.1 to R.sub.8 (for example, at least one of R.sub.2 to R.sub.8, or at least one of R.sub.3 to R.sub.6) of Formula 1 may be a group including at least one fluoro group (—F).

(46) In one or more embodiments, at least one of R.sub.1 to R.sub.8 in Formula 1 may each independently be:

(47) a fluoro group (—F); or

(48) a fluorinated C.sub.1-C.sub.20 alkyl group, a fluorinated C.sub.3-C.sub.10 cycloalkyl group, a fluorinated C.sub.2-C.sub.10 heterocycloalkyl group, or a fluorinated phenyl group, each unsubstituted or substituted with deuterium, a C.sub.1-C.sub.20 alkyl group, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.2-C.sub.10 heterocycloalkyl group, a phenyl group, or any combination thereof.

(49) In one or more embodiments, at least one of A.sub.1 to A.sub.6 in Formula 1 may each independently be a substituted or unsubstituted C.sub.2-C.sub.60 alkyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkenyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkynyl group, a substituted or unsubstituted C.sub.1-C.sub.60 alkoxy group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.2-C.sub.10 heterocycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.2-C.sub.10 heterocycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryloxy group, a substituted or unsubstituted C.sub.6-C.sub.60 arylthio group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, or a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group.

(50) In one or more embodiments, at least one of A.sub.1 to A.sub.6 in Formula 1 may each independently be a substituted or unsubstituted C.sub.2-C.sub.60 alkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, or a substituted or unsubstituted C.sub.2-C.sub.10 heterocycloalkyl group.

(51) In one or more embodiments, at least one of A.sub.1 to A.sub.3 and at least one of A.sub.4 to A.sub.6 in Formula 1 may each independently be a substituted or unsubstituted C.sub.2-C.sub.60 alkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, or a substituted or unsubstituted C.sub.2-C.sub.10 heterocycloalkyl group.

(52) In one or more embodiments, at least one of A.sub.1 to A.sub.6 in Formula 1 may each independently be a C.sub.2-C.sub.60 alkyl group, a C.sub.3-C.sub.10 cycloalkyl group, or a C.sub.2-C.sub.10 heterocycloalkyl group, each unsubstituted or substituted with deuterium, —F, a C.sub.1-C.sub.20 alkyl group, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.2-C.sub.10 heterocycloalkyl group, or any combination thereof.

(53) In one or more embodiments, A.sub.1 to A.sub.6 in Formula 1 may each independently be a substituted or unsubstituted C.sub.1-C.sub.60 alkyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkenyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkynyl group, a substituted or unsubstituted C.sub.1-C.sub.60 alkoxy group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.2-C.sub.10 heterocycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.2-C.sub.10 heterocycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryloxy group, a substituted or unsubstituted C.sub.6-C.sub.60 arylthio group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, or a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group.

(54) In one or more embodiments, A.sub.1 to A.sub.6 in Formula 1 may each independently be a substituted or unsubstituted C.sub.1-C.sub.60 alkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, or a substituted or unsubstituted C.sub.2-C.sub.10 heterocycloalkyl group.

(55) In one or more embodiments, A.sub.1 to A.sub.6 in Formula 1 may each independently be a C.sub.1-C.sub.60 alkyl group, a C.sub.3-C.sub.10 cycloalkyl group, or a C.sub.2-C.sub.10 heterocycloalkyl group, each unsubstituted or substituted with deuterium, —F, a C.sub.1-C.sub.20 alkyl group, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.2-C.sub.10 heterocycloalkyl group, or any combination thereof.

(56) In one or more embodiments, A.sub.7 in Formula 1 may be hydrogen or deuterium.

(57) In one or more embodiments, A.sub.7 in Formula 1 may not be hydrogen.

(58) In one or more embodiments, A.sub.7 in Formula 1 may be a substituted or unsubstituted C.sub.1-C.sub.60 alkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, or a substituted or unsubstituted C.sub.2-C.sub.10 heterocycloalkyl group.

(59) In one or more embodiments, A.sub.7 in Formula 1 may be a C.sub.1-C.sub.60 alkyl group, a C.sub.3-C.sub.10 cycloalkyl group, or a C.sub.2-C.sub.10 heterocycloalkyl group, each unsubstituted or substituted with deuterium, —F, a C.sub.1-C.sub.20 alkyl group, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.2-C.sub.10 heterocycloalkyl group, or any combination thereof.

(60) For example, R.sub.1 to R.sub.8, A.sub.20 and Ai to A.sub.7 in Formula 1 may each independently be hydrogen, deuterium, —F, —CH.sub.3, —CD.sub.3, —CD.sub.2H, —CDH.sub.2, —CF.sub.3, —CF.sub.2H, —CFH.sub.2, a group represented by one of Formulae 9-1 to 9-39, a group represented by one of Formulae 9-1 to 9-39 in which at least one hydrogen is substituted with deuterium, a group represented by one of Formulae 9-1 to 9-39 in which at least one hydrogen is substituted with —F, a group represented by one of Formulae 9-201 to 9-233, a group represented by one of Formulae 9-201 to 9-233 in which at least one hydrogen is substituted with deuterium, a group represented by one of Formulae 9-201 to 9-233 in which at least one hydrogen is substituted with —F, a group represented by one of Formulae 10-1 to 10-126, a group represented by one of Formulae 10-1 to 10-126 in which at least one hydrogen is substituted with deuterium, a group represented by one of Formulae 10-1 to 10-126 in which at least one hydrogen is substituted with —F, a group represented by one of Formulae 10-201 to 10-343, a group represented by one of Formulae 10-201 to 10-343 in which at least one hydrogen is substituted with deuterium, a group represented by one of Formulae 10-201 to 10-343 in which at least one hydrogen is substituted with —F, —Si(Q.sub.3)(Q.sub.4)(Q.sub.5), or —Ge(Q.sub.3)(Q.sub.4)(Q.sub.5) (herein Q.sub.3 to Q.sub.5 are the same as described in the present specification), and at least one of R.sub.1 to R.sub.8 (for example, at least one of R.sub.2 to R.sub.8, or at least one of R.sub.3 to R.sub.6) may be —F, —CF.sub.3, —CF.sub.2H, —CFH.sub.2, a group represented by one of Formulae 9-1 to 9-39 in which at least one hydrogen is substituted with —F, a group represented by one of Formulae 9-201 to 9-233 in which at least one hydrogen is substituted with —F, a group represented by one of Formulae 10-1 to 10-126 in which at least one hydrogen is substituted with —F, or a group represented by one of Formulae 10-201 to 10-343 in which at least one hydrogen is substituted with —F.

(61) In one or more embodiments, A.sub.20 in Formula 1 may be hydrogen, deuterium, —CH.sub.3, —CD.sub.3, —CD.sub.2H, —CDH.sub.2, a group represented by one of Formulae 9-1 to 9-39, a group represented by one of Formulae 9-1 to 9-39 in which at least one hydrogen is substituted with deuterium, a group represented by one of Formulae 9-201 to 9-233, a group represented by one of Formulae 9-201 to 9-233 in which at least one hydrogen is substituted with deuterium, a group represented by one of Formulae 10-1 to 10-126, a group represented by one of Formulae 10-1 to 10-126 in which at least one hydrogen is substituted with deuterium, a group represented by one of Formulae 10-201 to 10-343, a group represented by one of Formulae 10-201 to 10-343 in which at least one hydrogen is substituted with deuterium, —Si(Q.sub.3)(Q.sub.4)(Q.sub.5), or —Ge(Q.sub.3)(Q.sub.4)(Q.sub.5) (herein Q.sub.3 to Q.sub.5 are the same as described in the present specification).

(62) In one or more embodiments, at least one of A.sub.1 to A.sub.6 in Formula 1 may each independently be a group represented by one of Formulae 9-1 to 9-39, a group represented by one of Formulae 9-1 to 9-39 in which at least one hydrogen is substituted with deuterium, a group represented by one of Formulae 9-1 to 9-39 in which at least one hydrogen is substituted with —F, a group represented by one of Formulae 9-201 to 9-233, a group represented by one of Formulae 9-201 to 9-233 in which at least one hydrogen is substituted with deuterium, a group represented by one of Formulae 9-201 to 9-233 in which at least one hydrogen is substituted with —F, a group represented by one of Formulae 10-1 to 10-126, a group represented by one of Formulae 10-1 to 10-126 in which at least one hydrogen is substituted with deuterium, a group represented by one of Formulae 10-1 to 10-126 in which at least one hydrogen is substituted with —F, a group represented by one of Formulae 10-201 to 10-343, a group represented by one of Formulae 10-201 to 10-343 in which at least one hydrogen is substituted with deuterium, or a group represented by one of Formulae 10-201 to 10-343 in which at least one hydrogen is substituted with —F.

(63) In one or more embodiments, A.sub.1 to A.sub.6 in Formula 1 may each independently be —CH.sub.3, —CD.sub.3, —CD.sub.2H, —CDH.sub.2, —CF.sub.3, —CF.sub.2H, —CFH.sub.2, a group represented by one of Formulae 9-1 to 9-39, a group represented by one of Formulae 9-1 to 9-39 in which at least one hydrogen is substituted with deuterium, a group represented by one of Formulae 9-1 to 9-39 in which at least one hydrogen is substituted with —F, a group represented by one of Formulae 9-201 to 9-233, a group represented by one of Formulae 9-201 to 9-233 in which at least one hydrogen is substituted with deuterium, a group represented by one of Formulae 9-201 to 9-233 in which at least one hydrogen is substituted with —F, a group represented by one of Formulae 10-1 to 10-126, a group represented by one of Formulae 10-1 to 10-126 in which at least one hydrogen is substituted with deuterium, a group represented by one of Formulae 10-1 to 10-126 in which at least one hydrogen is substituted with —F, a group represented by one of Formulae 10-201 to 10-343, a group represented by one of Formulae 10-201 to 10-343 in which at least one hydrogen is substituted with deuterium, or a group represented by one of Formulae 10-201 to 10-343 in which at least one hydrogen is substituted with —F:

(64) ##STR00004## ##STR00005## ##STR00006## ##STR00007## ##STR00008## ##STR00009## ##STR00010## ##STR00011## ##STR00012## ##STR00013## ##STR00014## ##STR00015## ##STR00016## ##STR00017## ##STR00018## ##STR00019## ##STR00020## ##STR00021## ##STR00022## ##STR00023## ##STR00024##

(65) ##STR00025## ##STR00026## ##STR00027## ##STR00028## ##STR00029## ##STR00030## ##STR00031## ##STR00032## ##STR00033## ##STR00034## ##STR00035## ##STR00036## ##STR00037## ##STR00038## ##STR00039## ##STR00040##

(66) * in Formulae 9-1 to 9-39, 9-201 to 9-233, 10-1 to 10-126, and 10-201 to 10-343 indicates a binding site to a neighboring atom, Ph is a phenyl group, TMS is a trimethylsilyl group, and TMG is a trimethylgermyl group.

(67) The “group represented by one of Formulae 9-1 to 9-39 in which at least one hydrogen is substituted with deuterium” and the “group represented by one of Formulae 9-201 to 9-233 in which at least one hydrogen is substituted with deuterium” may each be, for example, a group represented by one of Formulae 9-501 to 9-514 and 9-601 to 9-635:

(68) ##STR00041## ##STR00042## ##STR00043## ##STR00044## ##STR00045## ##STR00046##

(69) The “group represented by one of Formulae 9-1 to 9-39 in which at least one hydrogen is substituted with —F” and the “group represented by one of Formulae 9-201 to 9-233 in which at least one hydrogen is substituted with —F” may each be, for example, a group represented by one of Formulae 9-701 to 9-710:

(70) ##STR00047##

(71) The “group represented by one of Formulae 10-1 to 10-126 in which at least one hydrogen is substituted with deuterium” and the “group represented by one of Formulae 10-201 to 10-343 in which at least one hydrogen is substituted with deuterium” may each be, for example, a group represented by one of Formulae 10-501 to 10-553:

(72) ##STR00048## ##STR00049## ##STR00050## ##STR00051## ##STR00052## ##STR00053## ##STR00054##

(73) The “group represented by one of Formulae 10-1 to 10-126 in which at least one hydrogen is substituted with —F” and the “group represented by one of Formulae 10-201 to 10-343 in which at least one hydrogen is substituted with —F” may each be, for example, a group represented by one of Formulae 10-601 to 10-617:

(74) ##STR00055## ##STR00056##

(75) In one or more embodiments, in Formula 1,

(76) 1) R.sub.2 may include at least one fluoro group (—F);

(77) 2) R.sub.3 may include at least one fluoro group (—F);

(78) 3) R.sub.4 may include at least one fluoro group (—F);

(79) 4) R.sub.5 may include at least one fluoro group (—F);

(80) 5) R.sub.6 may include at least one fluoro group (—F);

(81) 6) R.sub.7 may include at least one fluoro group (—F);

(82) 7) R.sub.8 may include at least one fluoro group (—F);

(83) 8) R.sub.4 and R.sub.5 may each include at least one fluoro group (—F);

(84) 9) R.sub.4 and R.sub.6 may each include at least one fluoro group (—F);

(85) 10) R.sub.5 and R.sub.6 may each include at least one fluoro group (—F);

(86) 11) R.sub.3 and R.sub.4 may each include at least one fluoro group (—F); or

(87) 12) R.sub.3 and R.sub.6 may each include at least one fluoro group (—F).

