An organometallic compound, represented by Formula 1:

##STR00001## wherein M.sub.1 is a transition metal; X.sub.10 is C; X.sub.11 to X.sub.14, X.sub.20, X.sub.30 to X.sub.36, and X.sub.40 are each independently C or N; ring A.sub.20 and ring A.sub.40 are each independently a C.sub.5-C.sub.30 carbocyclic group or a C.sub.1-C.sub.30 heterocyclic group; and R.sub.1 to R.sub.5, R.sub.10, R.sub.20, R.sub.31, R.sub.32, R.sub.40, R.sub.51, R.sub.52, T.sub.1, b10, b20, b31, b32, and b40 are as defined herein.

An organic light emitting device (OLED) that includes an anode, a cathode, and an organic layer disposed between the anode and the cathode. The organic layer includes a metal compound that comprises a ligand L.sub.A of Formula I, wherein the dashed lines represent coordination to a metal M. ##STR00001##
The metal M is selected from the groups consisting of Os, Ru, Ir, Rh, Pt, Pd, and Cu, and the metal is further coordinated to one or more ligand(s) L.sub.B, wherein the ligand(s) L.sub.B can be the same or different if more than one ligand L.sub.B is present. Optionally one or two of the ligand(s) L.sub.B can independently link to the ligand L.sub.A through one of R.sup.1 to R.sup.5. The invention is also directed to a consumer product that includes an OLED, and the OLED includes an organic layer that includes a metal compound that comprises a ligand L.sub.A of Formula I.

A compound comprising a first ligand L.sub.A of Formula I or Formula II: ##STR00001## wherein A.sup.1 and A.sup.2 are each independently C or Si; wherein each R.sup.A, and R.sup.B independently represents mono to the maximum allowable substitution, or no substitution; wherein each X.sup.1, X.sup.2, and X.sup.3 is independently C or N; wherein each R, R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.A is independently a hydrogen or a substituent selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, boryl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof; wherein L.sub.A is complexed to a metal M; wherein M is optionally coordinated to one or more other ligands; wherein the ligand L.sub.A is optionally linked with the one or more other ligands to form a tridentate, tetradentate, pentadentate, or hexadentate ligand; and wherein any two substituents are optionally joined or fused together to form a ring.

To provide an organic electroluminescent device having high efficiency and high driving stability while having a low driving voltage. The organic electroluminescent device has one or more light-emitting layers between an anode and a cathode opposed to each other, wherein at least one of the light-emitting layers is a light-emitting layer composed of a vapor deposition layer containing a first host, a second host and a light-emitting dopant material; the first host is selected from oligopyridine compounds represented by the general formula (1); and the second host is selected from carbazole compounds having two or more carbazole rings, indolocarbazole compounds having an indolocarbazole ring or compounds having a carbazole ring and an indolocarbazole ring.

An organic electroluminescence device includes: a first electrode; a hole transport region disposed on the first electrode; an emission layer disposed on the hole transport region; an electron transport region disposed on the emission layer; and a second electrode disposed on the electron transport region, wherein the emission layer includes an organometallic compound of Formula 1:

##STR00001##

wherein, in Formula 1, the variables are described herein.

Platinum complex of the type [L1L2Pt[O(CO)R1]X].sub.n, wherein L1 and L2 are the same or different monoolefin ligands or together represent a compound L1L2 acting as a diolefin ligand, wherein X is selected from bromide, chloride, iodide, and —O(CO)R2, wherein —O(CO)R1 and —O(CO)R2 are the same or different C6-C18 or C8-C18 non-aromatic monocarboxylic acid groups with the exception of a phenylacetic acid group, or together represent a C8-C18 non-aromatic dicarboxylic acid group —O(CO)R1R2(CO)O—, wherein it is a mononuclear platinum complex where n=1, or wherein, in the event of the presence of L1L2 and/or of —O(CO)R1R2(CO)O—, it may be a polynuclear platinum complex with a whole number n>1.

Provided are compounds comprising ligands L.sub.A that are ligands of Pt and Ir complexes for OLED applications. Also provided are formulations comprising these compounds comprising ligands L.sub.A that are ligands of Pt and Ir complexes for OLED applications. Further provided are OLEDs and related consumer products that utilize these compounds comprising ligands L.sub.A that are ligands of Pt and Ir complexes for OLED applications.

A light-emitting device includes: a first electrode; a second electrode facing the first electrode; and an interlayer between the first electrode and the second electrode and including an emission layer, wherein the interlayer includes a heterocyclic compound of Formula 1:

A.sub.1B.sub.1].sub.n1  Formula 1

wherein, in Formula 1, the variables are defined herein.

Provided are compounds comprising anionic bidentate ligands L.sub.A that are ligands of Pt and Ir complexes for OLED applications. Also provided are formulations comprising these compounds comprising anionic bidentate ligands L.sub.A that are ligands of Pt and Ir complexes for OLED applications. Further provided are OLEDs and related consumer products that utilize these compounds comprising anionic bidentate ligands L.sub.A that are ligands of Pt and Ir complexes for OLED applications.

A composition comprising a first compound, a second compound, and a third compound, wherein the first compound, the second compound, and the third compound are different from each other, the first compound satisfies one of Condition 1 and Condition 2 as described herein, and the second compound includes a compound represented by Formula 1:

##STR00001##

wherein ring A.sub.1 is a condensed cyclic group in which 3 or more cyclic groups are condensed with each other, and the 3 or more cyclic groups are each a C.sub.5-C.sub.30 carbocyclic group or a C.sub.1-C.sub.30 heterocyclic group; a1 is an integer from 1 to 5; b1 is an integer from 3 to 10; and L.sub.1, R.sub.1, and R.sub.2 are as described herein.