ELECTROLUMINESCENT MATERIAL AND DEVICE THEREOF

Abstract

Provided are an electroluminescent material and a device thereof. The electroluminescent material is a metal complex having a ligand represented by Formula 1 and can be used as light-emitting materials in electroluminescent devices. These new metal complexes can effectively regulate and control the luminescence wavelength, reduce the drive voltage of electroluminescent devices, greatly improve the current efficiency, power efficiency and EQE of electroluminescent devices, prolong the device lifetime, and provide better device performance. Further provided are an electroluminescent device and a compound composition.

Claims

1. A metal complex, comprising a metal M and a ligand L.sub.a coordinated with the metal M, wherein the metal M is selected from metals having a relative atomic mass greater than 40, and the ligand L.sub.a has a structure represented by Formula 1: ##STR00170## wherein Z.sub.1 and Z.sub.2 are each independently selected from C or N, and Z.sub.1 and Z.sub.2 are different; W is, at each occurrence identically or differently, selected from B, N or P; ring A, ring C, and ring D are, at each occurrence identically or differently, selected from a five-membered unsaturated carbocyclic ring, an aromatic ring having 6 to 30 carbon atoms or a heteroaromatic ring having 3 to 30 carbon atoms; ring B is selected from a hetero ring having 5 to 30 ring atoms; R.sub.a, R.sub.b, R.sub.c, and R.sub.d represent, at each occurrence identically or differently, mono-substitution, multiple substitutions or non-substitution; R.sub.a, R.sub.b, R.sub.c, and R.sub.d are, at each occurrence identically or differently, selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted arylalkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted alkynyl having 2 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a sulfanyl group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof; adjacent substituents R.sub.a, R.sub.b, R.sub.c, and R.sub.d can be optionally joined to form a ring.

2. The metal complex of claim 1, wherein in L.sub.a, ring A, ring C, and ring D are, at each occurrence identically or differently, selected from an aromatic ring having 6 to 18 carbon atoms or a heteroaromatic ring having 3 to 18 carbon atoms; and ring B is selected from a heteroaromatic ring having 5 to 18 ring atoms; preferably, ring A, ring C, and ring D are, at each occurrence identically or differently, selected from an aromatic ring having 6 to 10 carbon atoms or a heteroaromatic ring having 3 to 10 carbon atoms; and ring B is selected from a fused heteroaromatic ring having 8 to 18 ring atoms.

3. The metal complex of claim 1, wherein L.sub.a is selected from a structure represented by any one of Formula 2 to Formula 19: ##STR00171## ##STR00172## ##STR00173## ##STR00174## ##STR00175## ##STR00176## ##STR00177## ##STR00178## ##STR00179## ##STR00180## ##STR00181## ##STR00182## ##STR00183## ##STR00184## ##STR00185## ##STR00186## ##STR00187## and ##STR00188## wherein Z.sub.1 and Z.sub.2 are each independently selected from C or N, and Z.sub.1 and Z.sub.2 are different; W is, at each occurrence identically or differently, selected from B, N or P; A.sub.1 to A.sub.4 are, at each occurrence identically or differently, selected from N or CR.sub.a; B.sub.1 to B.sub.4 are, at each occurrence identically or differently, selected from N or CR.sub.b; C.sub.1 to C.sub.5 are, at each occurrence identically or differently, selected from N or CR.sub.c; D.sub.1 to D.sub.4 are, at each occurrence identically or differently, selected from N or CR.sub.d; Z.sub.3 is, at each occurrence identically or differently, selected from O, S, Se, NR.sub.Z, CR.sub.ZR.sub.Z, SiR.sub.zR.sub.z or PR.sub.z; when two R.sub.z are present at the same time, the two R.sub.z are identical or different; R.sub.a, R.sub.b, R.sub.c, R.sub.d, and R.sub.z are, at each occurrence identically or differently, selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted arylalkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted alkynyl having 2 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a sulfanyl group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof; adjacent substituents R.sub.a, R.sub.b, R.sub.c, R.sub.d, and R.sub.z can be optionally joined to form a ring; preferably, L.sub.a is selected from a structure represented by Formula 2, Formula 4, Formula 7, Formula 10, Formula 16 or Formula 17; more preferably, L.sub.a is selected from a structure represented by Formula 2, Formula 4, Formula 10 or Formula 16.

4. The metal complex of claim 3, wherein in Formula 2 to Formula 19, Z.sub.1 is N, and Z.sub.2 is C.

5. The metal complex of claim 3, wherein in Formula 2 to Formula 19, W is N.

6. The metal complex of claim 3, wherein in Formula 2 to Formula 19, Z.sub.1 is N, and D.sub.1 and/or D.sub.2 are N; or in Formula 2 to Formula 19, Z.sub.2 is N, and C.sub.1 and/or C.sub.2 are N; preferably, in Formula 2 to Formula 19, Z.sub.1 is N, and D.sub.2 is N; or in Formula 2 to Formula 19, Z.sub.2 is N, and C.sub.2 is N.

7. The metal complex of claim 3, wherein in Formula 2 to Formula 19, A.sub.1 to A.sub.4 are each independently selected from CR.sub.a, B.sub.1 to B.sub.4 are each independently selected from CR.sub.b, C.sub.1 to C.sub.5 are each independently selected from CR.sub.c, and D.sub.1 to D.sub.4 are each independently selected from CR.sub.d; R.sub.a, R.sub.b, R.sub.c, and R.sub.d are, at each occurrence identically or differently, selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted arylalkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted alkynyl having 2 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a sulfanyl group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof; adjacent substituents R.sub.a, R.sub.b, R.sub.c, and R.sub.d can be optionally joined to form a ring; preferably, R.sub.a, R.sub.b, R.sub.c, and R.sub.d are, at each occurrence identically or differently, selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, a cyano group, and combinations thereof; more preferably, R.sub.a, R.sub.b, R.sub.c, and R.sub.d are, at each occurrence identically or differently, selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, a cyano group, and combinations thereof.

8. The metal complex of claim 3, wherein in Formula 2 and Formula 4 to Formula 18, at least one of A.sub.1 to A.sub.n is, at each occurrence identically or differently, selected from CR.sub.a, and A.sub.n corresponds to one having the largest serial number among A.sub.1 to A.sub.4 in Formula 2 and Formula 4 to Formula 18; or in Formula 2 to Formula 19, at least one of B.sub.1 to B.sub.n is, at each occurrence identically or differently, selected from CR.sub.b, and B.sub.n corresponds to one having the largest serial number among B.sub.1 to B.sub.4 in any one of Formula 2 to Formula 19; or in Formula 2 to Formula 19, at least one of C.sub.1 to C.sub.n is, at each occurrence identically or differently, selected from CR.sub.c, and C.sub.n corresponds to one having the largest serial number among C.sub.1 to C.sub.5 in any one of Formula 2 to Formula 19; or in Formula 2 to Formula 19, at least one of D.sub.1 to D.sub.n is, at each occurrence identically or differently, selected from CR.sub.d, and D.sub.n corresponds to one having the largest serial number among D.sub.1 to D.sub.4 in any one of Formula 2 to Formula 19; R.sub.a, R.sub.b, R.sub.c, and R.sub.d are, at each occurrence identically or differently, selected from the group consisting of: deuterium, halogen, cyano, hydroxyl, sulfanyl, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted arylalkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, and combinations thereof; adjacent substituents R.sub.a, R.sub.b, R.sub.c, and R.sub.d can be optionally joined to form a ring; preferably, in Formula 2 and Formula 4 to Formula 18, A.sub.1 and/or A.sub.2 are, at each occurrence identically or differently, selected from CR.sub.a; or in Formula 2 to Formula 17, at least one of B.sub.2 to B.sub.4 is, at each occurrence identically or differently, selected from CR.sub.b; in Formula 18 to Formula 19, B.sub.1 and/or B.sub.2 are selected from CR.sub.b; or in Formula 2 to Formula 19, at least one of C.sub.1 to C.sub.3 is, at each occurrence identically or differently, selected from CR.sub.c; or in Formula 2 to Formula 19, D.sub.1 and/or D.sub.2 are selected from CR.sub.d; R.sub.a, R.sub.b, R.sub.c, and R.sub.d are, at each occurrence identically or differently, selected from the group consisting of: deuterium, halogen, cyano, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, and combinations thereof; more preferably, R.sub.a, R.sub.b, R.sub.c, and R.sub.d are, at each occurrence identically or differently, selected from the group consisting of: deuterium, fluorine, cyano, methyl, ethyl, isopropyl, isobutyl, tert-butyl, neopentyl, cyclopentyl, cyclopentylmethyl, cyclohexyl, norbornyl, adamantly, trimethylsilyl, triethylsilyl, trimethylgermanyl, phenyl, pyridyl, triazinyl, trifluoromethyl, methoxy, dimethylamino, deuterated methyl, deuterated ethyl, deuterated isopropyl, deuterated isobutyl, deuterated tert-butyl, deuterated cyclopentyl, deuterated cyclopentylmethyl, deuterated cyclohexyl, deuterated neopentyl, and combinations thereof.