(88) In one or more embodiments, regarding Formula 1,

(89) one or two of R.sub.1 to R.sub.8 may each independently include at least one fluoro group (—F), and

(90) at least one of R.sub.1 to R.sub.8 i) may not include a fluoro group (—F), and ii) may not be hydrogen.

(91) In one or more embodiments, A.sub.20 in Formula 1 may be a C.sub.1-C.sub.20 alkyl group, a C.sub.3-C.sub.10 cycloalkyl group, or a C.sub.2-C.sub.10 heterocycloalkyl group, each unsubstituted or substituted with deuterium, a C.sub.1-C.sub.20 alkyl group, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.2-C.sub.10 heterocycloalkyl group, or any combination thereof.

(92) In one or more embodiments, A.sub.20 in Formula 1 may be a C.sub.1-C.sub.20 alkyl group, unsubstituted or substituted with deuterium, a C.sub.1-C.sub.20 alkyl group, or any combination thereof.

(93) In one or more embodiments, d2 in Formula 1 may be 2.

(94) In one or more embodiments, A.sub.20 in Formula 1 may be a C.sub.1-C.sub.20 alkyl group, unsubstituted or substituted with deuterium, a C.sub.1-C.sub.20 alkyl group, or any combination thereof, and d2 may be 2.

(95) In one or more embodiments, the organometallic compound represented by Formula 1 may have at least one deuterium.

(96) In one or more embodiments, at least one of R.sub.1 to R.sub.8 of Formula 1 may have at least one deuterium.

(97) In one or more embodiments, at least one of R.sub.20 in number of d2 may have at least one deuterium.

(98) In one or more embodiments, at least one of R.sub.20 in number of d2 may be a deuterium-containing C.sub.1-C.sub.20 alkyl group, a deuterium-containing C.sub.3-C.sub.10 cycloalkyl group, or a deuterium-containing C.sub.2-C.sub.10 heterocycloalkyl group, each unsubstituted or substituted with a C.sub.1-C.sub.20 alkyl group, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.2-C.sub.10 heterocycloalkyl group, or any combination thereof.

(99) In one or more embodiments, a group represented by

(100) ##STR00057##
in Formula 1 may be a group represented by one of Formulae CY1 to CY108:

(101) ##STR00058## ##STR00059## ##STR00060## ##STR00061## ##STR00062## ##STR00063## ##STR00064## ##STR00065## ##STR00066## ##STR00067## ##STR00068## ##STR00069## ##STR00070## ##STR00071## ##STR00072## ##STR00073## ##STR00074## ##STR00075## ##STR00076##

(102) In Formulae CY1 to CY108,

(103) T.sub.2 to T.sub.8 may each independently be:

(104) a fluoro group (—F); or

(105) a fluorinated C.sub.1-C.sub.20 alkyl group, a fluorinated C.sub.3-C.sub.10 cycloalkyl group, a fluorinated C.sub.2-C.sub.10 heterocycloalkyl group, or a fluorinated phenyl group, each unsubstituted or substituted with deuterium, a C.sub.1-C.sub.20 alkyl group, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.2-C.sub.10 heterocycloalkyl group, a phenyl group, or any combination thereof;

(106) each of R.sub.2 to R.sub.8 and R.sub.1a are the same as described above, and R.sub.2 to R.sub.8 may not be hydrogen,

(107) * indicates a binding site to Ir in Formula 1,

(108) *″ indicates a binding site to a neighboring atom in Formula 1.

(109) For example, R.sub.2 to R.sub.8 in Formulae CY1 to CY108 may each independently be:

(110) deuterium; or

(111) a C.sub.1-C.sub.20 alkyl group, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.2-C.sub.10 heterocycloalkyl group, or a phenyl group, each unsubstituted or substituted with deuterium, a C.sub.1-C.sub.20 alkyl group, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.2-C.sub.10 heterocycloalkyl group, a phenyl group, or any combination thereof.

(112) In one or more embodiments, the group represented by

(113) ##STR00077##
in Formula 1 may be a group represented by one of Formulae A(1) to A(7):

(114) ##STR00078## ##STR00079##

(115) In Formulae A(1) to A(7),

(116) Y.sub.2 may be C,

(117) X.sub.21 may be O, S, N(R.sub.25), (R.sub.25)(R.sub.26), or Si(R.sub.25)(R.sub.26),

(118) each of R.sub.9 to R.sub.12 and R.sub.21 to R.sub.26 may be the same as described in connection with A.sub.20,

(119) *′ may indicate a binding site to Ir in Formula 1, and

(120) *″ may indicate a binding site to a neighboring atom in Formula 1.

(121) For example, R.sub.9 and R.sub.11 in Formula A(1) may each independently be a C.sub.1-C.sub.20 alkyl group, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.2-C.sub.10 heterocycloalkyl group, or a phenyl group, each unsubstituted or substituted with deuterium, a C.sub.1-C.sub.20 alkyl group, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.2-C.sub.10 heterocycloalkyl group, a phenyl group, or any combination thereof.

(122) In one or more embodiments, R.sub.9 and R.sub.11 in Formula A(1) may each independently be a C.sub.1-C.sub.20 alkyl group, unsubstituted or substituted with deuterium, a C.sub.1-C.sub.20 alkyl group, or any combination thereof.

(123) In one or more embodiments, R.sub.10 and R.sub.12 in Formula A(1) may each independently be hydrogen or deuterium.

(124) In one or more embodiments, R.sub.9 and R.sub.11 in Formula A(1) may be identical to each other.

(125) In one or more embodiments, R.sub.9 and R.sub.11 in Formula A(1) may be different from each other.

(126) In one or more embodiments, R.sub.9 and R.sub.11 in Formula A(1) may be different from each other, and the number of carbons included in R.sub.11 may be greater than the number of carbon included in R.sub.9.

(127) In one or more embodiments, i) at least one of R.sub.9 to R.sub.12 in Formula A(1), ii) R.sub.11, R.sub.12, one of R.sub.21 to R.sub.26, or any combination thereof in Formulae A(2) and A(3), iii) R.sub.9, R.sub.12, one of R.sub.21 to R.sub.26, or any combination thereof in Formulae A(4) and A(5), and iv) R.sub.9, R.sub.10, one of R.sub.21 to R.sub.26, or any combination thereof in Formulae A(6) and A(7), may each independently be a deuterium-containing C.sub.1-C.sub.20 alkyl group, a deuterium-containing C.sub.3-C.sub.10 cycloalkyl group, or a deuterium-containing C.sub.2-C.sub.10 heterocycloalkyl group, each unsubstituted or substituted with a C.sub.1-C.sub.20 alkyl group, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.2-C.sub.10 heterocycloalkyl group, or any combination thereof.

(128) In one or more embodiments, at least one of R.sub.9 and R.sub.1 in Formula A(1) (for example, R.sub.9 and R.sub.11 in Formula A(1)) may each independently be a deuterium-containing C.sub.1-C.sub.20 alkyl group, a deuterium-containing C.sub.3-C.sub.10 cycloalkyl group, or a deuterium-containing C.sub.2-C.sub.10 heterocycloalkyl group, each unsubstituted or substituted with a C.sub.1-C.sub.20 alkyl group, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.2-C.sub.10 heterocycloalkyl group, or any combination thereof.

(129) In one or more embodiments, the group represented by

(130) ##STR00080##
in Formula 1 may be a group represented by Formula A(1) or A(5).

(131) In one or more embodiments, the number of carbons included in the group represented by *—C(A)(A.sub.2)(A.sub.3) in Formula 1 may be 5 or more, and/or the number of carbons included in the group represented by *—C(A.sub.4)(A.sub.5)(A.sub.6) in Formula 1 may be 5 or more.

(132) In one or more embodiments, A.sub.1, A.sub.2, and A.sub.3 of the group represented by *—C(A.sub.1)(A.sub.2)(A.sub.3) in Formula 1 may be linked to each other to form a C.sub.5-C.sub.60 carbocyclic group which is unsubstituted or substituted with at least one R.sub.1a or a C.sub.1-C.sub.60 heterocyclic group which is unsubstituted or substituted with at least one R.sub.1a. That is, the group represented by *—C(Ai)(A.sub.2)(A.sub.3) in Formula 1 may be a C.sub.5-C.sub.60 carbocyclic group which is unsubstituted or substituted with at least one R.sub.1a or a C.sub.1-C.sub.60 heterocyclic group which is unsubstituted or substituted with at least one R.sub.1a (for example, an adamantane group, a norbornene group, a bicyclo[1.1.1]pentane group, a bicyclo[2.1.1]hexane group, a bicyclo[2.2.1]heptane group (a norbornane group), a bicyclo[2.2.2]octane group, a cyclopentane group, a cyclohexane group, or a cyclohexene group, each unsubstituted or substituted with at least one R.sub.1a).

(133) In one or more embodiments, A.sub.4, As, and A.sub.6 of the group represented by *—C(A.sub.4)(A.sub.5)(A.sub.6) in Formula 1 may be linked to each other to form a C.sub.5-C.sub.60 carbocyclic group which is unsubstituted or substituted with at least one R.sub.1a or a C.sub.1-C.sub.60 heterocyclic group which is unsubstituted or substituted with at least one R.sub.1a. That is, the group represented by *—C(A.sub.4)(A.sub.5)(A.sub.6) in Formula 1 may be a C.sub.5-C.sub.60 carbocyclic group which is unsubstituted or substituted with at least one R.sub.1a or a C.sub.1-C.sub.60 heterocyclic group which is unsubstituted or substituted with at least one R.sub.1a (for example, an adamantane group, a norbornene group, a bicyclo[1.1.1]pentane group, a bicyclo[2.1.1]hexane group, a bicyclo[2.2.1]heptane group (a norbornane group), a bicyclo[2.2.2]octane group, a cyclopentane group, a cyclohexane group, or a cyclohexene group, each unsubstituted or substituted with at least one R.sub.1a).

(134) In one or more embodiments, in Formula 1, a group represented by *—C(Ai)(A.sub.2)(A.sub.3) may be identical to a group represented by *—C(A.sub.4)(A.sub.5)(A.sub.6).

(135) In one or more embodiments, in Formula 1, a group represented by *—C(Ai)(A.sub.2)(A.sub.3) may be different from a group represented by *—C(A.sub.4)(A.sub.5)(A.sub.6).

(136) In one or more embodiments, the first compound may include at least one of Compounds 1 to 53:

(137) ##STR00081## ##STR00082## ##STR00083## ##STR00084## ##STR00085## ##STR00086## ##STR00087## ##STR00088## ##STR00089## ##STR00090## ##STR00091## ##STR00092## ##STR00093## ##STR00094##

(138) The first compound may include an organometallic compound represented by Formula 1. In an organometallic compound represented by Formula 1, 1) ring CY.sub.11 (see Formula 1′) is, as illustrated in Formula 1, a condensed cyclic group in which two benzene groups are condensed with one pyridine group, and 2) at least one of R.sub.1 to R.sub.8, A.sub.20, or any combination thereof includes at least one a fluoro group (—F). Accordingly, the transition dipole moment of the organometallic compounds may be increased, and the conjugation length of the organometallic compounds may be relatively increased and structural rigidity thereof may be increased, leading to a decrease in non-radiative transition. Thus, an electronic device, for example, an organic light-emitting device, including the organometallic compound represented by Formula 1 may have high external quantum efficiency (EQE), and thus, may have high luminescence efficiency.

(139) Formula 1′

(140) ##STR00095##

(141) In one or more embodiments, when at least one of A.sub.1 to A.sub.6 in Formula 1 is each independently be a substituted or unsubstituted C.sub.2-C.sub.60 alkyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkenyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkynyl group, a substituted or unsubstituted C.sub.1-C.sub.60 alkoxy group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.2-C.sub.10 heterocycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.2-C.sub.10 heterocycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryloxy group, a substituted or unsubstituted C.sub.6-C.sub.60 arylthio group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, or a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group (that is, when at least one of A.sub.1 to A.sub.6 in Formula 1 has two or more carbons), an electron donating capability of Ligand 2 (see Formula 1′) in Formula 1 may be improved, and thus, an interaction between Ligand 1 and Ligand 2 in Formula 1 may be enhanced. Thus, the organometallic compound represented by Formula 1 may have improved luminescent transition characteristics, improved optical orientation characteristics, and improved structural rigidity. Accordingly, an electronic device, for example, an organic light-emitting device, including the organometallic compound represented by Formula 1 may have high luminescence efficiency and a long lifespan.

