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 formula of Pt(L A )(L B ), wherein L A and L B are each independently selected from the group consisting of:

wherein L A and L B may be joined to form a tetradentate ligand;

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 tetradentate ligand;

wherein a free-state of ligand L A or a tetradentate ligand when L A and L B are joined together has a first triplet energy T1 of E L at 77K;

wherein the compound has a first triplet energy T1 of E at 77K;

wherein the difference in energy between E and E L is ΔE;

wherein ΔE is ≤250 meV; 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 ΔE is ≤200 meV.

3. The compound of claim 1 , wherein the compound has a triplet emission spectrum with a FWHM value of no more than 40 nm.

4. The compound of claim 1 , wherein L A and L B are each independently selected from the group consisting of:

5. The compound of claim 1 , wherein L A and L B are each independently selected from the group consisting of:

6. The compound of claim 1 , wherein L A and L B are each independently selected from the group consisting of:

7. The compound of claim 1 , wherein L A and L B are each independently selected from the group consisting of:

8. The compound of claim 1 , wherein at least one pair of substituents R a , R b , R c , or R d within the same ring are joined and fused into a ring.

9. The compound of claim 1 , wherein L A and L B are connected to form a tetradentate ligand.

10. The compound of claim 1 , wherein L A and L B are connected at two places to form a macrocyclic tetradentate ligand.

11. 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 according to claim 1 .

12. The OLED of claim 11 , wherein the organic layer is an emissive layer and the compound is an emissive dopant or a non-emissive dopant.

13. The OLED of claim 11 , wherein the organic layer further comprises a host,

wherein the host comprises a triphenylene containing benzo-fused thiophene or benzo-fused furan;

wherein any substituent in the host is an unfused substituent independently selected from the group consisting of C n H 2n+1 , OC n H 2n+1 , OAr 1 , N(C n H 2n+1 ) 2 , N(Ar 1 )(Ar 2 ), CH═CH—C n H 2n+1 , C≡CC n H 2n+1 , Ar 1 , Ar 1 -Ar 2 , and C n H 2n -Ar 1 ;

wherein n is from 1 to 10; and wherein Ar 1 and Ar 2 are independently selected from the group consisting of benzene, biphenyl, naphthalene, triphenylene, carbazole, and heteroaromatic analogs thereof.

14. The OLED of claim 11 , wherein the organic layer further comprises a host, wherein the host comprises at least one chemical group selected from the group consisting of triphenylene, carbazole, dibenzothiophene, dibenzofuran, dibenzoselenophene, azatriphenylene, azacarbazole, aza-dibenzothiophene, aza-dibenzofuran, and aza-dibenzoselenophene.

15. The OLED of claim 14 , wherein the host is selected from the group consisting of:

and combinations thereof.

16. The OLED of claim 11 , wherein the organic layer further comprises a host, wherein the host comprises a metal complex.

17. The OLED of claim 11 , wherein L A and L B are connected to form a tetradentate ligand.

18. 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 according to claim 1 .

19. The consumer product of claim 18 , wherein the consumer product is selected from the group consisting of a flat panel display, a curved display, a computer monitor, a medical monitor, a television, a billboard, a light for interior or exterior illumination and/or signaling, a heads-up display, a fully or partially transparent display, a flexible display, a rollable display, a foldable display, a stretchable display, a laser printer, a telephone, a mobile phone, a tablet, a phablet, a personal digital assistant (PDA), a wearable device, a laptop computer, a digital camera, a camcorder, a viewfinder, a micro-display that is less than 2 inches diagonal, a 3-D display, a virtual reality or augmented reality display, a vehicle, a video wall comprising multiple displays tiled together, a theater or stadium screen, and a sign.

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