9. The metal complex of claim 1, wherein L.sub.a is, at each occurrence identically or differently, selected from the group consisting of the following: ##STR00189## ##STR00190## ##STR00191## ##STR00192## ##STR00193## ##STR00194## ##STR00195## ##STR00196## ##STR00197## ##STR00198## ##STR00199## ##STR00200## ##STR00201## ##STR00202## ##STR00203## ##STR00204## ##STR00205## ##STR00206## ##STR00207## ##STR00208## ##STR00209## ##STR00210## ##STR00211## ##STR00212## ##STR00213## ##STR00214## ##STR00215## ##STR00216## ##STR00217## ##STR00218## ##STR00219## ##STR00220## ##STR00221## ##STR00222## ##STR00223## ##STR00224## ##STR00225## ##STR00226## ##STR00227## ##STR00228## ##STR00229## ##STR00230## ##STR00231## ##STR00232## ##STR00233## ##STR00234## ##STR00235## ##STR00236## ##STR00237## ##STR00238## ##STR00239## ##STR00240## ##STR00241## ##STR00242## ##STR00243## ##STR00244## ##STR00245## ##STR00246## ##STR00247## ##STR00248## ##STR00249## ##STR00250## ##STR00251## ##STR00252## ##STR00253## ##STR00254## ##STR00255## ##STR00256## ##STR00257## ##STR00258## ##STR00259## ##STR00260## ##STR00261## ##STR00262## ##STR00263## ##STR00264## ##STR00265## ##STR00266## ##STR00267## ##STR00268## ##STR00269## ##STR00270## ##STR00271## ##STR00272## ##STR00273## ##STR00274## ##STR00275## ##STR00276## ##STR00277## ##STR00278## ##STR00279## ##STR00280## ##STR00281## ##STR00282## ##STR00283## ##STR00284## ##STR00285## ##STR00286## ##STR00287## ##STR00288## ##STR00289## ##STR00290## ##STR00291## ##STR00292## ##STR00293## ##STR00294## ##STR00295## ##STR00296## ##STR00297## ##STR00298## ##STR00299## ##STR00300## ##STR00301## ##STR00302## ##STR00303## ##STR00304## ##STR00305## ##STR00306## ##STR00307## ##STR00308## ##STR00309## ##STR00310## ##STR00311## ##STR00312## ##STR00313## ##STR00314## ##STR00315## ##STR00316## ##STR00317## ##STR00318## ##STR00319## ##STR00320## ##STR00321## ##STR00322## ##STR00323## ##STR00324## ##STR00325## ##STR00326## ##STR00327## ##STR00328## ##STR00329## ##STR00330## ##STR00331## ##STR00332## ##STR00333## ##STR00334## ##STR00335## ##STR00336## ##STR00337## ##STR00338## ##STR00339## ##STR00340## ##STR00341## ##STR00342## ##STR00343## ##STR00344## ##STR00345## ##STR00346## ##STR00347## ##STR00348## ##STR00349## ##STR00350## ##STR00351## ##STR00352## ##STR00353## ##STR00354## ##STR00355## ##STR00356## ##STR00357## ##STR00358## ##STR00359## ##STR00360## ##STR00361## ##STR00362## ##STR00363## ##STR00364## ##STR00365## ##STR00366## ##STR00367## ##STR00368## ##STR00369## ##STR00370## ##STR00371## ##STR00372## ##STR00373## ##STR00374## ##STR00375## ##STR00376## ##STR00377## ##STR00378## ##STR00379## ##STR00380## ##STR00381## ##STR00382## ##STR00383## ##STR00384## ##STR00385## ##STR00386## ##STR00387## ##STR00388## ##STR00389## ##STR00390## ##STR00391## ##STR00392## ##STR00393## ##STR00394## ##STR00395## ##STR00396## ##STR00397## ##STR00398## ##STR00399## ##STR00400## ##STR00401## ##STR00402## ##STR00403## ##STR00404## ##STR00405## ##STR00406## ##STR00407## ##STR00408## ##STR00409## ##STR00410## ##STR00411## ##STR00412## ##STR00413## ##STR00414## ##STR00415## ##STR00416## ##STR00417## ##STR00418## ##STR00419## ##STR00420## ##STR00421## ##STR00422## ##STR00423## ##STR00424## ##STR00425## ##STR00426## ##STR00427## ##STR00428## ##STR00429## ##STR00430## ##STR00431## ##STR00432## ##STR00433## ##STR00434## ##STR00435## ##STR00436## ##STR00437## ##STR00438## ##STR00439## ##STR00440## ##STR00441## ##STR00442## ##STR00443## ##STR00444## ##STR00445## ##STR00446## ##STR00447## ##STR00448## ##STR00449## ##STR00450## ##STR00451## ##STR00452## ##STR00453## ##STR00454## ##STR00455## ##STR00456## ##STR00457## ##STR00458## ##STR00459## ##STR00460## ##STR00461## ##STR00462## ##STR00463## ##STR00464## ##STR00465## ##STR00466## ##STR00467## ##STR00468## ##STR00469## ##STR00470## ##STR00471## ##STR00472## ##STR00473## ##STR00474## ##STR00475## ##STR00476## ##STR00477## ##STR00478## ##STR00479## ##STR00480## ##STR00481## ##STR00482## ##STR00483## ##STR00484## ##STR00485## ##STR00486## ##STR00487## ##STR00488## ##STR00489## ##STR00490## ##STR00491## ##STR00492## ##STR00493## ##STR00494## ##STR00495## ##STR00496## ##STR00497## ##STR00498## ##STR00499## ##STR00500## ##STR00501## ##STR00502## ##STR00503## ##STR00504## ##STR00505## ##STR00506## ##STR00507## ##STR00508## ##STR00509## ##STR00510## ##STR00511## ##STR00512## ##STR00513## ##STR00514## ##STR00515## ##STR00516## ##STR00517## ##STR00518## ##STR00519## ##STR00520## ##STR00521## ##STR00522## ##STR00523## ##STR00524## ##STR00525## ##STR00526## ##STR00527## ##STR00528## ##STR00529## ##STR00530## ##STR00531## ##STR00532## ##STR00533## ##STR00534## ##STR00535## ##STR00536## ##STR00537## ##STR00538## ##STR00539## ##STR00540## ##STR00541## ##STR00542## ##STR00543## ##STR00544## ##STR00545## ##STR00546## ##STR00547## ##STR00548## ##STR00549## ##STR00550## ##STR00551## ##STR00552## ##STR00553## ##STR00554## ##STR00555## ##STR00556## ##STR00557## ##STR00558## ##STR00559## ##STR00560## ##STR00561## ##STR00562## ##STR00563## ##STR00564## ##STR00565## ##STR00566## ##STR00567## ##STR00568## ##STR00569## ##STR00570## ##STR00571## ##STR00572## ##STR00573## ##STR00574## ##STR00575## ##STR00576## ##STR00577## ##STR00578## ##STR00579## ##STR00580## ##STR00581## ##STR00582## ##STR00583## ##STR00584## ##STR00585## ##STR00586## ##STR00587## ##STR00588## ##STR00589## ##STR00590## ##STR00591## ##STR00592## ##STR00593## ##STR00594## ##STR00595## ##STR00596## ##STR00597## ##STR00598## ##STR00599## ##STR00600## ##STR00601## ##STR00602## ##STR00603## ##STR00604## ##STR00605## ##STR00606## ##STR00607## ##STR00608## ##STR00609## ##STR00610## ##STR00611## ##STR00612## ##STR00613## ##STR00614## ##STR00615## ##STR00616## ##STR00617## ##STR00618## ##STR00619## ##STR00620## ##STR00621## ##STR00622## ##STR00623## ##STR00624## ##STR00625## ##STR00626## ##STR00627## ##STR00628## ##STR00629## ##STR00630## ##STR00631## ##STR00632## ##STR00633## ##STR00634## ##STR00635## ##STR00636## ##STR00637## ##STR00638## ##STR00639## ##STR00640## ##STR00641## ##STR00642## ##STR00643## ##STR00644## ##STR00645## ##STR00646## ##STR00647## ##STR00648## ##STR00649## ##STR00650## ##STR00651## ##STR00652## ##STR00653## ##STR00654## ##STR00655## ##STR00656## ##STR00657## ##STR00658## ##STR00659## ##STR00660## ##STR00661## ##STR00662## ##STR00663## ##STR00664## ##STR00665## ##STR00666## ##STR00667## ##STR00668## ##STR00669## ##STR00670## ##STR00671## ##STR00672## ##STR00673## ##STR00674## ##STR00675## ##STR00676## ##STR00677## ##STR00678## ##STR00679## ##STR00680## ##STR00681## ##STR00682## ##STR00683## ##STR00684## ##STR00685## ##STR00686## ##STR00687## ##STR00688## ##STR00689## ##STR00690## ##STR00691## ##STR00692## ##STR00693## ##STR00694## ##STR00695## ##STR00696## ##STR00697## ##STR00698## ##STR00699## ##STR00700## ##STR00701## ##STR00702## ##STR00703## ##STR00704## ##STR00705## ##STR00706## ##STR00707## ##STR00708## ##STR00709## ##STR00710## ##STR00711## ##STR00712## ##STR00713## ##STR00714## ##STR00715## ##STR00716## ##STR00717## ##STR00718## ##STR00719## ##STR00720## ##STR00721## ##STR00722## ##STR00723## ##STR00724## ##STR00725## ##STR00726## ##STR00727## ##STR00728## ##STR00729## ##STR00730## ##STR00731## ##STR00732## ##STR00733## ##STR00734## ##STR00735## ##STR00736## ##STR00737## ##STR00738## ##STR00739## ##STR00740## ##STR00741## ##STR00742## ##STR00743## ##STR00744## ##STR00745## ##STR00746## ##STR00747## ##STR00748## ##STR00749## ##STR00750## ##STR00751## ##STR00752## ##STR00753## ##STR00754## ##STR00755## ##STR00756## ##STR00757## ##STR00758## ##STR00759## ##STR00760## ##STR00761## ##STR00762## ##STR00763## ##STR00764## ##STR00765## ##STR00766## ##STR00767## ##STR00768## ##STR00769## ##STR00770## ##STR00771## ##STR00772## ##STR00773## ##STR00774## ##STR00775## ##STR00776## ##STR00777## ##STR00778## ##STR00779## ##STR00780## ##STR00781## ##STR00782## ##STR00783## ##STR00784## ##STR00785## ##STR00786## ##STR00787## ##STR00788## ##STR00789## ##STR00790## ##STR00791## ##STR00792## ##STR00793## ##STR00794## ##STR00795## ##STR00796## ##STR00797## ##STR00798## ##STR00799## ##STR00800## ##STR00801## ##STR00802## ##STR00803## ##STR00804## ##STR00805## ##STR00806## ##STR00807## ##STR00808## ##STR00809## ##STR00810## ##STR00811## ##STR00812## ##STR00813## ##STR00814## ##STR00815## ##STR00816## ##STR00817## ##STR00818## ##STR00819## ##STR00820## ##STR00821## ##STR00822## ##STR00823## ##STR00824## ##STR00825## ##STR00826## ##STR00827## ##STR00828## ##STR00829## ##STR00830## ##STR00831## ##STR00832## ##STR00833## ##STR00834## ##STR00835## ##STR00836## ##STR00837## ##STR00838## ##STR00839## ##STR00840## ##STR00841## ##STR00842## ##STR00843## ##STR00844## ##STR00845## ##STR00846## ##STR00847## ##STR00848## ##STR00849## ##STR00850## ##STR00851## ##STR00852## ##STR00853## ##STR00854## ##STR00855## ##STR00856## ##STR00857## ##STR00858## ##STR00859## ##STR00860## ##STR00861## ##STR00862## ##STR00863## ##STR00864## ##STR00865## ##STR00866## ##STR00867## ##STR00868## ##STR00869## ##STR00870## ##STR00871## ##STR00872## ##STR00873## ##STR00874## ##STR00875## ##STR00876## ##STR00877## ##STR00878## ##STR00879## ##STR00880## ##STR00881## ##STR00882## ##STR00883## ##STR00884## ##STR00885## ##STR00886## ##STR00887## ##STR00888## ##STR00889## ##STR00890## ##STR00891## ##STR00892## ##STR00893## ##STR00894## ##STR00895## ##STR00896## ##STR00897## ##STR00898## ##STR00899## ##STR00900## ##STR00901## ##STR00902## ##STR00903## ##STR00904## ##STR00905## ##STR00906## ##STR00907## ##STR00908## ##STR00909## ##STR00910## ##STR00911## ##STR00912## ##STR00913## ##STR00914## ##STR00915## ##STR00916## ##STR00917## ##STR00918## ##STR00919## ##STR00920## ##STR00921## ##STR00922## ##STR00923## ##STR00924## ##STR00925## ##STR00926## ##STR00927## ##STR00928## ##STR00929## ##STR00930## ##STR00931## ##STR00932## ##STR00933## ##STR00934## ##STR00935## ##STR00936## ##STR00937## ##STR00938## ##STR00939## ##STR00940## ##STR00941## ##STR00942## ##STR00943## ##STR00944## ##STR00945## ##STR00946## ##STR00947## ##STR00948## ##STR00949## ##STR00950## ##STR00951## ##STR00952## ##STR00953## ##STR00954## ##STR00955## ##STR00956## ##STR00957## ##STR00958## ##STR00959## ##STR00960## ##STR00961## ##STR00962## ##STR00963## ##STR00964## ##STR00965## ##STR00966## ##STR00967## ##STR00968## ##STR00969## ##STR00970## ##STR00971## ##STR00972## ##STR00973## ##STR00974## ##STR00975## ##STR00976## ##STR00977## ##STR00978## ##STR00979## ##STR00980## ##STR00981## ##STR00982## ##STR00983## ##STR00984## ##STR00985## ##STR00986## ##STR00987## ##STR00988## ##STR00989## ##STR00990## ##STR00991## ##STR00992## ##STR00993## ##STR00994## ##STR00995## ##STR00996## ##STR00997## ##STR00998## ##STR00999## ##STR01000## ##STR01001## ##STR01002## ##STR01003## ##STR01004## ##STR01005## ##STR01006## ##STR01007## ##STR01008## ##STR01009## ##STR01010## ##STR01011## ##STR01012## ##STR01013## ##STR01014## ##STR01015## ##STR01016## ##STR01017## ##STR01018## ##STR01019## ##STR01020## ##STR01021## ##STR01022## ##STR01023## ##STR01024## ##STR01025## ##STR01026## ##STR01027## ##STR01028## ##STR01029## ##STR01030## ##STR01031## ##STR01032## ##STR01033## ##STR01034## ##STR01035## ##STR01036## ##STR01037## ##STR01038## ##STR01039## ##STR01040## ##STR01041## ##STR01042## ##STR01043## ##STR01044## ##STR01045## ##STR01046## ##STR01047## ##STR01048## ##STR01049## ##STR01050## ##STR01051## ##STR01052## ##STR01053## ##STR01054## ##STR01055## ##STR01056## ##STR01057## ##STR01058## ##STR01059## ##STR01060## ##STR01061## ##STR01062## ##STR01063## ##STR01064## ##STR01065## ##STR01066## ##STR01067## ##STR01068## ##STR01069## ##STR01070## ##STR01071## ##STR01072## ##STR01073## ##STR01074## ##STR01075## ##STR01076## ##STR01077## ##STR01078## ##STR01079## ##STR01080## ##STR01081## ##STR01082## ##STR01083## ##STR01084## ##STR01085## ##STR01086## ##STR01087## ##STR01088## ##STR01089## ##STR01090## ##STR01091## ##STR01092## ##STR01093## ##STR01094## ##STR01095## ##STR01096## ##STR01097## ##STR01098## ##STR01099## ##STR01100## ##STR01101## ##STR01102## ##STR01103## ##STR01104## ##STR01105## ##STR01106## ##STR01107## ##STR01108## ##STR01109## ##STR01110## ##STR01111## ##STR01112## ##STR01113## ##STR01114## ##STR01115## ##STR01116## ##STR01117## ##STR01118## ##STR01119## ##STR01120## ##STR01121## ##STR01122## ##STR01123## ##STR01124## ##STR01125## ##STR01126## ##STR01127## ##STR01128## ##STR01129## ##STR01130## ##STR01131## ##STR01132## ##STR01133## ##STR01134## ##STR01135## ##STR01136## ##STR01137## ##STR01138## ##STR01139## ##STR01140## ##STR01141## ##STR01142## ##STR01143## ##STR01144## ##STR01145## ##STR01146## ##STR01147## ##STR01148## ##STR01149## ##STR01150## ##STR01151## ##STR01152## ##STR01153## ##STR01154## ##STR01155## ##STR01156## ##STR01157## ##STR01158## ##STR01159## ##STR01160## ##STR01161## ##STR01162## ##STR01163## ##STR01164## ##STR01165## ##STR01166## ##STR01167## ##STR01168## ##STR01169## ##STR01170## ##STR01171## ##STR01172## ##STR01173## ##STR01174## ##STR01175## ##STR01176## ##STR01177## ##STR01178## ##STR01179## ##STR01180## ##STR01181## ##STR01182## ##STR01183## ##STR01184## ##STR01185## ##STR01186## ##STR01187## ##STR01188## ##STR01189## ##STR01190## ##STR01191## ##STR01192## ##STR01193## ##STR01194## ##STR01195## ##STR01196## ##STR01197## ##STR01198## ##STR01199## ##STR01200## ##STR01201## ##STR01202## ##STR01203## ##STR01204## ##STR01205## ##STR01206## ##STR01207## ##STR01208## ##STR01209## ##STR01210## ##STR01211## ##STR01212## ##STR01213## ##STR01214## ##STR01215## ##STR01216## ##STR01217## ##STR01218## ##STR01219## ##STR01220## ##STR01221## ##STR01222## ##STR01223## ##STR01224## ##STR01225## ##STR01226## ##STR01227## ##STR01228## ##STR01229## ##STR01230## ##STR01231## ##STR01232## ##STR01233## ##STR01234## ##STR01235## ##STR01236## ##STR01237## ##STR01238## ##STR01239## ##STR01240## ##STR01241## ##STR01242## ##STR01243## ##STR01244## ##STR01245## ##STR01246## ##STR01247## ##STR01248## ##STR01249## ##STR01250## ##STR01251## ##STR01252## ##STR01253## ##STR01254## ##STR01255## ##STR01256## ##STR01257## ##STR01258## ##STR01259## ##STR01260## ##STR01261## ##STR01262## ##STR01263## ##STR01264## ##STR01265## ##STR01266## ##STR01267## ##STR01268## ##STR01269## ##STR01270## ##STR01271## ##STR01272## ##STR01273## ##STR01274## ##STR01275## ##STR01276## ##STR01277## ##STR01278## ##STR01279## ##STR01280## ##STR01281## ##STR01282## ##STR01283## ##STR01284## ##STR01285## ##STR01286## ##STR01287## ##STR01288## ##STR01289## ##STR01290## ##STR01291## ##STR01292## ##STR01293## ##STR01294## ##STR01295## ##STR01296## ##STR01297## ##STR01298## ##STR01299## ##STR01300## ##STR01301## ##STR01302## ##STR01303## ##STR01304## ##STR01305## ##STR01306## ##STR01307## ##STR01308## ##STR01309## ##STR01310## ##STR01311## ##STR01312## ##STR01313## ##STR01314## ##STR01315## ##STR01316## ##STR01317## ##STR01318## ##STR01319## ##STR01320## ##STR01321## ##STR01322## ##STR01323## ##STR01324## ##STR01325## ##STR01326## ##STR01327## ##STR01328## ##STR01329## ##STR01330## ##STR01331## ##STR01332## ##STR01333## ##STR01334## ##STR01335## ##STR01336## ##STR01337## ##STR01338## ##STR01339## ##STR01340## ##STR01341## ##STR01342## ##STR01343## ##STR01344## ##STR01345## ##STR01346## ##STR01347## ##STR01348## ##STR01349## ##STR01350## ##STR01351## ##STR01352## ##STR01353## ##STR01354## ##STR01355## ##STR01356## ##STR01357## ##STR01358## ##STR01359## ##STR01360## ##STR01361## ##STR01362## ##STR01363## ##STR01364## ##STR01365## ##STR01366## ##STR01367## ##STR01368## ##STR01369## ##STR01370## ##STR01371## ##STR01372## ##STR01373## ##STR01374## ##STR01375## ##STR01376## ##STR01377## ##STR01378## ##STR01379## ##STR01380## ##STR01381## ##STR01382## ##STR01383## ##STR01384## ##STR01385## ##STR01386## ##STR01387## ##STR01388## ##STR01389## ##STR01390## ##STR01391## ##STR01392## ##STR01393## ##STR01394## ##STR01395## ##STR01396## ##STR01397## ##STR01398## ##STR01399## ##STR01400## ##STR01401## ##STR01402## ##STR01403## ##STR01404## ##STR01405## ##STR01406## ##STR01407## ##STR01408## ##STR01409## ##STR01410## ##STR01411## ##STR01412## ##STR01413## ##STR01414## ##STR01415## ##STR01416## ##STR01417## ##STR01418## ##STR01419## ##STR01420## ##STR01421## ##STR01422## ##STR01423## ##STR01424## ##STR01425## ##STR01426## ##STR01427## ##STR01428## ##STR01429## wherein TMS represents trimethylsilyl, and Ph represents phenyl; optionally, hydrogens in the structures L.sub.a1 to L.sub.a1241 can be partially or completely substituted with deuterium.