(142) In one or more embodiments, when A.sub.1 to A.sub.6 in Formula 1 are each independently a substituted or unsubstituted C.sub.1-C.sub.60 alkyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkenyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkynyl group, a substituted or unsubstituted C.sub.1-C.sub.60 alkoxy group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.2-C.sub.10 heterocycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.2-C.sub.10 heterocycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryloxy group, a substituted or unsubstituted C.sub.6-C.sub.60 arylthio group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, or a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group (that is, when A.sub.1 to A.sub.6 in Formula 1 each have one or more carbons), carbons bound to each A.sub.1 to A.sub.6 in Formula 1 as described above may not include an α-proton, and in this regard, the organometallic compound represented by Formula 1 may have a stable chemical structure with minimal occurrence of a side reaction before/after synthesis, and at the same time, an intermolecular interaction of the organometallic compound represented by Formula 1 may be minimized during the operation of an electronic device (for example, an organic light-emitting device) including the organometallic compound represented by Formula 1. Furthermore, an interaction between Ligand 1 and Ligand 2 in Formula 1 may be enhanced and thus, the organometallic compound represented by Formula 1 may have improved structural rigidity, a full width at half maximum (FWHM) in the photoluminescent spectrum or electroluminescent spectrum of the organometallic compound represented by Formula 1 may be reduced, and a vibronic state of the organometallic compound represented by Formula 1 may be reduced. Accordingly a non-radiative decay of the organometallic compound represented by Formula 1 can be reduced and thus an electronic device, for example, an organic light-emitting device, including the organometallic compound represented by Formula 1 may have high luminescence efficiency and long lifespan.

(143) Synthesis methods of the first compound may be recognizable by one of ordinary skill in the art by referring to Synthesis Examples provided below.

(144) Description of Formulae 2 and 3

(145) Ar.sub.1, Ar.sub.2, and Ar.sub.11 in Formulae 2 and 3 may each independently be a C.sub.5-C.sub.60 carbocyclic group which is unsubstituted or substituted with at least one R.sub.61 or a C.sub.1-C.sub.60 heterocyclic group which is unsubstituted or substituted with at least one R.sub.61,

(146) Ar.sub.5 and Ar.sub.12 in Formulae 2 and 3 may each independently be a single bond, a C.sub.5-C.sub.60 carbocyclic group which is unsubstituted or substituted with at least one R.sub.65, or a C.sub.1-C.sub.60 heterocyclic group which is unsubstituted or substituted with at least one R.sub.65, or may not exist,

(147) n in Formula 2 may be 1, 2, or 3, and when n is 1, Ar.sub.5 does not exist,

(148) p in Formula 3 may be 1, 2, or 3, and when p is 1, Ar.sub.12 does not exist,

(149) a1 and a2 in Formula 2 may each independently be an integer from 0 to 5, and the sum of a1 and a2 is 1 or more,

(150) ring CY.sub.2 and ring CY.sub.3 in Formula 2 may each independently be a C.sub.5-C.sub.60 carbocyclic group or a C.sub.1-C.sub.60 heterocyclic group, and ring CY.sub.2 and ring CY.sub.3 may be optionally linked to each other with a C.sub.5-C.sub.60 carbocyclic group which is unsubstituted or substituted with at least one R.sub.66 or a C.sub.1-C.sub.60 heterocyclic group which is unsubstituted or substituted with at least one R.sub.66 therebetween,

(151) Het1 in Formula 3 may be a π electron-depleted nitrogen-containing C.sub.1-C.sub.60 cyclic group, and

(152) a11 and m in Formula 3 may each independently be an integer from 1 to 10.

(153) The term “a π electron-depleted nitrogen-containing C.sub.1-C.sub.60 cyclic group” may be a cyclic group having 1 to 60 carbon atoms and at least one *—N═*′ as a ring-forming moiety. The examples of π electron-depleted nitrogen-containing C.sub.1-C.sub.60 cyclic group may include a) a first ring, b) a condensed ring in which at least first rings or c) a condensed ring in which at least one first ring and at least one second ring are condensed. The examples of the first ring and the second ring may be understood by referring the descriptions herein.

(154) For example, the π electron-depleted nitrogen-containing C.sub.1-C.sub.60 cyclic group may be an imidazole group, a pyrazole group, a thiazole group, an isothiazole group, an oxazole group, an isoxazole group, a pyridine group, a pyrazine group, a pyridazine group, a pyrimidine group, an indazole group, a purine group, a quinoline group, an isoquinoline group, a benzoquinoline group, a benzoisoquinoline group, a phthalazine group, a naphthyridine group, a quinoxaline group, a benzoquinoxaline group, a quinazoline group, a cinnoline group, a phenanthridine group, an acridine group, a phenanthroline group, a phenazine group, a benzimidazole group, an isobenzothiazole group, a benzoxazole group, an isobenzoxazole group, a triazole group, a tetrazole group, an oxadiazole group, a triazine group, a thiadiazole group, an imidazopyridine group, an imidazopyrimidine group, an azacarbazole group, an azadibenzofuran group, an azadibenzothiophene group, an azadibenzosilole group, a benzonaphthofuran group, a benzonaphthothiophene group, an indolophenanthrene group, a benzofuranophenanthrene group, a benzothienophenanthrene group, or a pyridopyrazine group.

(155) The term “a π electron-rich C.sub.3-C.sub.60 cyclic group” may be a cyclic group having 3 to 60 carbon atoms and not having *—N═*′ as a ring-forming moiety. The examples of π electron-rich C.sub.3-C.sub.60 cyclic group may include a) a second ring, or b) a condensed ring in which at least second rings. The examples of the second ring may be understood by referring the descriptions herein.

(156) For example, the π electron-rich C.sub.3-C.sub.60 cyclic group may be a benzene group, a heptalene group, an indene group, a naphthalene group, an azulene group, a heptalene group, an indacene group, an acenaphthylene group, a fluorene group, a spiro-bifluorene group, a benzofluorene group, a dibenzofluorene group, a phenalene group, a phenanthrene group, an anthracene group, a fluoranthene group, a triphenylene group, a pyrene group, a chrysene group, a naphthacene group, a picene group, a perylene group, a pentacene group, a hexacene group, a pentaphene group, a rubicene group, a coronene group, an ovalene group, a pyrrole group, a furan group, a thiophene group, an isoindole group, an indole group, an indene group, a benzofuran group, a benzothiophene group, a benzosilole group, a naphthopyrrole group, a naphthofuran group, a naphthothiophene group, a naphthosilole group, a benzocarbazole group, a dibenzocarbazole group, a dibenzofuran group, a dibenzothiophene group, a dibenzothiophene sulfone group, a carbazole group, a dibenzosilole group, an indenocarbazole group, an indolocarbazole group, a benzofurocarbazole group, a benzothienocarbazole group, a benzosilolocarbazole group, a triindolobenzene group, an acridine group, a dihydroacridine group, a pyrrolophenanthrene group, a furanophenanthrene group, or a thienophenanthrene group.

(157) In one or more embodiments,

(158) Ar.sub.1, Ar.sub.2, and Ar.sub.11 in Formulae 2 and 3 may each independently be a group derived from i) a first ring unsubstituted or substituted with at least one R.sub.61, ii) a second ring unsubstituted or substituted with at least one R.sub.61, iii) a condensed cyclic group in which two or more first rings are condensed with each other, unsubstituted or substituted with at least one R.sub.61, iv) a condensed cyclic group in which two or more second rings are condensed with each other, unsubstituted or substituted with at least one R.sub.61, or v) a condensed cyclic group in which at least one first ring and at least one second ring are condensed with each other, unsubstituted or substituted with at least one R.sub.61,

(159) Ar.sub.5 and Ar.sub.12 in Formulae 2 and 3 may each independently be a single bond, or a group derived from i) a first ring unsubstituted or substituted with at least one R.sub.65, ii) a second ring unsubstituted or substituted with at least one R.sub.65, iii) a condensed cyclic group in which two or more first rings are condensed with each other, unsubstituted or substituted with at least one R.sub.65, iv) a condensed cyclic group in which two or more second rings are condensed with each other, unsubstituted or substituted with at least one R.sub.65, or v) a condensed cyclic group in which at least one first ring and at least one second ring are condensed with each other, unsubstituted or substituted with at least one R.sub.65, or may not exist,

(160) ring CY.sub.2 and ring CY.sub.3 in Formula 2 may each independently be i) a first ring, ii) a second ring, iii) a condensed cyclic group in which two or more first rings are condensed with each other, iv) a condensed cyclic group in which two or more second rings are condensed with each other, or v) a condensed cyclic group in which at least one first ring and at least one second ring are condensed with each other,

(161) Het1 in Formula 3 may be a group derived from i) a first ring, ii) a condensed cyclic group in which two or more first rings are condensed with each other or iii) a condensed cyclic group in which at least one first ring and at least one second ring are condensed with each other,

(162) the first ring may be an imidazole group, a pyrazole group, a thiazole group, an isothiazole group, an oxazole group, an isoxazole group, a pyridine group, a pyrazine group, a pyridazine group, a pyrimidine group, a triazole group, a tetrazole group, an oxadiazole group, a triazine group, or a thiadiazole group, and

(163) the second ring may be a benzene group, a cyclopentadiene group, a pyrrole group, a furan group, a thiophene group, or a silole group.

(164) In one or more embodiments, Ar.sub.1, Ar.sub.2, and Ar.sub.11 in Formulae 2 and 3 may each independently be a benzene group, a heptalene group, an indene group, a naphthalene group, an azulene group, a heptalene group, an indacene group, an acenaphthylene group, a fluorene group, a spiro-bifluorene group, a benzofluorene group, a dibenzofluorene group, a phenalene group, a phenanthrene group, an anthracene group, a fluoranthene group, a triphenylene group, a pyrene group, a chrysene group, a naphthacene group, a picene group, a perylene group, a pentacene group, a hexacene group, a pentaphene group, a rubicene group, a coronene group, an ovalene group, a pyrrole group, a furan group, a thiophene group, an isoindole group, an indole group, an indene group, a benzofuran group, a benzothiophene group, a benzosilole group, a naphthopyrrole group, a naphthofuran group, a naphthothiophene group, a naphthosilole group, a benzocarbazole group, a dibenzocarbazole group, a dibenzofuran group, a dibenzothiophene group, a dibenzothiophene sulfone group, a carbazole group, a dibenzosilole group, an indenocarbazole group, an indolocarbazole group, a benzofurocarbazole group, a benzothienocarbazole group, a benzosilolocarbazole group, a triindolobenzene group, an acridine group, a dihydroacridine group, an imidazole group, a pyrazole group, a thiazole group, an isothiazole group, an oxazole group, an isoxazole group, a pyridine group, a pyrazine group, a pyridazine group, a pyrimidine group, an indazole group, a purine group, a quinoline group, an isoquinoline group, a benzoquinoline group, a benzoisoquinoline group, a phthalazine group, a naphthyridine group, a quinoxaline group, a benzoquinoxaline group, a quinazoline group, a cinnoline group, a phenanthridine group, an acridine group, a phenanthroline group, a phenazine group, a benzimidazole group, an isobenzothiazole group, a benzoxazole group, an isobenzoxazole group, a triazole group, a tetrazole group, an oxadiazole group, a triazine group, a thiadiazole group, an imidazopyridine group, an imidazopyrimidine group, an azacarbazole group, an azadibenzofuran group, an azadibenzothiophene group, an azadibenzosilole group, a benzonaphthofuran group, a benzonaphthothiophene group, an indolophenanthrene group, a benzofuranophenanthrene group, or a benzothienophenanthrene group, each unsubstituted or substituted with at least one R.sub.61.

(165) In one or more embodiments, Ar.sub.5 and Ar.sub.12 in Formulae 2 and 3 may each independently be a single bond, a benzene group, a naphthalene group, or a carbazole group, each unsubstituted or substituted with at least one R.sub.61, or may not exist.

(166) In one or more embodiments, ring CY.sub.2 and ring CY.sub.3 in Formula 2 may each independently be a benzene group, a heptalene group, an indene group, a naphthalene group, an azulene group, a heptalene group, an indacene group, an acenaphthylene group, a fluorene group, a spiro-bifluorene group, a benzofluorene group, a dibenzofluorene group, a phenalene group, a phenanthrene group, an anthracene group, a fluoranthene group, a triphenylene group, a pyrene group, a chrysene group, a naphthacene group, a picene group, a perylene group, a pentacene group, a hexacene group, a pentaphene group, a rubicene group, a coronene group, an ovalene group, a pyrrole group, a furan group, a thiophene group, an isoindole group, an indole group, an indene group, a benzofuran group, a benzothiophene group, a benzosilole group, a naphthopyrrole group, a naphthofuran group, a naphthothiophene group, a naphthosilole group, a benzocarbazole group, a dibenzocarbazole group, a dibenzofuran group, a dibenzothiophene group, a dibenzothiophene sulfone group, a carbazole group, a dibenzosilole group, an indenocarbazole group, an indolocarbazole group, a benzofurocarbazole group, a benzothienocarbazole group, a benzosilolocarbazole group, a triindolobenzene group, an acridine group, a dihydroacridine group, an imidazole group, a pyrazole group, a thiazole group, an isothiazole group, an oxazole group, an isoxazole group, a pyridine group, a pyrazine group, a pyridazine group, a pyrimidine group, an indazole group, a purine group, a quinoline group, an isoquinoline group, a benzoquinoline group, a benzoisoquinoline group, a phthalazine group, a naphthyridine group, a quinoxaline group, a benzoquinoxaline group, a quinazoline group, a cinnoline group, a phenanthridine group, an acridine group, a phenanthroline group, a phenazine group, a benzimidazole group, an isobenzothiazole group, a benzoxazole group, an isobenzoxazole group, a triazole group, a tetrazole group, an oxadiazole group, a triazine group, a thiadiazole group, an imidazopyridine group, an imidazopyrimidine group, an azacarbazole group, an azadibenzofuran group, an azadibenzothiophene group, an azadibenzosilole group, a pyrrolophenanthrene group, a furanophenanthrene group, or a thienophenanthrene group.

