ORGANIC ELECTROLUMINESCENT MATERIALS AND DEVICES

1 . A compound having a metal coordination complex structure:

wherein the compound is capable of functioning as a phosphorescent emitter in an organic light emitting device at room temperature:

wherein the compound has a first bidentate ligand coordinated to a metal:

wherein the first bidentate ligand comprises a first benzene ring coordinated to the metal;

wherein the first benzene ring is fused with a second aromatic ring:

wherein the second aromatic ring is fused with a third aromatic ring:

wherein the metal is iridium; and

wherein the compound has a triplet emission spectrum with a full width at half maximum (FWHM) value of no more than 45 nm at 22° C.

2 . The compound of claim 1 , wherein the compound has a triplet emission spectrum with a FWHM value of no more than 40 nm at 22° C.

3 . The compound of claim 1 , wherein the compound has a triplet emission spectrum with a FWHM value of no more than 35 nm at 22° C.

4 . The compound of claim 1 , wherein the compound has a metal-carbon bond.

5 . The compound of claim 1 , wherein the second aromatic ring is a five-membered ring.

6 . The compound of claim 1 , wherein the third aromatic ring is fused with a fourth aromatic ring.

7 . The compound of claim 1 , wherein the compound comprises a pyridine ring coordinated to the metal.

8 . The compound of claim 7 , wherein the pyridine ring is substituted with at least one group selected from the group consisting of alkyl, cycloalkyl, fully or partially deuterated variants thereof, and combination thereof.

9 . The compound of claim 1 , wherein the compound has a formula of M(L A ) x (L B ) y (L C ) z wherein M is Ir, L B is the first bidentate ligand, and L A and L C are each a bidentate ligand; and wherein x is 1 or 2; y is 1, or 2; z is 0, or 1; and x+y+z is the oxidation state of the metal M.

10 . The compound of claim 9 , wherein the compound has the formula of Ir(L A ) 2 (L B ).

11 . The compound of claim 9 , wherein L A and L C are each independently selected from the group consisting of:

wherein each X 1 to X 13 are independently selected from the group consisting of carbon and nitrogen;

wherein X is selected from the group consisting of BR′, NR′, PR′, O, S, Se, C═O, S═O, SO 2 , CR′R″, SiR′R″, and GeR′R″;

wherein R′and R″ are optionally fused or joined to form a ring;

wherein each R a , R b , R c , and R d may represent from mono substitution to the maximum possible number of substitution, or no substitution;

wherein R′, R″, R a , R b , R c , and R d are each independently selected from the group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof, and wherein any two adjacent substituents of R a , R b , R c , and R d are optionally fused or joined to form a ring or form a multidentate ligand.

12 . The compound of claim 11 , wherein L A has the formula:

13 . The compound of claim 12 , wherein L A has the formula:

14 . The compound of claim 9 , wherein L B has a formula of:

wherein each X 1 to X 9 are independently selected from the group consisting of carbon and nitrogen;

wherein X is selected from the group consisting of BR′, NR′, PR′, O, S, Se, C═O, S═O, SO 2 , CR′R″, SiR′R″, and GeR′R″;

wherein R′ and R″ are optionally fused or joined to form a ring;

wherein each R a , R b , and R c independently represent from mono substitution to the maximum possible number of substitution, or no substitution;

wherein R′, R″, R a , R b , and R c are each independently selected from the group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof;

wherein any two adjacent R a , or R b are optionally fused or joined to form a ring or form a multidentate ligand; and

wherein two Re are joined to form a ring structure comprising three or more fused aromatic rings.

15 . The compound of claim 14 , wherein R a , or R b , or R c is each independently selected from the group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, arylalkyl, amino, silyl, aryl, heteroaryl, ester, nitrile, isonitrile, and combinations thereof.

16 . The compound of claim 15 , wherein one of R a , R b , or R c is selected from the group consisting of deuterium, halide, alkyl, cycloalkyl, silyl, aryl, heteroaryl, nitrile, and combinations thereof.

17 . The compound of claim 14 , wherein L B has a formula selected from the group consisting of:

18 . An organic light emitting device (OLED) comprising:

an anode;

a cathode; and an organic layer, disposed between the anode and the cathode, comprising a compound having a metal coordination complex structure;

wherein the compound is capable of functioning as a phosphorescent emitter in an organic light emitting device at room temperature;

wherein the compound has a first bidentate ligand coordinated to a metal;

wherein the first bidentate ligand comprises a first benzene ring coordinated to the metal;

wherein the first benzene ring is fused with a second aromatic ring;

wherein the second aromatic ring is fused with a third aromatic ring;

wherein the metal is iridium; and

wherein the compound has a triplet emission spectrum with a full width at half maximum (FWHM) value of no more than 45 nm at 22° C.

19 . A consumer product comprising an organic light-emitting device (OLED) comprising:

an anode;

a cathode; and

an organic layer, disposed between the anode and the cathode, comprising a compound having a metal coordination complex structure;

wherein the compound is capable of functioning as a phosphorescent emitter in an organic light emitting device at room temperature;

wherein the compound has a first bidentate ligand coordinated to a metal;

wherein the first bidentate ligand comprises a first benzene ring coordinated to the metal;

wherein the first benzene ring is fused with a second aromatic ring;

wherein the second aromatic ring is fused with a third aromatic ring;

wherein the metal is iridium; and

wherein the compound has a triplet emission spectrum with a full width at half maximum (FWHM) value of no more than 45 nm at 22° C.

20 . A formulation comprising a compound according to claim 1 .