10. The metal complex of claim 1, wherein the metal complex has a general formula of M(L.sub.a).sub.m(L.sub.b).sub.n(L.sub.c).sub.q; wherein the metal M is selected from Ir, Rh, Re, Os, Pt, Au or Cu; L.sub.a, L.sub.b, and L.sub.c are a first ligand, a second ligand and a third ligand coordinated to the metal M, respectively; m is selected from 1, 2 or 3, n is selected from 0, 1 or 2, q is selected from 0, 1 or 2, and m+n+q is equal to an oxidation state of the metal M; when m is equal to 2 or 3, a plurality of L.sub.a can be identical or different; when n is equal to 2, two L.sub.b can be identical or different; and when q is equal to 2, two L.sub.c can be identical or different; L.sub.a, L.sub.b, and L.sub.c can be optionally joined to form a multidentate ligand; L.sub.b and L.sub.c are, at each occurrence identically or differently, selected from the group consisting of the following structures: ##STR01430## ##STR01431## ##STR01432## ##STR01433## ##STR01434## ##STR01435## ##STR01436## ##STR01437## ##STR01438## ##STR01439## ##STR01440## ##STR01441## wherein R.sub.i, R.sub.ii, and R.sub.iii represent, at each occurrence identically or differently, mono-substitution, multiple substitutions or non-substitution; X.sub.a is, at each occurrence identically or differently, selected from the group consisting of: O, S, Se, NR.sub.N1, and CR.sub.C1R.sub.C2; X.sub.b and X.sub.c are, at each occurrence identically or differently, selected from the group consisting of: O, S, Se and NR.sub.N2; R.sub.i, R.sub.ii, R.sub.iii, R.sub.N1, R.sub.N2, R.sub.c1, and R.sub.C2 are, at each occurrence identically or differently, selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted arylalkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted alkynyl having 2 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a sulfanyl group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof; adjacent substituents R.sub.i, R.sub.ii, R.sub.iii, R.sub.N1, R.sub.N2, R.sub.C1 and R.sub.C2 can be optionally joined to form a ring; preferably, the metal M is selected from Ir, Pt or Os; more preferably, the metal M is Ir.

11. The metal complex of claim 10, wherein L.sub.b is, at each occurrence identically or differently, selected from the following structure: ##STR01442## wherein R.sub.1 to R.sub.7 are, at each occurrence identically or differently, selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted arylalkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted alkynyl having 2 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to Y, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 toY, substituted or unsubstituted alkylgermanyl having 3 to Y, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to Y, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a sulfanyl group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof; preferably, at least one or two of R.sub.1 to R.sub.3 is(are), at each occurrence identically or differently, selected from substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms or combinations thereof; and/or at least one or two of R.sub.4 to R.sub.6 is(are), at each occurrence identically or differently, selected from substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms or combinations thereof; more preferably, at least two of R.sub.1 to R.sub.3 are, at each occurrence identically or differently, selected from substituted or unsubstituted alkyl having 2 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 2 to 20 carbon atoms or combinations thereof; and/or at least two of R.sub.4 to R.sub.6 are, at each occurrence identically or differently, selected from substituted or unsubstituted alkyl having 2 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 2 to 20 carbon atoms or combinations thereof.

12. The metal complex of claim 10, wherein L.sub.c is, at each occurrence identically or differently, selected from the following structure: ##STR01443## wherein R.sub.8 to R.sub.15 are, at each occurrence identically or differently, selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted arylalkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a sulfanyl group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof; adjacent substituents R.sub.8 to R.sub.15 can be optionally joined to form a ring.