(167) In one or more embodiments, Het1 in Formula 3 may be an imidazole group, a pyrazole group, a thiazole group, an isothiazole group, an oxazole group, an isoxazole group, a pyridine group, a pyrazine group, a pyridazine group, a pyrimidine group, an indazole group, a purine group, a quinoline group, an isoquinoline group, a benzoquinoline group, a benzoisoquinoline group, a phthalazine group, a naphthyridine group, a quinoxaline group, a benzoquinoxaline group, a quinazoline group, a cinnoline group, a phenanthridine group, an acridine group, a phenanthroline group, a phenazine group, a benzimidazole group, an isobenzothiazole group, a benzoxazole group, an isobenzoxazole group, a triazole group, a tetrazole group, an oxadiazole group, a triazine group, a thiadiazole group, an imidazopyridine group, an imidazopyrimidine group, an azacarbazole group, an azadibenzofuran group, an azadibenzothiophene group, an azadibenzosilole group, or a pyridopyrazine group.

(168) In one or more embodiments, Ar.sub.1, Ar.sub.2, and Ar.sub.11 in Formulae 2 and 3 may each independently be a π electron-rich C.sub.3-C.sub.60 cyclic group unsubstituted or substituted with at least one R.sub.61.

(169) In one or more embodiments, Ar.sub.5 and Ar.sub.12 in Formulae 2 and 3 may each independently be a single bond or a π electron-rich C.sub.3-C.sub.60 cyclic group unsubstituted or substituted with at least one R.sub.65, or may not exist.

(170) In one or more embodiments, ring CY.sub.2 and ring CY.sub.3 in Formula 2 may each independently be a π electron-rich C.sub.3-C.sub.60 cyclic group.

(171) In one or more embodiments, n and p in Formulae 2 and 3 may each independently be 1 or 2.

(172) In one or more embodiments, in Formula 2, when n is 1, at least one of the ring CY.sub.2 and the ring CY.sub.3 may not be a benzene group.

(173) In one or more embodiments, in Formula 2, when n is 1, at least one of the ring CY.sub.2 and the ring CY.sub.3 may be a) a condensed ring in which at least two first rings are condensed, b) a condensed ring in which at least two second rings are condensed, or c) a condensed ring in which at least one first ring and at least one second ring are condensed. The examples of the first ring and the second ring may be understood by referring the descriptions herein.

(174) In one or more embodiments, the second compound may include a compound represented by Formula 2(1):

(175) ##STR00096##

(176) In Formula 2(1),

(177) Ar.sub.5 may be a single bond, a C.sub.5-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.65, or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.65,

(178) Ar.sub.1, Ar.sub.2, Ar.sub.5, a1, a2, ring CY.sub.2, ring CY.sub.3, R.sub.20, R.sub.30, b2, and b3 may be the same as described above,

(179) Ar.sub.3 and Ar.sub.4 may be the same as described in connection with Ar.sub.1, and

(180) a3, a4, ring CY.sub.4, ring CY.sub.5, R.sub.40, R.sub.50, b4, and b5 may be the same as described in connection with a1, a2, ring CY.sub.2, ring CY.sub.3, R.sub.20, R.sub.30, b2, and b3.

(181) For example, Ar.sub.5 in Formula 2(1) may be a single bond.

(182) In one or more embodiments, the third compound may include a compound represented by Formula 3(1):

(183) ##STR00097##

(184) In Formula 3(1),

(185) Ar.sub.12 may be a single bond, a C.sub.5-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.65, or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.65,

(186) Het1, Ar.sub.11, R.sub.70, R.sub.80, a11, b7, b8 and m may be the same as described above,

(187) Ar.sub.3 and Ar.sub.4 may be the same as described in connection with Ar.sub.1, and

(188) Het3, Ar.sub.13, R.sub.73, R.sub.83, a13, b73, b83 and m3 may be the same as described in connection with Het1, Ar.sub.11, R.sub.70, R.sub.80, a11, b7, b8 and m.

(189) In one or more embodiments, a group represented by

(190) ##STR00098##
in Formula 2 and a group represented by

(191) ##STR00099##
and a group represented

(192) ##STR00100##
in Formula 2(1) may each independently be a group represented by one of Formulae 2-1 to 2-93:

(193) ##STR00101## ##STR00102## ##STR00103## ##STR00104## ##STR00105## ##STR00106## ##STR00107## ##STR00108## ##STR00109## ##STR00110## ##STR00111## ##STR00112## ##STR00113## ##STR00114## ##STR00115## ##STR00116##

(194) In Formulae 2-1 to 2-93,

(195) X.sub.1 may be O, S, N(R.sub.31), C(R.sub.31)(R.sub.32), or Si(R.sub.31)(R.sub.32),

(196) X.sub.2 may be O, S, N(R.sub.33), C(R.sub.33)(R.sub.34), or Si(R.sub.33)(R.sub.34),

(197) R.sub.31 to R.sub.34 are the same as described in connection with R.sub.30, and

(198) * indicates a binding site to Ar.sub.1 or Ar.sub.2 in Formula 2.

(199) In one or more embodiments, Het1 in Formula 3 and Het1 and Het3 in Formula 3(1) may each independently be a group derived from one of Formulae 3-1 to 3-40:

(200) ##STR00117## ##STR00118## ##STR00119## ##STR00120## ##STR00121##

(201) The designations a1 and a2 in Formulae 2 and 2(1) respectively indicate the number of Ar.sub.1 and the number of Ar.sub.2, and may each independently be an integer from 0 to 5 (for example, 0, 1 or 2), and the sum of a1 and a2 may be 1 or more. When a1 is 2 or more, two or more Ar.sub.1(s) may be identical to or different from each other, and when a2 is 2 or more two or more Ar.sub.2(s) may be identical to or different from each other. When a1 is 0, *—(Ar.sub.1).sub.a1—*′ in Formula 2 may be a single bond.

(202) The designations all and m in Formulae 3 and 3(1) respectively indicate the number of Ar.sub.11 and the number of *—(Ar.sub.11).sub.a11—(R.sub.70).sub.a70, and may each independently be an integer from 1 to 10. When all is 2 or more, two or more Ar.sub.11(s) may be identical to or different from each other, and when m is 2 or more, two or more *—(Ar.sub.11)a1-(R.sub.70).sub.a70 (s) may be identical to or different from each other.

(203) In one or more embodiments, all and m in Formula 3 and 3(1) may each independently be an integer from 1 to 3.

(204) R.sub.20, R.sub.30, R.sub.61, R.sub.65, R.sub.66, R.sub.70, and R.sub.80 in Formulae 2 and 3 may each independently be hydrogen, deuterium, —F, —Cl, —Br, —I, —SF.sub.5, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazino group, a hydrazono group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a substituted or unsubstituted C.sub.1-C.sub.60 alkyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkenyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkynyl group, a substituted or unsubstituted C.sub.1-C.sub.60 alkoxy group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.2-C.sub.10 heterocycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.2-C.sub.10 heterocycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryloxy group, a substituted or unsubstituted C.sub.6-C.sub.60 arylthio group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —N(Q.sub.1)(Q.sub.2), —Si(Q.sub.3)(Q.sub.4)(Q.sub.5), —Ge(Q.sub.3)(Q.sub.4)(Q.sub.5), —B(Q.sub.6)(Q.sub.7), —P(═O)(Q.sub.8)(Q.sub.9), or —P(Q.sub.8)(Q.sub.9). Q.sub.1 to Q.sub.9 are the same as described herein.

(205) For example, R.sub.20, R.sub.30, R.sub.61, R.sub.65, R.sub.66, R.sub.70, and R.sub.80 in Formulae 2 and 3 may each independently be:

(206) hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, —SF.sub.5, a C.sub.1-C.sub.20 alkyl group, or a C.sub.1-C.sub.20 alkoxy group;

(207) 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, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C.sub.1-C.sub.20 alkyl group, a deuterium-containing C.sub.1-C.sub.20 alkyl group, a fluorinated C.sub.1-C.sub.20 alkyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a bicyclo[1.1.1]pentyl group, a bicyclo[2.1.1]hexyl group, a bicyclo[2.2.1]heptyl group (a norbornyl group), a bicyclo[2.2.2]octyl group, a (C.sub.1-C.sub.20 alkyl)cyclopentyl group, a (C.sub.1-C.sub.20 alkyl)cyclohexyl group, a (C.sub.1-C.sub.20 alkyl)cycloheptyl group, a (C.sub.1-C.sub.20 alkyl)cyclooctyl group, a (C.sub.1-C.sub.20 alkyl)adamantyl group, a (C.sub.1-C.sub.20 alkyl)norbornenyl group, a (C.sub.1-C.sub.20 alkyl)cyclopentenyl group, a (C.sub.1-C.sub.20 alkyl)cyclohexenyl group, a (C.sub.1-C.sub.20 alkyl)cycloheptenyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[1.1.1]pentyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[2.1.1]hexyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[2.2.1]heptyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[2.2.2]octyl group, a silolanyl group, a phenyl group, a (C.sub.1-C.sub.20 alkyl)phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a 1,2,3,4-tetrahydronaphthyl group, a pyridinyl group, a pyrimidinyl group, or any combination thereof;

(208) a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a bicyclo[1.1.1]pentyl group, a bicyclo[2.1.1]hexyl group, a bicyclo[2.2.1]heptyl group, a bicyclo[2.2.2]octyl group, a silolanyl group, a phenyl group, a (C.sub.1-C.sub.20 alkyl)phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a 1,2,3,4-tetrahydronaphthyl 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, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl 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, or an azadibenzothiophenyl 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, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C.sub.1-C.sub.20 alkyl group, a deuterium-containing C.sub.1-C.sub.20 alkyl group, a fluorinated 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 adamantyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a bicyclo[1.1.1]pentyl group, a bicyclo[2.1.1]hexyl group, a bicyclo[2.2.1]heptyl group, a bicyclo[2.2.2]octyl group, a (C.sub.1-C.sub.20 alkyl)cyclopentyl group, a (C.sub.1-C.sub.20 alkyl)cyclohexyl group, a (C.sub.1-C.sub.20 alkyl)cycloheptyl group, a (C.sub.1-C.sub.20 alkyl)cyclooctyl group, a (C.sub.1-C.sub.20 alkyl)adamantyl group, a (C.sub.1-C.sub.20 alkyl)norbornenyl group, a (C.sub.1-C.sub.20 alkyl)cyclopentenyl group, a (C.sub.1-C.sub.20 alkyl)cyclohexenyl group, a (C.sub.1-C.sub.20 alkyl)cycloheptenyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[1.1.1]pentyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[2.1.1]hexyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[2.2.1]heptyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[2.2.2]octyl group, a silolanyl group, a phenyl group, a (C.sub.1-C.sub.20 alkyl)phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a 1,2,3,4-tetrahydronaphthyl 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, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl 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, or any combination thereof; or

(209) —N(Q.sub.1)(Q.sub.2), —Si(Q.sub.3)(Q.sub.4)(Q.sub.5), —Ge(Q.sub.3)(Q.sub.4)(Q.sub.5), —B(Q.sub.6)(Q.sub.7), —P(═O)(Q.sub.8)(Q.sub.9), or —P(Q.sub.8)(Q.sub.9),

(210) Q.sub.1 to Q.sub.9 may each independently be:

(211) —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

(212) 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, a phenyl group, a biphenyl group, or a naphthyl group, each unsubstituted or substituted with deuterium, a C.sub.1-C.sub.20 alkyl group, a phenyl group, or any combination thereof.

(213) The designations b2, b3, b7, and b8 in Formulae 2 and 3 indicate the numbers of R.sub.20, R.sub.30, R.sub.70, and R.sub.80, respectively, and may each independently be an integer from 0 to 20. For example, b2, b3, b7, and b8 may each independently be an integer from 0 to 10. When b2 is 2 or more, two or more R.sub.20(S) may be identical to or different from each other, when b3 is 2 or more, two or more R.sub.30 (s) may be identical to or different from each other, when b7 is 2 or more, two or more R.sub.70(s) may be identical to or different from each other, and when b8 is 2 or more, two or more R.sub.80(s) may be identical to or different from each other.

(214) In one or more embodiments, R.sub.20, R.sub.30, R.sub.61, R.sub.65, R.sub.66, R.sub.70 and R.sub.80 in Formulae 2 and 3 may each independently be:

(215) hydrogen or deuterium;

(216) a C.sub.1-C.sub.20 alkyl group or a C.sub.1-C.sub.20 alkoxy group, each unsubstituted or substituted with deuterium, a phenyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a triphenylenyl group, a fluorenyl group, a di(C.sub.1-C.sub.10 alkyl)fluorenyl group, a di(C.sub.6-C.sub.60 aryl)fluorenyl group, a dibenzosilolyl group, a di(C.sub.1-C.sub.10 alkyl)dibenzosilolyl group, a di(C.sub.6-C.sub.60 aryl)dibenzosilolyl group, a carbazolyl group, a (C.sub.1-C.sub.10 alkyl)carbazolyl group, a (C.sub.6-C.sub.60 aryl)carbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a biphenyl group, a terphenyl group, —N(Q.sub.31)(Q.sub.32), or any combination thereof;

(217) a π electron-rich C.sub.3-C.sub.60 cyclic group, unsubstituted or substituted with deuterium, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a triphenylenyl group, a fluorenyl group, a di(C.sub.1-C.sub.10 alkyl)fluorenyl group, a di(C.sub.6-C.sub.60 aryl)fluorenyl group, a dibenzosilolyl group, a di(C.sub.1-C.sub.10 alkyl)dibenzosilolyl group, a di(C.sub.6-C.sub.60 aryl)dibenzosilolyl group, a carbazolyl group, a (C.sub.1-C.sub.10 alkyl)carbazolyl group, a (C.sub.6-C.sub.60 aryl)carbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a biphenyl group, a terphenyl group, —N(Q.sub.31)(Q.sub.32), or any combination thereof; or —N(Q.sub.1)(Q.sub.2).

(218) Herein, Q.sub.1, Q.sub.2, Q.sub.31 and Q.sub.32 are each independently the same as described herein.

(219) In one or more embodiments, R.sub.20, R.sub.30, R.sub.61, R.sub.65, R.sub.66, R.sub.70 and R.sub.80 in Formulae 2 and 3 may each independently be:

(220) hydrogen or deuterium;

(221) a C.sub.1-C.sub.20 alkyl group unsubstituted or substituted with deuterium, a phenyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a triphenylenyl group, a fluorenyl group, a di(C.sub.1-C.sub.10 alkyl)fluorenyl group, a di(C.sub.6-C.sub.60 aryl)fluorenyl group, a dibenzosilolyl group, a di(C.sub.1-C.sub.10 alkyl)dibenzosilolyl group, a di(C.sub.6-C.sub.60 aryl)dibenzosilolyl group, a carbazolyl group, a (C.sub.1-C.sub.10 alkyl)carbazolyl group, a (C.sub.6-C.sub.60 aryl)carbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a biphenyl group, a terphenyl group, —N(Q.sub.31)(Q.sub.32), or any combination thereof; or

(222) a phenyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a triphenylenyl group, a fluorenyl group, a dibenzosilolyl group, a carbazolyl group, a dibenzofuranyl group, or a dibenzothiophenyl group, unsubstituted or substituted with deuterium, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a triphenylenyl group, a fluorenyl group, a di(C.sub.1-C.sub.10 alkyl)fluorenyl group, a di(C.sub.6-C.sub.60 aryl)fluorenyl group, a dibenzosilolyl group, a di(C.sub.1-C.sub.10 alkyl)dibenzosilolyl group, a di(C.sub.6-C.sub.60 aryl)dibenzosilolyl group, a carbazolyl group, a (C.sub.1-C.sub.10 alkyl)carbazolyl group, a (C.sub.6-C.sub.60 aryl)carbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a biphenyl group, a terphenyl group, —N(Q.sub.31)(Q.sub.32), or any combination thereof. Herein, Q.sub.31 and Q.sub.32 are each independently the same as described herein.

(223) In one or more embodiments, the second compound may include at least one of Compounds H1-1 to H1-72:

(224) ##STR00122## ##STR00123## ##STR00124## ##STR00125## ##STR00126## ##STR00127## ##STR00128## ##STR00129## ##STR00130## ##STR00131## ##STR00132## ##STR00133## ##STR00134## ##STR00135## ##STR00136## ##STR00137## ##STR00138## ##STR00139## ##STR00140## ##STR00141## ##STR00142## ##STR00143##

(225) In one or more embodiments, the third compound may include at least one of Compounds H2-1 to H2-61:

(226) ##STR00144## ##STR00145## ##STR00146## ##STR00147## ##STR00148## ##STR00149## ##STR00150## ##STR00151## ##STR00152## ##STR00153## ##STR00154## ##STR00155## ##STR00156## ##STR00157## ##STR00158## ##STR00159## ##STR00160##

(227) In one or more embodiments, the highest occupied molecular orbital (HOMO) energy level of the second compound may be −5.5 eV or more.

(228) In one or more embodiments, the lowest unoccupied molecular orbital (LUMO) energy level of the third compound may be −2.8 eV or less.

(229) An electronic device, for example, an organic light-emitting device, including the second compound and the third compound may have high external quantum efficiency (EQE) and long lifespan.

(230) In Formulae 1 to 3, 1) two or more of R.sub.1 to R.sub.8 and A.sub.20 may be optionally linked to each other to form a C.sub.5-C.sub.60 carbocyclic group which is unsubstituted or substituted with at least one R.sub.1a or a C.sub.1-C.sub.60 heterocyclic group which is unsubstituted or substituted with at least one R.sub.1a, 2) two or more of A.sub.1 to A.sub.7 may be optionally linked to each other to form a C.sub.5-C.sub.60 carbocyclic group which is unsubstituted or substituted with at least one R.sub.1a or a C.sub.1-C.sub.60 heterocyclic group which is unsubstituted or substituted with at least one R.sub.1a and 3) two or more of ring CY.sub.2, ring CY.sub.3, R.sub.20 and R.sub.30 may be optionally linked to each other to form a C.sub.5-C.sub.60 carbocyclic group which is unsubstituted or substituted with at least one R.sub.1a or a C.sub.1-C.sub.60 heterocyclic group which is unsubstituted or substituted with at least one R.sub.1a. Herein, R.sub.1a may be understood by referring to the description of A.sub.7.

(231) The term “C.sub.5-C.sub.60 carbocyclic group” as used herein refers to a saturated or unsaturated cyclic group having, as a ring-forming atom, 5 to 60 carbon atoms only. The C.sub.5-C.sub.60 carbocyclic group may be a monocyclic group or a polycyclic group.

(232) The term “a C.sub.5-C.sub.60 carbocyclic group (which is unsubstituted or substituted with at least one R.sub.1a)” may include, for example, an adamantane group, a norbornene group, a bicyclo[1.1.1]pentane group, a bicyclo[2.1.1]hexane group, a bicyclo[2.2.1]heptane group (a norbornane group), a bicyclo[2.2.2]octane group, a cyclopentane group, a cyclohexane group, a cyclohexene group, a benzene group, a naphthalene group, an anthracene group, a phenanthrene group, a triphenylene group, a pyrene group, a chrysene group, cyclopentadiene group, a fluorene group, and a 1,2,3,4-tetrahydronaphthalene group each being unsubstituted or substituted with at least one R.sub.1a.

(233) The term “C.sub.1-C.sub.60 heterocyclic group” as used herein refers to a saturated or unsaturated cyclic group having, as a ring-forming atom, at least one heteroatom of N, O, Si, P, Se, Si, B, Ge, or S other than 1 to 60 carbon atoms. The C.sub.1-C.sub.60 heterocyclic group may be a monocyclic group or a polycyclic group.

(234) The term “a C.sub.1-C.sub.60 heterocyclic group (which is unsubstituted or substituted with at least one R.sub.1a)” may include a thiophene group, a furan group, a pyrrole group, a silole group, a borole group, a phosphole group, a selenophene group, a germole group, a benzothiophene group, a benzofuran group, an indole group, an indene group, a benzosilole group, a benzoborole group, a benzophosphole group, a benzoselenophene group, a benzogermole group, a dibenzothiophene group, a dibenzofuran group, a carbazole group, a dibenzosilole group, a dibenzoborole group, a dibenzophosphole group, a dibenzoselenophene group, a dibenzogermole group, a dibenzothiophene 5-oxide group, 9H-fluorene-9-one group, a dibenzothiophene 5,5-dioxide group, an azabenzothiophene group, an azabenzofuran group, an azaindole group, an azaindene group, an azabenzosilole group, an azabenzoborole group, an azabenzophosphole group, an azabenzoselenophene group, an azabenzogermole group, an azadibenzothiophene group, an azadibenzofuran group, an azacarbazole group, an azafluorene group, an azadibenzosilole group, an azadibenzoborole group, an azadibenzophosphole group, an azadibenzoselenophene group, an azadibenzogermole group, an azadibenzothiophene 5-oxide group, an aza-9H-fluorene-9-one group, an azadibenzothiophene 5,5-dioxide 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 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 5,6,7,8-tetrahydroisoquinoline group, and a 5,6,7,8-tetrahydroquinoline group, each being unsubstituted or substituted with at least one R.sub.1a.

(235) The term “C.sub.1-C.sub.60 alkyl group” as used herein refers to a linear or branched saturated aliphatic hydrocarbon monovalent group having 1 to 60 carbon atoms, and non-limiting examples thereof include a methyl group, an ethyl group, a propyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a pentyl group, an isoamyl group, and a hexyl group. The term “C.sub.1-C.sub.60 alkylene group” used herein refers to a divalent group having the same structure as that of the C.sub.1-C.sub.60 alkyl group.

(236) Examples of the C.sub.1-C.sub.60 alkyl group, the C.sub.1-C.sub.20 alkyl group, and/or the C.sub.1-C.sub.10 alkyl group are 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 iso-nonyl group, a sec-nonyl group, a tert-nonyl group, an n-decyl group, an iso-decyl group, a sec-decyl group, and a tert-decyl group, each unsubstituted or substituted with 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 iso-nonyl group, a sec-nonyl group, a tert-nonyl group, an n-decyl group, an iso-decyl group, a sec-decyl group, a tert-decyl group, or any combination thereof. For example, Formula 9-33 may be a branched C.sub.6 alkyl group, and may be a tert-butyl group that is substituted with two methyl groups.

(237) The term “C.sub.1-C.sub.60 alkoxy group” used herein refers to a monovalent group represented by —OA.sub.101 (wherein A.sub.101 is the C.sub.1-C.sub.60 alkyl group), and examples thereof include a methoxy group, an ethoxy group, and an isopropyloxy group. Examples of the C.sub.1-C.sub.60 alkoxy group, the C.sub.1-C.sub.20 alkoxy group, or the C.sub.1-C.sub.10 alkoxy group are a methoxy group, an ethoxy group, a propoxy group, a butoxy group, or a pentoxy group.

(238) The term “C.sub.3-C.sub.10 cycloalkyl group” as used herein refers to a monovalent saturated hydrocarbon monocyclic group having 3 to 10 carbon atoms, and examples thereof include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, and a cycloheptyl group. The term “C.sub.3-C.sub.10 cycloalkylene group” as used herein refers to a divalent group having the same structure as that of the C.sub.3-C.sub.10 cycloalkyl group.

(239) Examples of the C.sub.3-C.sub.10 cycloalkyl group are a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantyl group, a bicyclo[1.1.1]pentyl group (bicyclo[1.1.1]pentyl), a bicyclo[2.1.1]hexyl group (bicyclo[2.1.1]hexyl), a bicyclo[2.2.1]heptyl group (bicyclo[2.2.1]heptyl)(a norbornyl group), and a bicyclo[2.2.2]octyl group.

(240) The term “C.sub.2-C.sub.10 heterocycloalkyl group” as used herein refers to a monovalent saturated monocyclic group having at least one heteroatom of N, O, P, Se, Si, B, Ge, or S as a ring-forming atom and 2 to 10 carbon atoms, and non-limiting examples thereof include a tetrahydrofuranyl group, and a tetrahydrothiophenyl group. The term “C.sub.2-C.sub.10 heterocycloalkylene group” as used herein refers to a divalent group having the same structure as the C.sub.2-C.sub.10 heterocycloalkyl group. Examples of the C.sub.2-C.sub.10 heterocycloalkyl group are a silolanyl group, a silinanyl group, a tetrahydrofuranyl group, a tetrahydro-2H-pyranyl group, and a tetrahydrothiophenyl group.

(241) The term “deuterium-containing C.sub.1-C.sub.60 alkyl group (or, deuterium-containing C.sub.1-C.sub.20 alkyl group, a deuterium-containing C.sub.2-C.sub.20 alkyl group, or the like)” as used herein refers to a C.sub.1-C.sub.60 alkyl group substituted with at least one deuterium (or a C.sub.1-C.sub.20 alkyl group substituted with at least one deuterium, a C.sub.2-C.sub.20 alkyl substituted with at least one deuterium, or the like). For example, the term “the deuterium-containing C.sub.1 alkyl group (that is, a deuterium-containing methyl group)” as used herein includes —CD.sub.3, —CD.sub.2H, and -CDH.sub.2.

(242) The term “deuterium-containing C.sub.3-C.sub.10 cycloalkyl group” as used herein refers to a C.sub.3-C.sub.10 cycloalkyl group substituted with at least one deuterium. Examples of the “deuterium-containing C.sub.3-C.sub.10 cycloalkyl group” are provided in connection with, for example, Formula 10-501.