13. The metal complex of claim 10, wherein L.sub.b is, at each occurrence identically or differently, selected from the group consisting of the following structures: ##STR01444## ##STR01445## ##STR01446## ##STR01447## ##STR01448## ##STR01449## ##STR01450## ##STR01451## ##STR01452## ##STR01453## ##STR01454## ##STR01455## ##STR01456## ##STR01457## ##STR01458## ##STR01459## ##STR01460## ##STR01461## ##STR01462## ##STR01463## ##STR01464## ##STR01465## ##STR01466## ##STR01467## ##STR01468## ##STR01469## ##STR01470## ##STR01471## ##STR01472## ##STR01473## ##STR01474## ##STR01475## ##STR01476## ##STR01477## ##STR01478## ##STR01479## ##STR01480## ##STR01481## ##STR01482## ##STR01483## ##STR01484## ##STR01485## ##STR01486## ##STR01487## ##STR01488## ##STR01489## ##STR01490## ##STR01491## ##STR01492## ##STR01493## ##STR01494## ##STR01495## ##STR01496## ##STR01497## ##STR01498## ##STR01499## ##STR01500## ##STR01501## ##STR01502## ##STR01503## ##STR01504## ##STR01505## ##STR01506## ##STR01507## ##STR01508## ##STR01509## ##STR01510## ##STR01511## ##STR01512## ##STR01513## ##STR01514## ##STR01515## ##STR01516## ##STR01517## ##STR01518## ##STR01519## ##STR01520## ##STR01521## ##STR01522## ##STR01523## ##STR01524## ##STR01525## ##STR01526## ##STR01527## ##STR01528## ##STR01529## ##STR01530## ##STR01531## ##STR01532## ##STR01533## ##STR01534## ##STR01535## ##STR01536## ##STR01537## ##STR01538## ##STR01539## ##STR01540## ##STR01541## ##STR01542## ##STR01543## ##STR01544## ##STR01545## ##STR01546## ##STR01547## ##STR01548## ##STR01549## ##STR01550## ##STR01551## ##STR01552## ##STR01553## ##STR01554## ##STR01555## ##STR01556## ##STR01557## ##STR01558## ##STR01559## ##STR01560## ##STR01561## ##STR01562## ##STR01563## ##STR01564## ##STR01565## ##STR01566## ##STR01567## ##STR01568## ##STR01569## ##STR01570## ##STR01571## ##STR01572## ##STR01573## ##STR01574## ##STR01575## ##STR01576## ##STR01577## ##STR01578## ##STR01579## ##STR01580## ##STR01581## ##STR01582## ##STR01583## ##STR01584## ##STR01585## ##STR01586## ##STR01587## ##STR01588## ##STR01589## ##STR01590## ##STR01591## ##STR01592## ##STR01593## ##STR01594## ##STR01595## ##STR01596## ##STR01597## ##STR01598## ##STR01599## ##STR01600## ##STR01601## ##STR01602## ##STR01603## ##STR01604## ##STR01605## ##STR01606## ##STR01607## ##STR01608## ##STR01609## ##STR01610## ##STR01611## ##STR01612## ##STR01613## ##STR01614## ##STR01615## ##STR01616## ##STR01617## ##STR01618## ##STR01619## ##STR01620## ##STR01621## ##STR01622## ##STR01623## ##STR01624## ##STR01625## ##STR01626## ##STR01627## ##STR01628## ##STR01629## ##STR01630## ##STR01631## ##STR01632## ##STR01633## ##STR01634## ##STR01635## ##STR01636## ##STR01637## ##STR01638## ##STR01639## ##STR01640## ##STR01641## ##STR01642## ##STR01643## ##STR01644## ##STR01645## ##STR01646## ##STR01647## ##STR01648## ##STR01649## ##STR01650## ##STR01651## ##STR01652## ##STR01653## ##STR01654## ##STR01655## ##STR01656## ##STR01657## ##STR01658## ##STR01659## ##STR01660## ##STR01661## ##STR01662## ##STR01663## ##STR01664## ##STR01665## ##STR01666## ##STR01667## ##STR01668## ##STR01669## ##STR01670## ##STR01671## ##STR01672## ##STR01673## ##STR01674## ##STR01675## ##STR01676## ##STR01677## ##STR01678## ##STR01679## ##STR01680## ##STR01681## ##STR01682## ##STR01683## ##STR01684## ##STR01685## ##STR01686## ##STR01687## ##STR01688## ##STR01689## ##STR01690## ##STR01691## ##STR01692## ##STR01693## ##STR01694## ##STR01695## ##STR01696## ##STR01697## ##STR01698## ##STR01699## ##STR01700## ##STR01701## ##STR01702## ##STR01703## ##STR01704## ##STR01705## ##STR01706## ##STR01707## ##STR01708## ##STR01709## ##STR01710## ##STR01711## ##STR01712## ##STR01713## ##STR01714## ##STR01715## ##STR01716## ##STR01717## ##STR01718## ##STR01719## ##STR01720## ##STR01721## ##STR01722## ##STR01723## ##STR01724## ##STR01725## ##STR01726## ##STR01727## ##STR01728## ##STR01729## ##STR01730## ##STR01731## ##STR01732## ##STR01733## ##STR01734## ##STR01735## ##STR01736## ##STR01737## ##STR01738## ##STR01739## ##STR01740## ##STR01741## ##STR01742## ##STR01743## ##STR01744## ##STR01745## ##STR01746## ##STR01747## ##STR01748## ##STR01749## ##STR01750## ##STR01751## ##STR01752## ##STR01753## ##STR01754## ##STR01755## ##STR01756## ##STR01757## ##STR01758## ##STR01759## ##STR01760## ##STR01761## ##STR01762## ##STR01763## ##STR01764## ##STR01765## wherein L.sub.c is, at each occurrence identically or differently, selected from the group consisting of the following structures: ##STR01766## ##STR01767## ##STR01768## ##STR01769## ##STR01770## ##STR01771## ##STR01772## ##STR01773## ##STR01774## ##STR01775## ##STR01776## ##STR01777## ##STR01778## ##STR01779## ##STR01780## ##STR01781## ##STR01782## ##STR01783## ##STR01784## ##STR01785## ##STR01786## ##STR01787## ##STR01788## ##STR01789## ##STR01790## ##STR01791## ##STR01792## ##STR01793## ##STR01794## ##STR01795## ##STR01796## ##STR01797## ##STR01798## ##STR01799## ##STR01800## ##STR01801## ##STR01802## ##STR01803## ##STR01804## ##STR01805## ##STR01806## ##STR01807## ##STR01808## ##STR01809## ##STR01810## ##STR01811## ##STR01812## ##STR01813## ##STR01814## ##STR01815## ##STR01816## ##STR01817## ##STR01818## ##STR01819## ##STR01820## ##STR01821## ##STR01822## ##STR01823## ##STR01824## ##STR01825## ##STR01826## ##STR01827## ##STR01828## ##STR01829## ##STR01830## ##STR01831## ##STR01832## ##STR01833## ##STR01834## ##STR01835## ##STR01836## ##STR01837## ##STR01838## ##STR01839## ##STR01840## ##STR01841## ##STR01842## ##STR01843## ##STR01844## ##STR01845## ##STR01846## ##STR01847## ##STR01848## ##STR01849## ##STR01850## ##STR01851## ##STR01852## ##STR01853## ##STR01854## ##STR01855## ##STR01856## ##STR01857## ##STR01858## ##STR01859## ##STR01860## ##STR01861## ##STR01862## ##STR01863## ##STR01864## ##STR01865## ##STR01866## ##STR01867## ##STR01868## ##STR01869## ##STR01870## ##STR01871## ##STR01872## ##STR01873## ##STR01874## ##STR01875## ##STR01876## ##STR01877## ##STR01878## ##STR01879## ##STR01880## ##STR01881## ##STR01882## ##STR01883## ##STR01884## ##STR01885## ##STR01886## ##STR01887## ##STR01888## ##STR01889## ##STR01890## ##STR01891## ##STR01892## ##STR01893## ##STR01894## ##STR01895## ##STR01896## ##STR01897## ##STR01898## ##STR01899## ##STR01900## ##STR01901## ##STR01902## ##STR01903## ##STR01904## ##STR01905## ##STR01906## ##STR01907## ##STR01908## ##STR01909## ##STR01910## ##STR01911## ##STR01912## ##STR01913## ##STR01914## ##STR01915## ##STR01916## ##STR01917## ##STR01918## ##STR01919## ##STR01920## ##STR01921## ##STR01922## ##STR01923## ##STR01924## ##STR01925## ##STR01926## ##STR01927## ##STR01928## ##STR01929## ##STR01930## ##STR01931## ##STR01932## ##STR01933## ##STR01934## ##STR01935## ##STR01936## ##STR01937## ##STR01938## ##STR01939## ##STR01940## ##STR01941## ##STR01942## ##STR01943## ##STR01944## ##STR01945## ##STR01946## ##STR01947## ##STR01948## ##STR01949## ##STR01950## ##STR01951## ##STR01952## ##STR01953## ##STR01954## ##STR01955## ##STR01956## ##STR01957## ##STR01958## ##STR01959## ##STR01960## ##STR01961## ##STR01962## ##STR01963## ##STR01964## ##STR01965## ##STR01966## ##STR01967## ##STR01968## ##STR01969## ##STR01970## ##STR01971## ##STR01972## ##STR01973## ##STR01974## ##STR01975## ##STR01976## ##STR01977## ##STR01978## ##STR01979## ##STR01980## ##STR01981## ##STR01982## ##STR01983## ##STR01984## ##STR01985## ##STR01986## ##STR01987## ##STR01988## ##STR01989## ##STR01990## ##STR01991## ##STR01992## ##STR01993## ##STR01994## ##STR01995## ##STR01996## ##STR01997## ##STR01998## ##STR01999## ##STR02000## ##STR02001## ##STR02002## ##STR02003## ##STR02004## ##STR02005## ##STR02006## ##STR02007## ##STR02008## ##STR02009## ##STR02010## ##STR02011## ##STR02012## ##STR02013## ##STR02014## ##STR02015## ##STR02016## ##STR02017## ##STR02018## ##STR02019## ##STR02020## ##STR02021## ##STR02022## ##STR02023## ##STR02024## ##STR02025## ##STR02026## ##STR02027## ##STR02028## ##STR02029## ##STR02030## ##STR02031## ##STR02032## ##STR02033## ##STR02034## ##STR02035## ##STR02036## ##STR02037## ##STR02038## ##STR02039## ##STR02040## ##STR02041## ##STR02042## ##STR02043## ##STR02044## ##STR02045## ##STR02046## ##STR02047## ##STR02048## ##STR02049## ##STR02050## ##STR02051## ##STR02052## ##STR02053## ##STR02054## ##STR02055## ##STR02056## ##STR02057## ##STR02058## ##STR02059## ##STR02060## ##STR02061## ##STR02062## ##STR02063## ##STR02064## ##STR02065## ##STR02066## ##STR02067## ##STR02068## ##STR02069## ##STR02070## ##STR02071## ##STR02072## ##STR02073## ##STR02074## ##STR02075## ##STR02076## ##STR02077## ##STR02078## ##STR02079## ##STR02080## ##STR02081## ##STR02082## ##STR02083## .