(243) The terms “fluorinated C.sub.1-C.sub.60 alkyl group (or a fluorinated C.sub.1-C.sub.20 alkyl group, or the like)”, “fluorinated C.sub.3-C.sub.10 cycloalkyl group”, “fluorinated C.sub.2-C.sub.10 heterocycloalkyl group” or “fluorinated phenyl group” as used herein refer to a C.sub.1-C.sub.60 alkyl group (or, C.sub.1-C.sub.20 alkyl group, or the like) substituted with at least one a fluoro group (—F), a C.sub.3-C.sub.10 cycloalkyl group substituted with at least one a fluoro group (—F), a C.sub.2-C.sub.10 heterocycloalkyl group substituted with at least one a fluoro group (—F), and a phenyl group substituted with at least one a fluoro group (—F), respectively. For example, the term “the fluorinated C.sub.1 alkyl group (that is, the fluorinated methyl group)” includes —CF.sub.3, —CF.sub.2H, and —CFH.sub.2. The “fluorinated C.sub.1-C.sub.60 alkyl group (or the fluorinated C.sub.1-C.sub.20 alkyl group, or the like)”, “the fluorinated C.sub.3-C.sub.10 cycloalkyl group”, or “the fluorinated C.sub.2-C.sub.10 heterocycloalkyl group” may be i) a fully fluorinated C.sub.1-C.sub.60 alkyl group (or, fully fluorinated C.sub.1-C.sub.20 alkyl group, or the like), a fully fluorinated C.sub.3-C.sub.10 cycloalkyl group, or a fully fluorinated C.sub.2-C.sub.10 heterocycloalkyl group, each group in which all hydrogen are substituted with a fluoro group, or ii) a partially fluorinated C.sub.1-C.sub.60 alkyl group (or, a partially fluorinated C.sub.1-C.sub.20 alkyl group, or the like), a partially fluorinated C.sub.3-C.sub.10 cycloalkyl group, or a partially fluorinated C.sub.2-C.sub.10 heterocycloalkyl group, each group in which some hydrogen are substituted with a fluoro group.

(244) The term “(C.sub.1-C.sub.20 alkyl)‘X’ group” as used herein refers to a ‘X’ group substituted with at least one C.sub.1-C.sub.20 alkyl group. For example, the term “(C.sub.1-C.sub.20 alkyl)C.sub.3-C.sub.10 cycloalkyl group” as used herein refers to a C.sub.3-C.sub.10 cycloalkyl group substituted with at least one C.sub.1-C.sub.20 alkyl group and the term “(C.sub.1-C.sub.20 alkyl)phenyl group” as used herein refers to a phenyl group substituted with at least one C.sub.1-C.sub.20 alkyl group.

(245) The terms “an azaindole group, an azabenzoborole group, an azabenzophosphole group, an azaindene group, an azabenzosilole group, an azabenzogermole group, an azabenzothiophene group, an azabenzoselenophene group, an azabenzofuran group, an azacarbazole group, an azadibenzoborole group, an azadibenzophosphole group, an azafluorene group, an azadibenzosilole group, an azadibenzogermole group, an azadibenzothiophene group, an azadibenzoselenophene group, an azadibenzofuran group, an azadibenzothiophene 5-oxide group, an aza-9H-fluorene-9-one group, and an azadibenzothiophene 5,5-dioxide group” respectively refer to a heterocyclic group having the same backbone as “an indole group, a benzoborole group, a benzophosphole group, an indene group, a benzosilole group, a benzogermole group, a benzothiophene group, a benzoselenophene group, a benzofuran group, a carbazole group, a dibenzoborole group, a dibenzophosphole group, a fluorene group, a dibenzosilole group, a dibenzogermole group, a dibenzothiophene group, a dibenzoselenophene group, a dibenzofuran group, a dibenzothiophene 5-oxide group, 9H-fluorene-9-one group, and a dibenzothiophene 5,5-dioxide group” in which at least one carbon atoms constituting the cyclic groups is substituted with a nitrogen.

(246) The term “C.sub.2-C.sub.60 alkenyl group” as used herein refers to a hydrocarbon group formed by substituting at least one carbon-carbon double bond in the middle or at the terminus of the C.sub.2-C.sub.60 alkyl group, and examples thereof include an ethenyl group, a propenyl group, and a butenyl group. The term “C.sub.2-C.sub.60 alkenylene group” used herein refers to a divalent group having the same structure as that of the C.sub.2-C.sub.60 alkenyl group.

(247) The term “C.sub.2-C.sub.60 alkynyl group” as used herein refers to a hydrocarbon group formed by substituting at least one carbon-carbon triple bond in the middle or at the terminus of the C.sub.2-C.sub.60 alkyl group, and examples thereof include an ethynyl group, and a propynyl group. The term “C.sub.2-C.sub.60 alkynylene group” as used herein refers to a divalent group having the same structure as that of the C.sub.2-C.sub.60 alkynyl group.

(248) The term “C.sub.3-C.sub.10 cycloalkenyl group” as used herein refers to a monovalent monocyclic group that has 3 to 10 carbon atoms and at least one carbon-carbon double bond in the ring thereof and no aromaticity, and non-limiting examples thereof include a cyclopentenyl group, a cyclohexenyl group, and a cycloheptenyl group. The term “C.sub.3-C.sub.10 cycloalkenylene group” as used herein refers to a divalent group having the same structure as the C.sub.3-C.sub.10 cycloalkenyl group.

(249) The term “C.sub.2-C.sub.10 heterocycloalkenyl group” as used herein refers to a monovalent monocyclic group that has at least one heteroatom of N, O, P, Si, Se, B, Ge, or S as a ring-forming atom, 2 to 10 carbon atoms, and at least one double bond in its ring. Examples of the C.sub.2-C.sub.10 heterocycloalkenyl group are a 2,3-dihydrofuranyl group, and a 2,3-dihydrothiophenyl group. The term “C.sub.2-C.sub.10 heterocycloalkenylene group” as used herein refers to a divalent group having the same structure as the C.sub.2-C.sub.10 heterocycloalkenyl group.

(250) The term “C.sub.6-C.sub.60 aryl group” as used herein refers to a monovalent group having a carbocyclic aromatic system having 6 to 60 carbon atoms, and the term “C.sub.6-C.sub.60 arylene group” as used herein refers to a divalent group having a carbocyclic aromatic system having 6 to 60 carbon atoms. Non-limiting examples of the C.sub.6-C.sub.60 aryl group include a phenyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a pyrenyl group, and a chrysenyl group. 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 fused to each other.

(251) The term “C.sub.1-C.sub.60 heteroaryl group” as used herein refers to a monovalent group having a cyclic aromatic system that has at least one heteroatom of N, O, P, Si, Se, B, Ge, or S as a ring-forming atom, and 1 to 60 carbon atoms. The term “C.sub.1-C.sub.60 heteroarylene group” as used herein refers to a divalent group having a cyclic aromatic system that has at least one heteroatom of N, O, P, Si, Se, B, Ge, or S as a ring-forming atom, and 1 to 60 carbon atoms. Examples of the C.sub.1-C.sub.60 heteroaryl group include a pyridinyl group, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, and an isoquinolinyl group. When the C.sub.6-C.sub.60 heteroaryl group and the C.sub.6-C.sub.60 heteroarylene group each include two or more rings, the rings may be fused to each other.

(252) The term “C.sub.6-C.sub.60 aryloxy group” as used herein indicates —OA.sub.102 (wherein A.sub.102 is the C.sub.6-C.sub.60 aryl group), and the term “C.sub.6-C.sub.60 arylthio group” as used herein indicates —SA.sub.103 (wherein A.sub.103 is the C.sub.6-C.sub.60 aryl group).

(253) The term “monovalent non-aromatic condensed polycyclic group” as used 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 its entire molecular structure. Examples of the monovalent non-aromatic condensed polycyclic group include a fluorenyl group. The term “divalent non-aromatic condensed polycyclic group” as used herein refers to a divalent group having the same structure as the monovalent non-aromatic condensed polycyclic group.

(254) The term “monovalent non-aromatic condensed heteropolycyclic group” as used herein refers to a monovalent group (for example, having 2 to 60 carbon atoms) having two or more rings condensed to each other, a heteroatom of N, O, P, Si, Se, B, Ge, or S, other than carbon atoms, as a ring-forming atom, and no aromaticity in its entire molecular structure. Non-limiting examples of the monovalent non-aromatic condensed heteropolycyclic group include a carbazolyl group. The term “divalent non-aromatic condensed heteropolycyclic group” as used herein refers to a divalent group having the same structure as the monovalent non-aromatic condensed heteropolycyclic group.

(255) The term “C.sub.1-C.sub.60 cyclic group” includes the C.sub.5-C.sub.60 carbocyclic group and the C.sub.1-C.sub.60 heterocyclic group.

(256) A substituent of the substituted C.sub.5-C.sub.60 carbocyclic group, the substituted C.sub.2-C.sub.60 heterocyclic group, the substituted C.sub.1-C.sub.60 alkyl group, the substituted C.sub.2-C.sub.60 alkenyl group, the substituted C.sub.2-C.sub.60 alkynyl group, the substituted C.sub.1-C.sub.60 alkoxy group, the substituted C.sub.3-C.sub.10 cycloalkyl group, the substituted C.sub.2-C.sub.10 heterocycloalkyl group, the substituted C.sub.3-C.sub.10 cycloalkenyl group, the substituted C.sub.2-C.sub.10 heterocycloalkenyl group, the substituted C.sub.6-C.sub.60 aryl group, the substituted C.sub.6-C.sub.60 aryloxy group, the substituted C.sub.6-C.sub.60 arylthio group, the substituted C.sub.1-C.sub.60 heteroaryl group, the substituted monovalent non-aromatic condensed polycyclic group, and the substituted monovalent non-aromatic condensed heteropolycyclic group may be:

(257) 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, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, 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;

(258) 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, —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, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.2-C.sub.10 heterocycloalkyl group, a C.sub.3-C.sub.10 cycloalkenyl group, a C.sub.2-C.sub.10 heterocycloalkenyl group, a C.sub.6-C.sub.60 aryl group, a C.sub.7-C.sub.60 alkyl aryl group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.1-C.sub.60 heteroaryl group, a C.sub.2-C.sub.60 alkyl heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —N(Q.sub.11)(Q.sub.12), —Si(Q.sub.13)(Q.sub.14)(Q.sub.15), —Ge(Q.sub.13)(Q.sub.14)(Q.sub.15), —B(Q.sub.16)(Q.sub.17), —P(═O)(Q.sub.18)(Q.sub.19), —P(Q.sub.18)(Q.sub.19), or any combination thereof;

(259) a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.2-C.sub.10 heterocycloalkyl group, a C.sub.3-C.sub.10 cycloalkenyl group, a C.sub.2-C.sub.10 heterocycloalkenyl group, a C.sub.6-C.sub.60 aryl group, a C.sub.7-C.sub.60 alkylaryl group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.1-C.sub.60 heteroaryl group, a C.sub.2-C.sub.60 alkyl heteroaryl group, a monovalent non-aromatic condensed polycyclic group, or a monovalent non-aromatic condensed heteropolycyclic 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, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, 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.10 cycloalkyl group, a C.sub.2-C.sub.10 heterocycloalkyl group, a C.sub.3-C.sub.10 cycloalkenyl group, a C.sub.2-C.sub.10 heterocycloalkenyl group, a C.sub.6-C.sub.60 aryl group, a C.sub.7-C.sub.60 alkylaryl group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.1-C.sub.60 heteroaryl group, a C.sub.2-C.sub.60 alkyl heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —N(Q.sub.21) (Q.sub.22), —Si(Q.sub.23)(Q.sub.24)(Q.sub.25), —Ge(Q.sub.23)(Q.sub.24)(Q.sub.25), —B(Q.sub.26)(Q.sub.27), —P(═O)(Q.sub.28)(Q.sub.29), —P(Q.sub.28)(Q.sub.29), or any combination thereof;

(260) —N(Q.sub.31)(Q.sub.32), —Si(Q.sub.33)(Q.sub.34)(Q.sub.35), —Ge(Q.sub.33)(Q.sub.34)(Q.sub.35), —B(Q.sub.36)(Q.sub.37), —P(═O)(Q.sub.38)(Q.sub.39), or —P(Q.sub.38)(Q.sub.39); or

(261) any combination thereof.

(262) In the present specification, Q.sub.1 to Q.sub.9, Q.sub.11 to Q.sub.19, Q.sub.21 to Q.sub.29, and Q.sub.31 to Q.sub.39 may each independently be hydrogen; deuterium; —F; —Cl; —Br; —I; a hydroxyl group; a cyano group; a nitro group; an amidino group; a hydrazine group; a hydrazone group; a carboxylic acid group or a salt thereof; a sulfonic acid group or a salt thereof; a phosphoric acid group or a salt thereof; a C.sub.1-C.sub.60 alkyl group, unsubstituted or substituted with deuterium, a C.sub.1-C.sub.60 alkyl group, a C.sub.6-C.sub.60 aryl group, or any combination thereof; 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.10 cycloalkyl group; a C.sub.2-C.sub.10 heterocycloalkyl group; a C.sub.3-C.sub.10 cycloalkenyl group; a C.sub.2-C.sub.10 heterocycloalkenyl group; a C.sub.6-C.sub.60 aryl group, unsubstituted or substituted with deuterium, a C.sub.1-C.sub.60 alkyl group, a C.sub.6-C.sub.60 aryl group, or any combination thereof; a C.sub.6-C.sub.60 aryloxy group; a C.sub.6-C.sub.60 arylthio group; a C.sub.1-C.sub.60 heteroaryl group; a monovalent non-aromatic condensed polycyclic group; or a monovalent non-aromatic condensed heteropolycyclic group.

(263) For example, in the present specification, Q.sub.1 to Q.sub.9, Q.sub.11 to Q.sub.19, Q.sub.21 to Q.sub.29, and Q.sub.31 to Q.sub.39 may each independently be

(264) —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

(265) 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, a phenyl group, a biphenyl group, or a naphthyl group, each unsubstituted or substituted with deuterium, a C.sub.1-C.sub.10 alkyl group, a phenyl group, or any combination thereof.

(266) Accordingly, since the composition including the first compound, the second compound, and the third compound is suitable for use in an organic layer of an organic light-emitting device, for example, for use as a material for an emission layer in the organic layer, another aspect provides an organic light-emitting device including: a first electrode; a second electrode; and an organic layer disposed between the first electrode and the second electrode and including an emission layer, wherein the organic layer includes the composition.

(267) Due to the inclusion of the first compound, the second compound, and the third compound, the organic light-emitting device may have, a low driving voltage, high external quantum efficiency, and a long lifespan.

(268) The composition may be used between a pair of electrodes of an organic light-emitting device. For example, the composition may be included in the emission layer of the organic light-emitting device. At this time, the first compound may act as a dopant, and the second compound and third compound may each act as a host (for example, a co-host). For example, the total amount of the second compound and third compound may be greater than the amount of the first compound. The emission layer may emit red light, for example, red light having a maximum emission wavelength of 550 nm or more (for example, from 550 nm or more and 900 nm or less).

(269) The first electrode may be an anode, which is a hole injection electrode, and the second electrode may be a cathode, which is an electron injection electrode, or the first electrode may be a cathode, which is an electron injection electrode, and the second electrode may be an anode, which is a hole injection electrode.

(270) In one or more embodiments, in the organic light-emitting device, the first electrode is an anode, and the second electrode is a cathode, and the organic layer further includes 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, and the hole transport region includes a hole injection layer, a hole transport layer, an electron blocking layer, or any combination thereof, and the electron transport region includes a hole blocking layer, an electron transport layer, an electron injection layer, or any combination thereof.

(271) The term “organic layer” used herein refers to a single layer and/or a plurality of layers between the first electrode and the second electrode of the organic light-emitting device. The “organic layer” may include, in addition to an organic compound, an organometallic complex including metal.

(272) FIGURE is a schematic view of an organic light-emitting device 10 according to one embodiment. Hereinafter, the structure of an organic light-emitting device according to an embodiment and a method of manufacturing an organic light-emitting device according to an embodiment will be described in connection with FIGURE. The organic light-emitting device 10 includes a first electrode 11, an organic layer 15, and a second electrode 19, which are sequentially stacked.

(273) A substrate may be additionally located under the first electrode 11 or above the second electrode 19. For use as the substrate, any substrate that is used in organic light-emitting devices may be used, and the substrate may be a glass substrate or a transparent plastic substrate, each having excellent mechanical strength, thermal stability, transparency, surface smoothness, ease of handling, and water resistance.

(274) In one or more embodiments, the first electrode 11 may be formed by depositing or sputtering a material for forming the first electrode 11 on the substrate. The first electrode 11 may be an anode. The material for forming the first electrode 11 may be of materials with a high work function to facilitate hole injection. The first electrode 11 may be a reflective electrode, a semi-transmissive electrode, or a transmissive electrode. The material for forming the first electrode 11 may be indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO.sub.2), or zinc oxide (ZnO). In one or more embodiments, the material for forming the first electrode 11 may be metal, such as magnesium (Mg), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), or magnesium-silver (Mg—Ag).

(275) The first electrode 11 may have a single-layered structure or a multi-layered structure including two or more layers. For example, the first electrode 11 may have a three-layered structure of ITO/Ag/ITO, but the structure of the first electrode 11 is not limited thereto.

(276) The organic layer 15 is located on the first electrode 11.

(277) The organic layer 15 may include a hole transport region, an emission layer, and an electron transport region.

(278) The hole transport region may be between the first electrode 11 and the emission layer.

(279) The hole transport region may include a hole injection layer, a hole transport layer, an electron blocking layer, a buffer layer, or any combination thereof.

(280) The hole transport region may include only either a hole injection layer or a hole transport layer. In one or more embodiments, the hole transport region may have a hole injection layer/hole transport layer structure or a hole injection layer/hole transport layer/electron blocking layer structure, which are sequentially stacked in this stated order from the first electrode 11.

(281) When the hole transport region includes a hole injection layer (HIL), the hole injection layer may be formed on the first electrode 11 by using one or more suitable methods, for example, vacuum deposition, spin coating, casting, and/or Langmuir-Blodgett (LB) deposition.

(282) When a hole injection layer is formed by vacuum deposition, the deposition conditions may vary according to a material that is used to form the hole injection layer, and the structure and thermal characteristics of the hole injection layer. For example, the deposition conditions may include a deposition temperature of about 100° C. to about 5000C, a vacuum pressure of about 10.sup.−8 torr to about 10.sup.−3 torr, and a deposition rate of about 0.01 Å/sec to about 100 Å/sec. However, the deposition conditions are not limited thereto.

(283) When the hole injection layer is formed using spin coating, coating conditions may vary according to the material used to form the hole injection layer, and the structure and thermal properties of the hole injection layer. For example, a coating speed may be from about 2,000 rpm to about 5,000 rpm, and a temperature at which a heat treatment is performed to remove a solvent after coating may be from about 80° C. to about 200° C. However, the coating conditions are not limited thereto.

(284) Conditions for forming a hole transport layer and an electron blocking layer may be understood by referring to conditions for forming the hole injection layer.

(285) The hole transport region may include m-MTDATA, TDATA, 2-TNATA, NPB, β-NPB, TPD, Spiro-TPD, Spiro-NPB, methylated-NPB, TAPC, 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), a compound represented by Formula 201 below, a compound represented by Formula 202 below, or any combination thereof:

(286) ##STR00161## ##STR00162## ##STR00163## ##STR00164##

(287) Ar.sub.101 and Ar.sub.102 in Formula 201 may each independently be a phenylene group, a pentalenylene group, an indenylene group, a naphthylene group, an azulenylene group, a heptalenylene group, an acenaphthylene group, a fluorenylene group, a phenalenylene group, a phenanthrenylene group, an anthracenylene group, a fluoranthenylene group, a triphenylenylene group, a pyrenylene group, a chrysenylenylene group, a naphthacenylene group, a picenylene group, a perylenylene group, or a pentacenylene group, each unsubstituted or substituted with deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, 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.10 cycloalkyl group, a C.sub.3-C.sub.10 cycloalkenyl group, a C.sub.2-C.sub.10 heterocycloalkyl group, a C.sub.2-C.sub.10 heterocycloalkenyl group, a C.sub.6-C.sub.60 aryl group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.1-C.sub.60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, or any combination thereof.

(288) The designations xa and xb in Formula 201 may each independently be an integer from 0 to 5, or 0, 1 or 2. For example, xa may be 1 and xb may be 0, but xa and xb are not limited thereto.

(289) R.sub.101 to R.sub.108, R.sub.111 to R.sub.119 and R.sub.121 to R.sub.124 in Formulae 201 and 202 may each independently be:

(290) hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C.sub.1-C.sub.10 alkyl group (for example, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, or a hexyl group), or a C.sub.1-C.sub.10 alkoxy group (for example, a methoxy group, an ethoxy group, a propoxy group, a butoxy group, or a pentoxy group);

(291) a C.sub.1-C.sub.10 alkyl group or a C.sub.1-C.sub.10 alkoxy group, each unsubstituted or substituted with deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, or any combination thereof; or

(292) a phenyl group, a naphthyl group, an anthracenyl group, a fluorenyl group, or a pyrenyl group, each unsubstituted or substituted with deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C.sub.1-C.sub.10 alkyl group, a C.sub.1-C.sub.10 alkoxy group, or any combination thereof.

(293) R.sub.109 in Formula 201 may be a phenyl group, a naphthyl group, an anthracenyl group, or a pyridinyl group, each unsubstituted or substituted with deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a naphthyl group, an anthracenyl group, a pyridinyl group, or any combination thereof.

(294) In one or more embodiments, the compound represented by Formula 201 may be represented by Formula 201A below:

(295) ##STR00165##

(296) R.sub.101, R.sub.111, R.sub.112, and R.sub.109 in Formula 201A may be understood by referring to the description provided herein.

(297) For example, the hole transport region may include at least one of compounds HT1 to HT20 illustrated below, but are not limited thereto:

(298) ##STR00166## ##STR00167## ##STR00168## ##STR00169## ##STR00170## ##STR00171##

(299) The thickness of the hole transport region may be in a range of about 100 Å to about 10,000 Å, for example, about 100 Å to about 1,000 Å. 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 Å to about 10,000 Å, for example, about 100 Å to about 1,000 Å, and a thickness of the hole transport layer may be in a range of about 50 Å to about 2,000 Å, for example about 100 Å to about 1,500 Å. 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.

(300) The hole transport region may further include, in addition to these materials, a charge-generation material for the improvement of conductive properties. The charge-generation material may be homogeneously or non-homogeneously dispersed in the hole transport region.

(301) The charge-generation material may be, for example, a p-dopant. The p-dopant may be a quinone derivative, a metal oxide, a cyano group-containing compound, or any combination thereof, but embodiments of the present disclosure are not limited thereto. Examples of the p-dopant are a quinone derivative, such as tetracyanoquinodimethane (TCNQ), 2,3,5,6-tetrafluoro-tetracyano-1,4-benzoquinone dimethane (F4-TCNQ), or F6-TCNNQ; a metal oxide, such as a tungsten oxide or a molybdenum oxide; a cyano group-containing compound, such as Compound HT-D1 below; or any combination thereof.

(302) ##STR00172##

(303) The hole transport region may include a buffer layer.

(304) Also, the buffer layer may compensate for an optical resonance distance according to a wavelength of light emitted from the emission layer, and thus, efficiency of a formed organic light-emitting device may be improved.

(305) Meanwhile, when the hole transport region includes an electron blocking layer, a material for the electron blocking layer may be a material for the hole transport region described above, a material for a host to be explained later, or any combination thereof. For example, when the hole transport region includes an electron blocking layer, a material for the electron blocking layer may be mCP.

(306) Then, an emission layer (EML) may be formed on the hole transport region by vacuum deposition, spin coating, casting, LB deposition, or the like. When the emission layer is formed by vacuum deposition or spin coating, the deposition or coating conditions may be similar to those applied in forming the hole injection layer although the deposition or coating conditions may vary according to a material that is used to form the hole transport layer.

(307) The emission layer may include the composition including the first compound through the third compound as described herein.

(308) In one or more embodiments, the emission layer may include a host and a dopant, the dopant may include the first compound, and the host may include the second compound and the third compound.

(309) The weight ratio of the second compound to the third compound may be from 1:9 to 9:1, from 2:8 to 8:2, from 3:7 to 7:3, or from 4:6 to from 6:4. In one or more embodiments, the weight ratio of the second compound and the third compound may be 5:5, but embodiments are not limited.

(310) Meanwhile, the emission layer may further include any dopant and/or host in addition to the composition described herein.

(311) When the organic light-emitting device is a full-color organic light-emitting device, the emission layer may be patterned into a red emission layer, a green emission layer, and/or a blue emission layer. In one or more embodiments, due to a stacked structure including a red emission layer, a green emission layer, and/or a blue emission layer, the emission layer may emit white light.

(312) When the emission layer includes a host and a dopant, an amount of the dopant 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, but embodiments of the present disclosure are not limited thereto.

(313) A thickness of the emission layer may be in a range of about 100 Å to about 1,000 Å, for example, about 200 Å to about 600 Å. When the thickness of the emission layer is within this range, excellent light-emission characteristics may be obtained without a substantial increase in driving voltage.

(314) Then, an electron transport region may be disposed on the emission layer.

(315) The electron transport region may include a hole blocking layer, an electron transport layer, an electron injection layer, or any combination thereof.

(316) For example, the electron transport region may have a hole blocking layer/electron transport layer/electron injection layer structure or an electron transport layer/electron injection layer structure, but the structure of the electron transport region is not limited thereto. The electron transport layer may have a single-layered structure or a multi-layered structure including two or more different materials.

(317) Conditions for forming the hole blocking layer, the electron transport layer, and the electron injection layer which constitute the electron transport region may be understood by referring to the conditions for forming the hole injection layer.

(318) When the electron transport region includes a hole blocking layer, the hole blocking layer may include, for example, at least one of BCP, Bphen, and BAlq.