14. The metal complex of claim 13, wherein the metal complex is an Ir complex and has a structure represented by any one of Ir(L.sub.a)(L.sub.b)(L.sub.c), Ir(L.sub.a).sub.2(L.sub.b), Ir(L.sub.a).sub.2(L.sub.c), and Ir(L.sub.a)(L.sub.c).sub.2; when the metal complex has a structure of Ir(L.sub.a)(L.sub.b)(L.sub.c), L.sub.a is selected from any one of the group consisting of L.sub.a1 to L.sub.a1241, L.sub.b is selected from any one of the group consisting of L.sub.b1 to L.sub.b322, and L.sub.c is selected from any one of the group consisting of L.sub.c1 to L.sub.c321; when the metal complex has a structure of Ir(L.sub.a).sub.2(L.sub.b), L.sub.a is, at each occurrence identically or differently, selected from any one or any two of the group consisting of L.sub.a1 to L.sub.a1241, and L.sub.b is selected from any one of the group consisting of L.sub.b1 to L.sub.b322; when the metal complex has a structure of Ir(L.sub.a).sub.2(L.sub.c), L.sub.a is, at each occurrence identically or differently, selected from any one or any two of the group consisting of L.sub.a1 to L.sub.a1241, and L.sub.c is selected from any one of the group consisting of L.sub.c1 to L.sub.c321; when the metal complex has a structure of Ir(L.sub.a)(L.sub.c).sub.2, L.sub.a is selected from any one of the group consisting of L.sub.a1 to L.sub.a1241, and L.sub.c is, at each occurrence identically or differently, selected from any one or any two of the group consisting of L.sub.c1 to L.sub.c321; optionally, hydrogens in the structure of the metal complex can be partially or completely substituted with deuterium; preferably, the metal complex is selected from the group consisting of Compound 1 to Compound 670; wherein Compound 1 to Compound 538, Compound 669, and Compound 670 have the general formula of Ir(L.sub.a).sub.2(L.sub.b), wherein two L.sub.a are identical, and L.sub.a and L.sub.b are selected from structures listed in the following table, respectively: TABLE-US-00007 Compound No. L.sub.a L.sub.b Compound No. L.sub.a L.sub.b 1 L.sub.a29 L.sub.b31 2 L.sub.a34 L.sub.b31 3 L.sub.a29 L.sub.b88 4 L.sub.a34 L.sub.b88 5 L.sub.a29 L.sub.b122 6 L.sub.a34 L.sub.b122 7 L.sub.a29 L.sub.b126 8 L.sub.a34 L.sub.b126 9 L.sub.a29 L.sub.b135 10 L.sub.a34 L.sub.b135 11 L.sub.a42 L.sub.b31 12 L.sub.a45 L.sub.b31 13 L.sub.a42 L.sub.b88 14 L.sub.a45 L.sub.b88 15 L.sub.a42 L.sub.b122 16 L.sub.a45 L.sub.b122 17 L.sub.a42 L.sub.b126 18 L.sub.a45 L.sub.b126 19 L.sub.a42 L.sub.b135 20 L.sub.a45 L.sub.b135 21 L.sub.a104 L.sub.b31 22 L.sub.a295 L.sub.b31 23 L.sub.a104 L.sub.b88 24 L.sub.a295 L.sub.b88 25 L.sub.a104 L.sub.b122 26 L.sub.a295 L.sub.b122 27 L.sub.a104 L.sub.b126 28 L.sub.a295 L.sub.b126 29 L.sub.a104 L.sub.b135 30 L.sub.a295 L.sub.b135 31 L.sub.a364 L.sub.b31 32 L.sub.a368 L.sub.b31 33 L.sub.a364 L.sub.b88 34 L.sub.a368 L.sub.b88 35 L.sub.a364 L.sub.b122 36 L.sub.a368 L.sub.b122 37 L.sub.a364 L.sub.b126 38 L.sub.a368 L.sub.b126 39 L.sub.a364 L.sub.b135 40 L.sub.a368 L.sub.b135 41 L.sub.a372 L.sub.b31 42 L.sub.a374 L.sub.b31 43 L.sub.a372 L.sub.b88 44 L.sub.a374 L.sub.b88 45 L.sub.a372 L.sub.b122 46 L.sub.a374 L.sub.b122 47 L.sub.a372 L.sub.b126 48 L.sub.a374 L.sub.b126 49 L.sub.a372 L.sub.b135 50 L.sub.a374 L.sub.b135 51 L.sub.a418 L.sub.b31 52 L.sub.a420 L.sub.b31 53 L.sub.a418 L.sub.b88 54 L.sub.a420 L.sub.b88 55 L.sub.a418 L.sub.b122 56 L.sub.a420 L.sub.b122 57 L.sub.a418 L.sub.b126 58 L.sub.a420 L.sub.b126 59 L.sub.a418 L.sub.b135 60 L.sub.a420 L.sub.b135 61 L.sub.a418 L.sub.b89 62 L.sub.a420 L.sub.b89 63 L.sub.a418 L.sub.b122 64 L.sub.a420 L.sub.b122 65 L.sub.a418 L.sub.b139 66 L.sub.a420 L.sub.b139 67 L.sub.a422 L.sub.b31 68 L.sub.a500 L.sub.b31 69 L.sub.a422 L.sub.b88 70 L.sub.a500 L.sub.b88 71 L.sub.a422 L.sub.b122 72 L.sub.a500 L.sub.b122 73 L.sub.a422 L.sub.b126 74 L.sub.a500 L.sub.b126 75 L.sub.a422 L.sub.b135 76 L.sub.a500 L.sub.b135 77 L.sub.a422 L.sub.b89 78 L.sub.a500 L.sub.b89 79 L.sub.a422 L.sub.b122 80 L.sub.a500 L.sub.b122 81 L.sub.a422 L.sub.b139 82 L.sub.a500 L.sub.b139 83 L.sub.a502 L.sub.b31 84 L.sub.a504 L.sub.b31 85 L.sub.a502 L.sub.b88 86 L.sub.a504 L.sub.b88 87 L.sub.a502 L.sub.b122 88 L.sub.a504 L.sub.b122 89 L.sub.a502 L.sub.b126 90 L.sub.a504 L.sub.b126 91 L.sub.a502 L.sub.b135 92 L.sub.a504 L.sub.b135 93 L.sub.a502 L.sub.b89 94 L.sub.a504 L.sub.b89 95 L.sub.a502 L.sub.b122 96 L.sub.a504 L.sub.b122 97 L.sub.a502 L.sub.b139 98 L.sub.a504 L.sub.b139 99 L.sub.a505 L.sub.b31 100 L.sub.a516 L.sub.b31 101 L.sub.a505 L.sub.b88 102 L.sub.a516 L.sub.b88 103 L.sub.a505 L.sub.b122 104 L.sub.a516 L.sub.b122 105 L.sub.a505 L.sub.b126 106 L.sub.a516 L.sub.b126 107 L.sub.a505 L.sub.b135 108 L.sub.a516 L.sub.b135 109 L.sub.a505 L.sub.b89 110 L.sub.a516 L.sub.b89 111 L.sub.a505 L.sub.b122 112 L.sub.a516 L.sub.b122 113 L.sub.a505 L.sub.b139 114 L.sub.a516 L.sub.b139 115 L.sub.a520 L.sub.b31 116 L.sub.a530 L.sub.b31 117 L.sub.a520 L.sub.b88 118 L.sub.a530 L.sub.b88 119 L.sub.a520 L.sub.b122 120 L.sub.a530 L.sub.b122 121 L.sub.a520 L.sub.b126 122 L.sub.a530 L.sub.b126 123 L.sub.a520 L.sub.b135 124 L.sub.a530 L.sub.b135 125 L.sub.a520 L.sub.b89 126 L.sub.a530 L.sub.b89 127 L.sub.a520 L.sub.b122 128 L.sub.a530 L.sub.b122 129 L.sub.a520 L.sub.b139 130 L.sub.a530 L.sub.b139 131 L.sub.a534 L.sub.b31 132 L.sub.a575 L.sub.b31 133 L.sub.a534 L.sub.b88 134 L.sub.a575 L.sub.b88 135 L.sub.a534 L.sub.b122 136 L.sub.a575 L.sub.b122 137 L.sub.a534 L.sub.b126 138 L.sub.a575 L.sub.b126 139 L.sub.a534 L.sub.b135 140 L.sub.a575 L.sub.b135 141 L.sub.a534 L.sub.b89 142 L.sub.a575 L.sub.b89 143 L.sub.a534 L.sub.b122 144 L.sub.a575 L.sub.b122 145 L.sub.a534 L.sub.b139 146 L.sub.a575 L.sub.b139 147 L.sub.a579 L.sub.b31 148 L.sub.a701 L.sub.b31 149 L.sub.a579 L.sub.b88 150 L.sub.a701 L.sub.b88 151 L.sub.a579 L.sub.b122 152 L.sub.a701 L.sub.b122 153 L.sub.a579 L.sub.b126 154 L.sub.a701 L.sub.b126 155 L.sub.a579 L.sub.b135 156 L.sub.a701 L.sub.b135 157 L.sub.a579 L.sub.b89 158 L.sub.a701 L.sub.b89 159 L.sub.a579 L.sub.b122 160 L.sub.a701 L.sub.b122 161 L.sub.a579 L.sub.b139 162 L.sub.a701 L.sub.b139 163 L.sub.a713 L.sub.b31 164 L.sub.a679 L.sub.b31 165 L.sub.a713 L.sub.b88 166 L.sub.a679 L.sub.b88 167 L.sub.a713 L.sub.b122 168 L.sub.a679 L.sub.b122 169 L.sub.a713 L.sub.b126 170 L.sub.a679 L.sub.b126 171 L.sub.a713 L.sub.b135 172 L.sub.a679 L.sub.b135 173 L.sub.a713 L.sub.b89 174 L.sub.a679 L.sub.b89 175 L.sub.a713 L.sub.b122 176 L.sub.a679 L.sub.b122 177 L.sub.a713 L.sub.b139 178 L.sub.a679 L.sub.b139 179 L.sub.a690 L.sub.b31 180 L.sub.a423 L.sub.b31 181 L.sub.a690 L.sub.b88 182 L.sub.a423 L.sub.b88 183 L.sub.a690 L.sub.b122 184 L.sub.a423 L.sub.b122 185 L.sub.a690 L.sub.b126 186 L.sub.a423 L.sub.b126 187 L.sub.a690 L.sub.b135 188 L.sub.a423 L.sub.b135 189 L.sub.a690 L.sub.b89 190 L.sub.a423 L.sub.b89 191 L.sub.a690 L.sub.b122 192 L.sub.a423 L.sub.b122 193 L.sub.a690 L.sub.b139 194 L.sub.a423 L.sub.b139 195 L.sub.a425 L.sub.b31 196 L.sub.a472 L.sub.b31 197 L.sub.a425 L.sub.b88 198 L.sub.a472 L.sub.b88 199 L.sub.a425 L.sub.b122 200 L.sub.a472 L.sub.b122 201 L.sub.a425 L.sub.b126 202 L.sub.a472 L.sub.b126 203 L.sub.a425 L.sub.b135 204 L.sub.a472 L.sub.b135 205 L.sub.a425 L.sub.b89 206 L.sub.a472 L.sub.b89 207 L.sub.a425 L.sub.b122 208 L.sub.a472 L.sub.b122 209 L.sub.a425 L.sub.b139 210 L.sub.a472 L.sub.b139 211 L.sub.a506 L.sub.b31 212 L.sub.a536 L.sub.b31 213 L.sub.a506 L.sub.b88 214 L.sub.a536 L.sub.b88 215 L.sub.a506 L.sub.b122 216 L.sub.a536 L.sub.b122 217 L.sub.a506 L.sub.b126 218 L.sub.a536 L.sub.b126 219 L.sub.a506 L.sub.b135 220 L.sub.a536 L.sub.b135 221 L.sub.a506 L.sub.b89 222 L.sub.a536 L.sub.b89 223 L.sub.a506 L.sub.b122 224 L.sub.a536 L.sub.b122 225 L.sub.a506 L.sub.b139 226 L.sub.a536 L.sub.b139 227 L.sub.a559 L.sub.b31 228 L.sub.a534 L.sub.b31 229 L.sub.a559 L.sub.b88 230 L.sub.a534 L.sub.b88 231 L.sub.a559 L.sub.b122 232 L.sub.a534 L.sub.b122 233 L.sub.a559 L.sub.b126 234 L.sub.a534 L.sub.b126 235 L.sub.a559 L.sub.b135 236 L.sub.a534 L.sub.b135 237 L.sub.a559 L.sub.b89 238 L.sub.a534 L.sub.b89 239 L.sub.a559 L.sub.b122 240 L.sub.a534 L.sub.b122 241 L.sub.a559 L.sub.b139 242 L.sub.a534 L.sub.b139 243 L.sub.a537 L.sub.b31 244 L.sub.a587 L.sub.b31 245 L.sub.a537 L.sub.b88 246 L.sub.a587 L.sub.b88 247 L.sub.a537 L.sub.b122 248 L.sub.a587 L.sub.b122 249 L.sub.a537 L.sub.b126 250 L.sub.a587 L.sub.b126 251 L.sub.a537 L.sub.b135 252 L.sub.a587 L.sub.b135 253 L.sub.a537 L.sub.b89 254 L.sub.a587 L.sub.b89 255 L.sub.a537 L.sub.b122 256 L.sub.a587 L.sub.b122 257 L.sub.a537 L.sub.b139 258 L.sub.a587 L.sub.b139 259 L.sub.a589 L.sub.b31 260 L.sub.a543 L.sub.b31 261 L.sub.a589 L.sub.b88 262 L.sub.a543 L.sub.b88 263 L.sub.a589 L.sub.b122 264 L.sub.a543 L.sub.b122 265 L.sub.a589 L.sub.b126 266 L.sub.a543 L.sub.b126 267 L.sub.a589 L.sub.b135 268 L.sub.a543 L.sub.b135 269 L.sub.a589 L.sub.b89 270 L.sub.a543 L.sub.b89 271 L.sub.a589 L.sub.b122 272 L.sub.a543 L.sub.b122 273 L.sub.a589 L.sub.b139 274 L.sub.a543 L.sub.b139 275 L.sub.a592 L.sub.b31 276 L.sub.a622 L.sub.b31 277 L.sub.a592 L.sub.b88 278 L.sub.a622 L.sub.b88 279 L.sub.a592 L.sub.b122 280 L.sub.a622 L.sub.b122 281 L.sub.a592 L.sub.b126 282 L.sub.a622 L.sub.b126 283 L.sub.a592 L.sub.b135 284 L.sub.a622 L.sub.b135 285 L.sub.a592 L.sub.b89 286 L.sub.a622 L.sub.b89 287 L.sub.a592 L.sub.b122 288 L.sub.a622 L.sub.b122 289 L.sub.a592 L.sub.b139 290 L.sub.a622 L.sub.b139 291 L.sub.a624 L.sub.b31 292 L.sub.a635 L.sub.b31 293 L.sub.a624 L.sub.b88 294 L.sub.a635 L.sub.b88 295 L.sub.a624 L.sub.b122 296 L.sub.a635 L.sub.b122 297 L.sub.a624 L.sub.b126 298 L.sub.a635 L.sub.b126 299 L.sub.a624 L.sub.b135 300 L.sub.a635 L.sub.b135 301 L.sub.a624 L.sub.b89 302 L.sub.a635 L.sub.b89 303 L.sub.a624 