(319) ##STR00173##

(320) The thickness of the hole blocking layer may be in a range of about 20 Å to about 1,000 Å, for example, about 30 Å to about 300 Å. When the thickness of the hole blocking layer is within these ranges, the hole blocking layer may have excellent hole blocking characteristics without a substantial increase in driving voltage.

(321) The electron transport layer may include BCP, Bphen, TPBi, Alq.sub.3, Balq, TAZ, NTAZ, or any combination thereof.

(322) ##STR00174##

(323) In one or more embodiments, the electron transport layer may include at least one of ET1 to ET25:

(324) ##STR00175## ##STR00176## ##STR00177## ##STR00178## ##STR00179## ##STR00180## ##STR00181## ##STR00182## ##STR00183##

(325) The thickness of the electron transport layer may be in a range of about 100 Å to about 1,000 Å, for example, about 150 Å to about 500 Å. When the thickness of the electron transport layer is within the range described above, the electron transport layer may have satisfactory electron transport characteristics without a substantial increase in driving voltage.

(326) Also, the electron transport layer may further include, in addition to the materials described above, a metal-containing material.

(327) The metal-containing material may include a Li complex. The Li complex may include, for example, Compound ET-D1, ET-D2, or a combination thereof.

(328) ##STR00184##

(329) The electron transport region may include an electron injection layer (EIL) that promotes flow of electrons from the second electrode 19 thereinto.

(330) The electron injection layer may include LiF, NaCl, CsF, Li.sub.2O, BaO, or any combination thereof.

(331) The thickness of the electron injection layer may be in a range of about 1 Å to about 100 Å, and, for example, about 3 Å to about 90 Å. When the thickness of the electron injection layer is within the range described above, the electron injection layer may have satisfactory electron injection characteristics without a substantial increase in driving voltage.

(332) The second electrode 19 is located on the organic layer 15. The second electrode 19 may be a cathode. A material for forming the second electrode 19 may be metal, an alloy, an electrically conductive compound, or a combination thereof, which have a relatively low work function. For example, lithium (Li), magnesium (Mg), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), or magnesium-silver (Mg—Ag) may be formed as the material for forming the second electrode 19. To manufacture a top-emission type light-emitting device, a transmissive electrode formed using ITO or IZO may be used as the second electrode 19.

(333) Hereinbefore, the organic light-emitting device has been described with reference to FIGURE, but embodiments of the present disclosure are not limited thereto.

(334) Hereinafter, a compound and an organic light-emitting device according to embodiments are described in detail with reference to Synthesis Example and Examples. However, the organic light-emitting device is not limited thereto. The wording “B was used instead of A” used in describing Synthesis Examples means that an amount of A used was identical to an amount of B used, in terms of a molar equivalent.

EXAMPLES

Synthesis Example 1 (Compound 3)

(335) ##STR00185##

Synthesis of Intermediate L3-2

(336) 2.5 g (9.3 mmol) of 2-chloro-4-iodo-nicotinaldehyde was mixed with 100 ml of tetrahydrofuran and 30 ml of water, and 0.53 g (0.46 mmol) of Pd(PPh.sub.3).sub.4, 1.3 g (9.3 mmol) of 3-fluorophenylboronic acid, and 3.2 g (23.0 mmol) of K.sub.2CO.sub.3 were added to the mixture, followed by heating at a temperature of 80° C. for 24 hours while refluxing. When the reaction was completed, the reaction mixture was concentrated under reduced pressure, dichloromethane and water were added thereto, and an extraction process was performed thereon to obtain an organic layer. The organic layer was dried by using magnesium sulfate, distilled under reduced pressure, and purified by column chromatography to obtain 1.1 g of Intermediate L3-2 (yield of 51%).

(337) LCMS: m/z calcd for C.sub.12H.sub.7ClFNO 235.02; Found 236.06.

Synthesis of Intermediate L3-1

(338) 5.8 g (17.0 mmol) of (methoxymethyl)triphenylphosphonium chloride and 1.6 g (6.8 mmol) of Intermediate L3-2 were added to 50 ml of tetrahydrofuran and mixed together, and then, 17 ml of 1.0 M potassium tert-butoxide solution (in THF) was slowly added dropwise thereto at room temperature and mixed for 24 hours. When the reaction was completed, the organic layer, obtained by adding water and ethyl acetate to the reaction mixture and performing an extraction process thereon, was dried by using magnesium sulfate and distilled under reduced pressure. The resulting product was dried under reduced pressure, and then, mixed with 40 ml of dichloromethane, and then, 1.5 ml of methanesulfonic acid was slowly added dropwise thereto at room temperature, followed by stirring at room temperature for about 12 hours. When the reaction was completed, an organic layer, obtained by adding saturated aqueous sodium hydrogen carbonate solution and performing an extraction process thereon, was dried by using magnesium sulfate, distilled under reduced pressure, and purified by column chromatography to obtain 1.1 g of Intermediate L3-1 (yield of 72%).

(339) LCMS: m/z calcd for C.sub.12H.sub.7ClFNO 235.02; Found 236.06.

Synthesis of Intermediate L3

(340) 0.7 g (3.0 mmol) of Intermediate L3-1 was mixed with 30 ml of THF and 10 ml of water, and 0.5 g (3.6 mmol) of 3,5-dimethylphenylboronic acid, 0.24 g (0.2 mmol) of Pd(PPh.sub.3).sub.4, and 1.0 g (7.5 mmol) of K.sub.2CO.sub.3 were added thereto, and the mixture was heated while refluxing for 24 hours. When the reaction was completed, an organic layer, obtained by adding ethyl acetate and water and performing an extraction process thereon, was dried by using magnesium sulfate, distilled under reduced pressure, and purified by column chromatography to obtain 0.72 g of Intermediate L3 (yield 80%).

(341) LCMS: m/z calcd for C.sub.21H.sub.16FN 301.13; Found 302.05.

Synthesis of Intermediate L3 Dimer

(342) 40 mL of ethoxyethanol and 15 mL of distilled water were mixed with 1.05 g (3.4 mmol) of Intermediate L3 and 0.6 g (1.6 mmol) of iridium chloride, and then, the mixture was heated while refluxing for 24 hours. When the reaction was completed, the temperature was lowered to room temperature, and the solid produced therefrom was filtered and washed sufficiently in the order of water/methanol/hexane. The solid obtained was dried in a vacuum oven to obtain 1.0 g of Intermediate L3 Dimer.

Synthesis of Compound 3

(343) 1.0 g (0.63 mmol) of Intermediate L3 Dimer, 0.96 g (4.5 mmol) of 3,7-diethylnonane-4,6-dione, and 0.48 g (4.5 mmol) of Na.sub.2CO.sub.3 were mixed with 40 mL of ethoxyethanol, and then, the mixture was stirred for 24 hours at a temperature of 90° C. When the reaction was completed, the temperature was lowered to room temperature, and the solid produced therefrom was filtered and purified by liquid chromatography to obtain 0.8 g of Compound 3 (yield of 65%).

(344) LCMS: m/z calcd for C.sub.55H.sub.53F.sub.2IrN.sub.2O.sub.2, 1004.37; Found 1005.25.

Synthesis Example 2 (Compound 9)

(345) ##STR00186##

Synthesis of Intermediate L9

(346) Intermediate L9 was synthesized in the same manner as used in synthesizing Intermediate L3 in Synthesis Example 1, except that Intermediate L9-1 was used instead of Intermediate L3-1.

(347) LC-MS m/z=303(M+H).sup.+

Synthesis of Intermediate L9 Dimer

(348) Intermediate L9 Dimer was synthesized in the same manner as used in synthesizing Intermediate L3 Dimer in Synthesis Example 1, except that Intermediate L9 was used instead of Intermediate L3.

Synthesis of Compound 9

(349) Compound 9 was synthesized in the same manner as used to synthesize Compound 3 of Synthesis Example 1, except that Intermediate L9 Dimer and 3,7-diethyl-3,7-dimethylnonane-4,6-dione were used instead of Intermediate L3 Dimer and 3,7-diethylnonane-4,6-dione.

(350) LC-MS m/z=1035(M+H).sup.+

Synthesis Example 3 (Compound 10)

(351) ##STR00187##

Synthesis of Intermediate L10

(352) Intermediate L10 was synthesized in the same manner as used in synthesizing Intermediate L3 in Synthesis Example 1, except that Intermediate L10-1 was used instead of Intermediate L3-1.

(353) LCMS: m/z calcd for C.sub.22H.sub.16F.sub.3N 351.36; Found 352.21.

Synthesis of Intermediate L10 Dimer

(354) Intermediate L10 Dimer was synthesized in the same manner as used in synthesizing Intermediate L3 Dimer in Synthesis Example 1, except that Intermediate L10 was used instead of Intermediate L3.

Synthesis of Compound 10

(355) Compound 10 was synthesized in the same manner as used to synthesize Compound 3 of Synthesis Example 1, except that Intermediate L10 Dimer was used instead of Intermediate L3 Dimer.

(356) LCMS: m/z calcd for C.sub.57H.sub.53F.sub.6IrN.sub.2O.sub.2 1104.35; Found 1105.40.

Example 1

(357) A glass substrate with ITO/Ag/ITO deposited thereon as an anode with a thickness of 70/1000/70 Å thereon, which was manufactured by Corning Inc., was cut to a size of 50 mm×50 mm×0.5 mm, and the glass substrate was sonicated by using isopropyl alcohol and pure water for 5 minutes each, and then ultraviolet (UV) light was irradiated for 30 minutes thereto and ozone was exposed thereto for cleaning. Then, the resultant glass substrate was loaded onto a vacuum deposition apparatus.

(358) On the anode, 2-TNATA was vacuum deposited to form a hole injection layer having a thickness of 600 Å, and 4,4′-bis[N-(1-naphthyl)-N-phenylamino] biphenyl (hereinafter referred to as NPB) was vacuum-deposited on the hole injection layer to form a hole transport layer having a thickness of 1350 Å.

(359) Then, a host (the mixture of Compound H1-14 and Compound H2-6 (the weight ratio of 5:5)) and a dopant (Compound 3) were co-deposited on the hole transport layer at a weight ratio of 98:2 to form an emission layer having a thickness of 400 Å.

(360) Then, BCP was vacuum-deposited on the emission layer to form a hole blocking layer having a thickness of 50 Å and then, Alq.sub.3 was vacuum-deposited on the hole blocking layer to form an electron transport layer having a thickness of 350 Å, and then, LiF was vacuum-deposited on the electron transport layer to form an electron injection layer having a thickness of 10 Å, and Mg and Ag were co-deposited on the electron injection layer at the weight ratio of 90:10 to form a cathode having a thickness of 120 Å, thereby completing the manufacture of an organic light-emitting device (emission of red light).

(361) ##STR00188##

Examples 2 to 3 and Comparative Example 1

(362) Organic light-emitting devices were manufactured in the same manner as in Example 1, except that in forming an emission layer, for use as a dopant, corresponding compounds shown in Table 1 were used instead of Compound 3.

(363) Evaluation Example 1: Evaluation on characteristics of organic light-emitting device With respect to each of the organic light-emitting devices manufactured according to Examples 1 to 3 and Comparative Example 1, the driving voltage, current density, maximum of external quantum efficiency (Max EQE), FWHM of EL spectrum, emission color, color coordinate, and lifespan (LT.sub.97) were evaluated. Results thereof are shown in Table 1. This evaluation was performed using a current-voltage meter (Keithley 2400) and a luminescence meter (Minolta Cs-1,000A), and the lifespan (LT.sub.97)(at 3500 nit) was evaluated by measuring the amount of time that elapsed until luminance was reduced to 97% of the initial brightness of 100%. Lifespan (LT.sub.97) is expressed as a relative value (%) to the lifespan of Comparative Example 1.

(364) TABLE-US-00001 TABLE 1 Host Dopant Driving Current Max Color LT.sub.97 compound compound Voltage density EQE FWHM Emission coordinates (Relative No. No. Voltage (V) (mA/cm.sup.2) (%) (nm) color (ClEx) value, %) Example 1 H1-14 H2-6 3 3.61 11.1 31.1 46.34 red 0.675, 113 Weight ratio of 5:5 0.324 Example 2 H1-14 H2-6 9 3.6 12.1 31 46.2 red 0.678, 125 Weight ratio of 5:5 0.321 Example 3 H1-14 H2-6 10 4.06 12.9 30.5 47.16 red 0.678, 102 Weight ratio of 5:5 0.321 Comparative H1-14 H2-6 A 4.12 15.5 28.8 47.07 red 0.680, 100 Example 1 Weight ratio of 5:5 0.318 0

(365) From Table 1, it was confirmed that the organic light-emitting devices of Example 1 to 3 have improved characteristics compared to the organic light-emitting device of Comparative Example 1 in terms of the driving voltage, external quantum efficiency, and lifespan.

(366) The composition has excellent electrical properties and stability. Accordingly, an electronic device, for example, an organic light-emitting device using the composition may have improved characteristics in terms of the driving voltage, external quantum efficiency, and lifespan.

(367) 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 FIGURES, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope as defined by the following claims.