L.sub.b122 304 L.sub.a635 L.sub.b122 305 L.sub.a624 L.sub.b139 306 L.sub.a635 L.sub.b139 307 L.sub.a630 L.sub.b31 308 L.sub.a654 L.sub.b31 309 L.sub.a630 L.sub.b88 310 L.sub.a654 L.sub.b88 311 L.sub.a630 L.sub.b122 312 L.sub.a654 L.sub.b122 313 L.sub.a630 L.sub.b126 314 L.sub.a654 L.sub.b126 315 L.sub.a630 L.sub.b135 316 L.sub.a654 L.sub.b135 317 L.sub.a630 L.sub.b89 318 L.sub.a654 L.sub.b89 319 L.sub.a630 L.sub.b122 320 L.sub.a654 L.sub.b122 321 L.sub.a630 L.sub.b139 322 L.sub.a654 L.sub.b139 323 L.sub.a597 L.sub.b31 324 L.sub.a701 L.sub.b31 325 L.sub.a597 L.sub.b88 326 L.sub.a701 L.sub.b88 327 L.sub.a597 L.sub.b122 328 L.sub.a701 L.sub.b122 329 L.sub.a597 L.sub.b126 330 L.sub.a701 L.sub.b126 331 L.sub.a597 L.sub.b135 332 L.sub.a701 L.sub.b135 333 L.sub.a597 L.sub.b89 334 L.sub.a701 L.sub.b89 335 L.sub.a597 L.sub.b122 336 L.sub.a701 L.sub.b122 337 L.sub.a597 L.sub.b139 338 L.sub.a701 L.sub.b139 339 L.sub.a704 L.sub.b31 340 L.sub.a706 L.sub.b31 341 L.sub.a704 L.sub.b88 342 L.sub.a706 L.sub.b88 343 L.sub.a704 L.sub.b122 344 L.sub.a706 L.sub.b122 345 L.sub.a704 L.sub.b126 346 L.sub.a706 L.sub.b126 347 L.sub.a704 L.sub.b135 348 L.sub.a706 L.sub.b135 349 L.sub.a704 L.sub.b89 350 L.sub.a706 L.sub.b89 351 L.sub.a704 L.sub.b122 352 L.sub.a706 L.sub.b122 353 L.sub.a704 L.sub.b139 354 L.sub.a706 L.sub.b139 355 L.sub.a707 L.sub.b31 356 L.sub.a713 L.sub.b31 357 L.sub.a707 L.sub.b88 358 L.sub.a713 L.sub.b88 359 L.sub.a707 L.sub.b122 360 L.sub.a713 L.sub.b122 361 L.sub.a707 L.sub.b126 362 L.sub.a713 L.sub.b126 363 L.sub.a707 L.sub.b135 364 L.sub.a713 L.sub.b135 365 L.sub.a707 L.sub.b89 366 L.sub.a713 L.sub.b89 367 L.sub.a707 L.sub.b122 368 L.sub.a713 L.sub.b122 369 L.sub.a707 L.sub.b139 370 L.sub.a713 L.sub.b139 371 L.sub.a716 L.sub.b31 372 L.sub.a720 L.sub.b31 373 L.sub.a716 L.sub.b88 374 L.sub.a720 L.sub.b88 375 L.sub.a716 L.sub.b122 376 L.sub.a720 L.sub.b122 377 L.sub.a716 L.sub.b126 378 L.sub.a720 L.sub.b126 379 L.sub.a716 L.sub.b135 380 L.sub.a720 L.sub.b135 381 L.sub.a716 L.sub.b89 382 L.sub.a720 L.sub.b89 383 L.sub.a716 L.sub.b122 384 L.sub.a720 L.sub.b122 385 L.sub.a716 L.sub.b139 386 L.sub.a720 L.sub.b139 387 L.sub.a679 L.sub.b31 388 L.sub.a682 L.sub.b31 389 L.sub.a679 L.sub.b88 390 L.sub.a682 L.sub.b88 391 L.sub.a679 L.sub.b122 392 L.sub.a682 L.sub.b122 393 L.sub.a679 L.sub.b126 394 L.sub.a682 L.sub.b126 395 L.sub.a679 L.sub.b135 396 L.sub.a682 L.sub.b135 397 L.sub.a679 L.sub.b89 398 L.sub.a682 L.sub.b89 399 L.sub.a679 L.sub.b122 400 L.sub.a682 L.sub.b122 401 L.sub.a679 L.sub.b139 402 L.sub.a682 L.sub.b139 403 L.sub.a684 L.sub.b31 404 L.sub.a685 L.sub.b31 405 L.sub.a684 L.sub.b88 406 L.sub.a685 L.sub.b88 407 L.sub.a684 L.sub.b122 408 L.sub.a685 L.sub.b122 409 L.sub.a684 L.sub.b126 410 L.sub.a685 L.sub.b126 411 L.sub.a684 L.sub.b135 412 L.sub.a685 L.sub.b135 413 L.sub.a684 L.sub.b89 414 L.sub.a685 L.sub.b89 415 L.sub.a684 L.sub.b122 416 L.sub.a685 L.sub.b122 417 L.sub.a684 L.sub.b139 418 L.sub.a685 L.sub.b139 419 L.sub.a690 L.sub.b31 420 L.sub.a692 L.sub.b31 421 L.sub.a690 L.sub.b88 422 L.sub.a692 L.sub.b88 423 L.sub.a690 L.sub.b122 424 L.sub.a692 L.sub.b122 425 L.sub.a690 L.sub.b126 426 L.sub.a692 L.sub.b126 427 L.sub.a690 L.sub.b135 428 L.sub.a692 L.sub.b135 429 L.sub.a690 L.sub.b89 430 L.sub.a692 L.sub.b89 431 L.sub.a690 L.sub.b122 432 L.sub.a692 L.sub.b122 433 L.sub.a690 L.sub.b139 434 L.sub.a692 L.sub.b139 435 L.sub.a695 L.sub.b31 436 L.sub.a697 L.sub.b31 437 L.sub.a695 L.sub.b88 438 L.sub.a697 L.sub.b88 439 L.sub.a695 L.sub.b122 440 L.sub.a697 L.sub.b122 441 L.sub.a695 L.sub.b126 442 L.sub.a697 L.sub.b126 443 L.sub.a695 L.sub.b135 444 L.sub.a697 L.sub.b135 445 L.sub.a695 L.sub.b89 446 L.sub.a697 L.sub.b89 447 L.sub.a695 L.sub.b122 448 L.sub.a697 L.sub.b122 449 L.sub.a695 L.sub.b139 450 L.sub.a697 L.sub.b139 451 L.sub.a698 L.sub.b31 452 L.sub.a733 L.sub.b31 453 L.sub.a698 L.sub.b88 454 L.sub.a733 L.sub.b88 455 L.sub.a695 L.sub.b122 456 L.sub.a733 L.sub.b122 457 L.sub.a698 L.sub.b126 458 L.sub.a733 L.sub.b126 459 L.sub.a698 L.sub.b135 460 L.sub.a733 L.sub.b135 461 L.sub.a698 L.sub.b89 462 L.sub.a733 L.sub.b89 463 L.sub.a695 L.sub.b122 464 L.sub.a733 L.sub.b122 465 L.sub.a695 L.sub.b139 466 L.sub.a733 L.sub.b139 467 L.sub.a755 L.sub.b31 468 L.sub.a777 L.sub.b31 469 L.sub.a755 L.sub.b88 470 L.sub.a777 L.sub.b88 471 L.sub.a755 L.sub.b122 472 L.sub.a777 L.sub.b122 473 L.sub.a755 L.sub.b126 474 L.sub.a777 L.sub.b126 475 L.sub.a755 L.sub.b135 476 L.sub.a777 L.sub.b135 477 L.sub.a755 L.sub.b89 478 L.sub.a777 L.sub.b89 479 L.sub.a755 L.sub.b122 480 L.sub.a777 L.sub.b122 481 L.sub.a755 L.sub.b139 482 L.sub.a777 L.sub.b139 483 L.sub.a788 L.sub.b31 484 L.sub.a780 L.sub.b31 485 L.sub.a788 L.sub.b88 486 L.sub.a780 L.sub.b88 487 L.sub.a788 L.sub.b122 488 L.sub.a780 L.sub.b122 489 L.sub.a788 L.sub.b126 490 L.sub.a780 L.sub.b126 491 L.sub.a788 L.sub.b135 492 L.sub.a780 L.sub.b135 493 L.sub.a788 L.sub.b89 494 L.sub.a780 L.sub.b89 495 L.sub.a788 L.sub.b122 496 L.sub.a780 L.sub.b122 497 L.sub.a788 L.sub.b139 498 L.sub.a780 L.sub.b139 499 L.sub.a791 L.sub.b31 500 L.sub.a793 L.sub.b31 501 L.sub.a791 L.sub.b88 502 L.sub.a793 L.sub.b88 503 L.sub.a791 L.sub.b122 504 L.sub.a793 L.sub.b122 505 L.sub.a791 L.sub.b126 506 L.sub.a793 L.sub.b126 507 L.sub.a791 L.sub.b135 508 L.sub.a793 L.sub.b135 509 L.sub.a791 L.sub.b89 510 L.sub.a793 L.sub.b89 511 L.sub.a791 L.sub.b122 512 L.sub.a793 L.sub.b122 513 L.sub.a791 L.sub.b139 514 L.sub.a793 L.sub.b139 515 L.sub.a794 L.sub.b31 516 L.sub.a795 L.sub.b31 517 L.sub.a794 L.sub.b88 518 L.sub.a795 L.sub.b88 519 L.sub.a794 L.sub.b122 520 L.sub.a795 L.sub.b122 521 L.sub.a794 L.sub.b126 522 L.sub.a795 L.sub.b126 523 L.sub.a794 L.sub.b135 524 L.sub.a795 L.sub.b135 525 L.sub.a794 L.sub.b89 526 L.sub.a795 L.sub.b89 527 L.sub.a794 L.sub.b122 528 L.sub.a795 L.sub.b122 529 L.sub.a794 L.sub.b139 530 L.sub.a795 L.sub.b139 531 L.sub.a272 L.sub.b31 532 L.sub.a918 L.sub.b31 533 L.sub.a272 L.sub.b88 534 L.sub.a918 L.sub.b88 535 L.sub.a272 L.sub.b122 536 L.sub.a918 L.sub.b122 537 L.sub.a272 L.sub.b126 538 L.sub.a918 L.sub.b126 669 L.sub.a1235 L.sub.b122 670 L.sub.a1235. L.sub.b126 Compound 539 to Compound 668 have the general formula of Ir(L.sub.a)(L.sub.c).sub.2, wherein two L.sub.c are identical, and L.sub.a and L.sub.c are selected from structures listed in the following table, respectively: TABLE-US-00008 Compound No. L.sub.a L.sub.c Compound No. L.sub.a L.sub.c 539 L.sub.a1 L.sub.c1 540 L.sub.a1 L.sub.c3 541 L.sub.a1 L.sub.C4 542 L.sub.a1 L.sub.c11 543 L.sub.a1 L.sub.C12 544 L.sub.a1 L.sub.C13 545 L.sub.a1 L.sub.C15 546 L.sub.a1 L.sub.C16 547 L.sub.a1 L.sub.c20 548 L.sub.a1 L.sub.c21 549 L.sub.a1 L.sub.c22 550 L.sub.a1 L.sub.C23 551 L.sub.a1 L.sub.c36 552 L.sub.a1 L.sub.c37 553 L.sub.a1 L.sub.C38 554 L.sub.a1 L.sub.c39 555 L.sub.a1 L.sub.c42 556 L.sub.a1 L.sub.C43 557 L.sub.a1 L.sub.C44 558 L.sub.a1 L.sub.c47 559 L.sub.a1 L.sub.c232 560 L.sub.a1 L.sub.c233 561 L.sub.a1 L.sub.c235 562 L.sub.a1 L.sub.c251 563 L.sub.a1 L.sub.c261 564 L.sub.a1 L.sub.c271 565 L.sub.a1 L.sub.c308 566 L.sub.a1 L.sub.c309 567 L.sub.a1 L.sub.c316 568 L.sub.a1 L.sub.c319 569 L.sub.a1 L.sub.c320 570 L.sub.a1 L.sub.c321 571 L.sub.a21 L.sub.c1 572 L.sub.a21 L.sub.C3 573 L.sub.a21 L.sub.c4 574 L.sub.a21 L.sub.c11 575 L.sub.a21 L.sub.C12 576 L.sub.a21 L.sub.C13 577 L.sub.a21 L.sub.c15 578 L.sub.a21 L.sub.c16 579 L.sub.a21 L.sub.C20 580 L.sub.a21 L.sub.c21 581 L.sub.a21 L.sub.C22 582 L.sub.a21 L.sub.C23 583 L.sub.a21 L.sub.C36 584 L.sub.a21 L.sub.C37 585 L.sub.a21 L.sub.C38 586 L.sub.a21 L.sub.c39 587 L.sub.a21 L.sub.c42 588 L.sub.a21 L.sub.C43 589 L.sub.a21 L.sub.C44 590 L.sub.a21 L.sub.c47 591 L.sub.a21 L.sub.C232 592 L.sub.a21 L.sub.C233 593 L.sub.a21 L.sub.C235 594 L.sub.a21 L.sub.C251 595 L.sub.a21 L.sub.C261 596 L.sub.a21 L.sub.C271 597 L.sub.a21 L.sub.c308 598 L.sub.a21 L.sub.c309 599 L.sub.a21 L.sub.c316 600 L.sub.a21 L.sub.c319 601 L.sub.a21 L.sub.c320 602 L.sub.a21 L.sub.c321 603 L.sub.a1238 L.sub.c1 604 L.sub.a1238 L.sub.c3 605 L.sub.a1238 L.sub.c4 606 L.sub.a1238 L.sub.C11 607 L.sub.a1238 L.sub.C12 608 L.sub.a1238 L.sub.C13 609 L.sub.a1238 L.sub.C15 610 L.sub.a1238 L.sub.C16 611 L.sub.a1238 L.sub.c20 612 L.sub.a1238 L.sub.c21 613 L.sub.a1238 L.sub.c22 614 L.sub.a1238 L.sub.C23 615 L.sub.a1238 L.sub.c36 616 L.sub.a1238 L.sub.c37 617 L.sub.a1238 L.sub.C38 618 L.sub.a1238 L.sub.c39 619 L.sub.a1238 L.sub.c42 620 L.sub.a1238 L.sub.C43 621 L.sub.a1238 L.sub.C44 622 L.sub.a1238 L.sub.c47 623 L.sub.a1238 L.sub.c232 624 L.sub.a1238 L.sub.c233 625 L.sub.a1238 L.sub.C235 626 L.sub.a1238 L.sub.C251 627 L.sub.a1238 L.sub.C261 628 L.sub.a1238 L.sub.C271 629 L.sub.a1238 L.sub.c308 630 L.sub.a1238 L.sub.c309 631 L.sub.a1238 L.sub.c316 632 L.sub.a1238 L.sub.c319 633 L.sub.a1238 L.sub.c320 634 L.sub.a1238 L.sub.c321 635 L.sub.a1240 L.sub.c1 636 L.sub.a1240 L.sub.c3 637 L.sub.a1240 L.sub.c4 638 L.sub.a1240 L.sub.e11 639 L.sub.a1240 L.sub.C12 640 L.sub.a1240 L.sub.C13 641 L.sub.a1240 L.sub.C15 642 L.sub.a1240 L.sub.C16 643 L.sub.a1240 L.sub.c20 644 L.sub.a1240 L.sub.c21 645 L.sub.a1240 L.sub.c22 646 L.sub.a1240 L.sub.c23 647 L.sub.a1240 L.sub.c36 648 L.sub.a1240 L.sub.c37 649 L.sub.a1240 L.sub.C38 650 L.sub.a1240 L.sub.c39 651 L.sub.a1240 L.sub.c42 652 L.sub.a1240 L.sub.C43 653 L.sub.a1240 L.sub.C44 654 L.sub.a1240 L.sub.C47 655 L.sub.a1240 L.sub.C232 656 L.sub.a1240 L.sub.C233 657 L.sub.a1240 L.sub.C235 658 L.sub.a1240 L.sub.C251 659 L.sub.a1240 L.sub.C261 660 L.sub.a1240 L.sub.C271 661 L.sub.a1240 L.sub.c308 662 L.sub.a1240 L.sub.c309 663 L.sub.a1240 L.sub.c316 664 L.sub.a1240 L.sub.c319 665 L.sub.a1240 L.sub.c320 666 L.sub.a1240 L.sub.c321 667 L.sub.a1229 L.sub.C232 668 L.sub.a1232 L.sub.c232 .

15. An electroluminescent device, comprising: an anode, a cathode, and an organic layer disposed between the anode and the cathode, wherein the organic layer comprises the metal complex of claim 1.

16. The electroluminescent device of claim 15, wherein the organic layer is a light-emitting layer, and the metal complex is a light-emitting material.

17. The electroluminescent device of claim 15, wherein the electroluminescent device emits red light, yellow light, green light or white light.

18. The electroluminescent device of claim 16, wherein the light-emitting layer further comprises at least one host material; preferably, the at least one host material comprises at least one chemical group selected from the group consisting of: benzene, pyridine, pyrimidine, triazine, carbazole, azacarbazole, indolocarbazole, dibenzothiophene, azadibenzothiophene, dibenzofuran, azadibenzofuran, dibenzoselenophene, triphenylene, azatriphenylene, fluorene, silafluorene, naphthalene, quinoline, isoquinoline, quinazoline, quinoxaline, phenanthrene, azaphenanthrene, and combinations thereof.

19. A compound composition, comprising the metal complex of claim 1.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0024] FIG. 1 is a schematic diagram of an organic light-emitting apparatus that may comprise a metal complex and a compound composition disclosed herein.

[0025] FIG. 2 is a schematic diagram of another organic light-emitting apparatus that may comprise a metal complex and a compound composition disclosed herein.

DETAILED DESCRIPTION

[0026] OLEDs can be fabricated on various types of substrates such as glass, plastic, and metal foil. FIG. 1 schematically shows an organic light-emitting device 100 without limitation. The figures are not necessarily drawn to scale. Some of the layers in the figures can also be omitted as needed. Device 100 may include a substrate 101, an anode 110, a hole injection layer 120, a hole transport layer 130, an electron blocking layer 140, an emissive layer 150, a hole blocking layer 160, an electron transport layer 170, an electron injection layer 180 and a cathode 190. Device 100 may be fabricated by depositing the layers described in order. The properties and functions of these various layers, as well as example materials, are described in more detail in U.S. Pat. No. 7,279,704 at cols. 6-10, the contents of which are incorporated by reference herein in its entirety.

[0027] More examples for each of these layers are available. For example, a flexible and transparent substrate-anode combination is disclosed in U.S. Pat. No. 5,844,363, which is incorporated by reference herein in its entirety. An example of a p-doped hole transport layer is m-MTDATA doped with F4-TCNQ at a molar ratio of 50:1, as disclosed in U.S. Pat. Application Publication No. 2003/0230980, which is incorporated by reference herein in its entirety. Examples of host materials are disclosed in U.S. Pat. No. 6,303,238 to Thompson et al., which is incorporated by reference herein in its entirety. An example of an n-doped electron transport layer is BPhen doped with Li at a molar ratio of 1:1, as disclosed in U.S. Pat. Application Publication No. 2003/0230980, which is incorporated by reference herein in its entirety. U.S. Pat. Nos. 5,703,436 and 5,707,745, which are incorporated by reference herein in their entireties, disclose examples of cathodes including composite cathodes having a thin layer of metal such as Mg:Ag with an overlying transparent, electrically-conductive, sputter-deposited ITO layer. The theory and use of blocking layers are described in more detail in U.S. Pat. No. 6,097,147 and U.S. Pat. Application Publication No. 2003/0230980, which are incorporated by reference herein in their entireties. Examples of injection layers are provided in U.S. Pat. Application Publication No. 2004/0174116, which is incorporated by reference herein in its entirety. A description of protective layers may be found in U.S. Pat. Application Publication No. 2004/0174116, which is incorporated by reference herein in its entirety.

[0028] The layered structure described above is provided by way of non-limiting examples. Functional OLEDs may be achieved by combining the various layers described in different ways, or layers may be omitted entirely. It may also include other layers not specifically described. Within each layer, a single material or a mixture of multiple materials can be used to achieve optimum performance. Any functional layer may include several sublayers. For example, the emissive layer may have two layers of different emitting materials to achieve desired emission spectrum.

[0029] In one embodiment, an OLED may be described as having an “organic layer” disposed between a cathode and an anode. This organic layer may include a single layer or multiple layers.

[0030] An OLED can be encapsulated by a barrier layer. FIG. 2 schematically shows an organic light emitting device 200 without limitation. FIG. 2 differs from FIG. 1 in that the organic light emitting device include a barrier layer 102, which is above the cathode 190, to protect it from harmful species from the environment such as moisture and oxygen. Any material that can provide the barrier function can be used as the barrier layer such as glass or organic-inorganic hybrid layers. The barrier layer should be placed directly or indirectly outside of the OLED device. Multilayer thin film encapsulation was described in U.S. Pat. No. 7,968,146, which is incorporated by reference herein in its entirety.

[0031] Devices fabricated in accordance with embodiments of the present disclosure can be incorporated into a wide variety of consumer products that have one or more of the electronic component modules (or units) incorporated therein. Some examples of such consumer products include flat panel displays, monitors, medical monitors, televisions, billboards, lights for interior or exterior illumination and/or signaling, heads-up displays, fully or partially transparent displays, flexible displays, smart phones, tablets, phablets, wearable devices, smart watches, laptop computers, digital cameras, camcorders, viewfinders, micro-displays, 3-D displays, vehicles displays, and vehicle tail lights.

[0032] The materials and structures described herein may be used in other organic electronic devices listed above.

[0033] As used herein, “top” means furthest away from the substrate, while “bottom” means closest to the substrate. Where a first layer is described as “disposed over” a second layer, the first layer is disposed further away from the substrate. There may be other layers between the first and second layers, unless it is specified that the first layer is “in contact with” the second layer. For example, a cathode may be described as “disposed over” an anode, even though there are various organic layers in between.

[0034] As used herein, “solution processible” means capable of being dissolved, dispersed, or transported in and/or deposited from a liquid medium, either in solution or suspension form.

[0035] A ligand may be referred to as “photoactive” when it is believed that the ligand directly contributes to the photoactive properties of an emissive material. A ligand may be referred to as “ancillary” when it is believed that the ligand does not contribute to the photoactive properties of an emissive material, although an ancillary ligand may alter the properties of a photoactive ligand.

[0036] It is believed that the internal quantum efficiency (IQE) of fluorescent OLEDs can exceed the 25% spin statistics limit through delayed fluorescence. As used herein, there are two types of delayed fluorescence, i.e. P-type delayed fluorescence and E-type delayed fluorescence. P-type delayed fluorescence is generated from triplet-triplet annihilation (TTA).

[0037] On the other hand, E-type delayed fluorescence does not rely on the collision of two triplets, but rather on the transition between the triplet states and the singlet excited states. Compounds that are capable of generating E-type delayed fluorescence are required to have very small singlet-triplet gaps to convert between energy states. Thermal energy can activate the transition from the triplet state back to the singlet state. This type of delayed fluorescence is also known as thermally activated delayed fluorescence (TADF). A distinctive feature of TADF is that the delayed component increases as temperature rises. If the reverse intersystem crossing (RISC) rate is fast enough to minimize the non-radiative decay from the triplet state, the fraction of back populated singlet excited states can potentially reach 75%. The total singlet fraction can be 100%, far exceeding 25% of the spin statistics limit for electrically generated excitons.

[0038] E-type delayed fluorescence characteristics can be found in an exciplex system or in a single compound. Without being bound by theory, it is believed that E-type delayed fluorescence requires the luminescent material to have a small singlet-triplet energy gap (ΔE.sub.S-T). Organic, non-metal containing, donor-acceptor luminescent materials may be able to achieve this. The emission in these materials is generally characterized as a donor-acceptor charge-transfer (CT) type emission. The spatial separation of the HOMO and LUMO in these donor-acceptor type compounds generally results in small ΔE.sub.S-T. These states may involve CT states. Generally, donor-acceptor luminescent materials are constructed by connecting an electron donor moiety such as amino- or carbazole-derivatives and an electron acceptor moiety such as N-containing six-membered aromatic rings.

Definition of Terms of Substituents

[0039] Halogen or halide - as used herein includes fluorine, chlorine, bromine, and iodine.

[0040] Alkyl - as used herein includes both straight and branched chain alkyl groups. Alkyl may be alkyl having 1 to 20 carbon atoms, preferably alkyl having 1 to 12 carbon atoms, and more preferably alkyl having 1 to 6 carbon atoms. Examples of alkyl groups include a methyl group, an ethyl group, a propyl group, an isopropyl group, a n-butyl group, an s-butyl group, an isobutyl group, a t-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, an n-nonyl group, an n-decyl group, an n-undecyl group, an n-dodecyl group, an n-tridecyl group, an n-tetradecyl group, an n-pentadecyl group, an n-hexadecyl group, an n-heptadecyl group, an n-octadecyl group, a neopentyl group, a 1-methylpentyl group, a 2-methylpentyl group, a 1-pentylhexyl group, a 1-butylpentyl group, a 1-heptyloctyl group, and a 3-methylpentyl group. Of the above, preferred are a methyl group, an ethyl group, a propyl group, an isopropyl group, a n-butyl group, an s-butyl group, an isobutyl group, a t-butyl group, an n-pentyl group, a neopentyl group, and an n-hexyl group. Additionally, the alkyl group may be optionally substituted.

[0041] Cycloalkyl - as used herein includes cyclic alkyl groups. The cycloalkyl groups may be those having 3 to 20 ring carbon atoms, preferably those having 4 to 10 carbon atoms. Examples of cycloalkyl include cyclobutyl, cyclopentyl, cyclohexyl, 4-methylcyclohexyl, 4,4-dimethylcylcohexyl, 1-adamantyl, 2-adamantyl, 1-norbornyl, 2-norbornyl, and the like. Of the above, preferred are cyclopentyl, cyclohexyl, 4-methylcyclohexyl, and 4,4-dimethylcylcohexyl. Additionally, the cycloalkyl group may be optionally substituted.

[0042] Heteroalkyl - as used herein, includes a group formed by replacing one or more carbons in an alkyl chain with a hetero-atom(s) selected from the group consisting of a nitrogen atom, an oxygen atom, a sulfur atom, a selenium atom, a phosphorus atom, a silicon atom, a germanium atom, and a boron atom. Heteroalkyl may be those having 1 to 20 carbon atoms, preferably those having 1 to 10 carbon atoms, and more preferably those having 1 to 6 carbon atoms. Examples of heteroalkyl include methoxymethyl, ethoxymethyl, ethoxyethyl, methylthiomethyl, ethylthiomethyl, ethylthioethyl, methoxymethoxymethyl, ethoxymethoxymethyl, ethoxyethoxyethyl, hydroxymethyl, hydroxyethyl, hydroxypropyl, mercaptomethyl, mercaptoethyl, mercaptopropyl, aminomethyl, aminoethyl, aminopropyl, dimethylaminomethyl, trimethylgermanylmethyl, trimethylgermanylethyl, trimethylgermanylisopropyl, dimethylethylgermanylmethyl, dimethylisopropylgermanylmethyl, tert-butyldimethylgermanylmethyl, triethylgermanylmethyl, triethylgermanylethyl, triisopropylgermanylmethyl, triisopropylgermanylethyl, trimethylsilylmethyl, trimethylsilylethyl, trimethylsilylisopropyl, triisopropylsilylmethyl, and triisopropylsilylethyl. Additionally, the heteroalkyl group may be optionally substituted.

[0043] Alkenyl - as used herein includes straight chain, branched chain, and cyclic alkene groups. Alkenyl may be those having 2 to 20 carbon atoms, preferably those having 2 to 10 carbon atoms. Examples of alkenyl include vinyl, 1-propenyl group, 1-butenyl, 2-butenyl, 3-butenyl, 1,3-butandienyl, 1-methylvinyl, styryl, 2,2-diphenylvinyl, 1,2-diphenylvinyl, 1-methylallyl, 1,1-dimethylallyl, 2-methylallyl, 1-phenylallyl, 2-phenylallyl, 3-phenylallyl, 3,3-diphenylallyl, 1,2-dimethylallyl, 1-phenyl-1-butenyl, 3-phenyl-1-butenyl, cyclopentenyl, cyclopentadienyl, cyclohexenyl, cycloheptenyl, cycloheptatrienyl, cyclooctenyl, cyclooctatetraenyl, and norbornenyl. Additionally, the alkenyl group may be optionally substituted.

[0044] Alkynyl - as used herein includes straight chain alkynyl groups. Alkynyl may be those having 2 to 20 carbon atoms, preferably those having 2 to 10 carbon atoms. Examples of alkynyl groups include ethynyl, propynyl, propargyl, 1-butynyl, 2-butynyl, 3-butynyl, 1-pentynyl, 2-pentynyl, 3,3-dimethyl-1-butynyl, 3-ethyl-3-methyl-1-pentynyl, 3,3-diisopropyl-1-pentynyl, phenylethynyl, phenylpropynyl, etc. Of the above, preferred are ethynyl, propynyl, propargyl, 1-butynyl, 2-butynyl, 3-butynyl, 1-pentynyl, and phenylethynyl. Additionally, the alkynyl group may be optionally substituted.

[0045] Aryl or an aromatic group - as used herein includes non-condensed and condensed systems. Aryl may be those having 6 to 30 carbon atoms, preferably those having 6 to 20 carbon atoms, and more preferably those having 6 to 12 carbon atoms. Examples of aryl groups include phenyl, biphenyl, terphenyl, triphenylene, tetraphenylene, naphthalene, anthracene, phenalene, phenanthrene, fluorene, pyrene, chrysene, perylene, and azulene, preferably phenyl, biphenyl, terphenyl, triphenylene, fluorene, and naphthalene. Examples of non-condensed aryl groups include phenyl, biphenyl-2-yl, biphenyl-3-yl, biphenyl-4-yl, p-terphenyl-4-yl, p-terphenyl-3-yl, p-terphenyl-2-yl, m-terphenyl-4-yl, m-terphenyl-3-yl, m-terphenyl-2-yl, o-tolyl, m-tolyl, p-tolyl, p-(2-phenylpropyl)phenyl, 4′-methylbiphenylyl, 4″-t-butyl-p-terphenyl-4-yl, o-cumenyl, m-cumenyl, p-cumenyl, 2,3-xylyl, 3,4-xylyl, 2,5-xylyl, mesityl, and m-quarterphenyl. Additionally, the aryl group may be optionally substituted.

[0046] Heterocyclic groups or heterocycle - as used herein include non-aromatic cyclic groups. Non-aromatic heterocyclic groups include saturated heterocyclic groups having 3 to 20 ring atoms and unsaturated non-aromatic heterocyclic groups having 3 to 20 ring atoms, where at least one ring atom is selected from the group consisting of a nitrogen atom, an oxygen atom, a sulfur atom, a selenium atom, a silicon atom, a phosphorus atom, a germanium atom, and a boron atom. Preferred non-aromatic heterocyclic groups are those having 3 to 7 ring atoms, each of which includes at least one hetero-atom such as nitrogen, oxygen, silicon, or sulfur. Examples of non-aromatic heterocyclic groups include oxiranyl, oxetanyl, tetrahydrofuranyl, tetrahydropyranyl, dioxolanyl, dioxanyl, aziridinyl, dihydropyrrolyl, tetrahydropyrrolyl, piperidinyl, oxazolidinyl, morpholinyl, piperazinyl, oxepinyl, thiepinyl, azepinyl, and tetrahydrosilolyl. Additionally, the heterocyclic group may be optionally substituted.

[0047] Heteroaryl - as used herein, includes non-condensed and condensed hetero-aromatic groups having 1 to 5 hetero-atoms, where at least one hetero-atom is selected from the group consisting of a nitrogen atom, an oxygen atom, a sulfur atom, a selenium atom, a silicon atom, a phosphorus atom, a germanium atom, and a boron atom. A hetero-aromatic group is also referred to as heteroaryl. Heteroaryl may be those having 3 to 30 carbon atoms, preferably those having 3 to 20 carbon atoms, and more preferably those having 3 to 12 carbon atoms. Suitable heteroaryl groups include dibenzothiophene, dibenzofuran, dibenzoselenophene, furan, thiophene, benzofuran, benzothiophene, benzoselenophene, carbazole, indolocarbazole, pyridoindole, pyrrolodipyridine, pyrazole, imidazole, triazole, oxazole, thiazole, oxadiazole, oxatriazole, dioxazole, thiadiazole, pyridine, pyridazine, pyrimidine, pyrazine, triazine, oxazine, oxathiazine, oxadiazine, indole, benzimidazole, indazole, indoxazine, benzoxazole, benzisoxazole, benzothiazole, quinoline, isoquinoline, cinnoline, quinazoline, quinoxaline, naphthyridine, phthalazine, pteridine, xanthene, acridine, phenazine, phenothiazine, benzofuropyridine, furodipyridine, benzothienopyridine, thienodipyridine, benzoselenophenopyridine, and selenophenodipyridine, preferably dibenzothiophene, dibenzofuran, dibenzoselenophene, carbazole, indolocarbazole, imidazole, pyridine, triazine, benzimidazole, 1,2-azaborine, 1,3-azaborine, 1,4-azaborine, borazine, and aza-analogs thereof. Additionally, the heteroaryl group may be optionally substituted.

[0048] Alkoxy - as used herein, is represented by —O—alkyl, —O—cycloalkyl, —O—heteroalkyl, or -O-heterocyclic group. Examples and preferred examples of alkyl, cycloalkyl, heteroalkyl, and heterocyclic groups are the same as those described above. Alkoxy groups may be those having 1 to 20 carbon atoms, preferably those having 1 to 6 carbon atoms. Examples of alkoxy groups include methoxy, ethoxy, propoxy, butoxy, pentyloxy, hexyloxy, cyclopropyloxy, cyclobutyloxy, cyclopentyloxy, cyclohexyloxy, tetrahydrofuranyloxy, tetrahydropyranyloxy, methoxypropyloxy, ethoxyethyloxy, methoxymethyloxy, and ethoxymethyloxy. Additionally, the alkoxy group may be optionally substituted.

[0049] Aryloxy - as used herein, is represented by —O—aryl or —O—heteroaryl. Examples and preferred examples of aryl and heteroaryl are the same as those described above. Aryloxy groups may be those having 6 to 30 carbon atoms, preferably those having 6 to 20 carbon atoms. Examples of aryloxy groups include phenoxy and biphenyloxy. Additionally, the aryloxy group may be optionally substituted.

[0050] Arylalkyl - as used herein, contemplates alkyl substituted with an aryl group. Arylalkyl may be those having 7 to 30 carbon atoms, preferably those having 7 to 20 carbon atoms, and more preferably those having 7 to 13 carbon atoms. Examples of arylalkyl groups include benzyl, 1-phenylethyl, 2-phenylethyl, 1-phenylisopropyl, 2-phenylisopropyl, phenyl-t-butyl, alpha-naphthylmethyl, 1-alpha-naphthylethyl, 2-alpha-naphthylethyl, 1-alpha-naphthylisopropyl, 2-alpha-naphthylisopropyl, beta-naphthylmethyl, 1-beta-naphthylethyl, 2-beta-naphthylethyl, 1-beta-naphthylisopropyl, 2-beta-naphthylisopropyl, p-methylbenzyl, m-methylbenzyl, o-methylbenzyl, p-chlorobenzyl, m-chlorobenzyl, o-chlorobenzyl, p-bromobenzyl, m-bromobenzyl, o-bromobenzyl, p-iodobenzyl, m-iodobenzyl, o-iodobenzyl, p-hydroxybenzyl, m-hydroxybenzyl, o-hydroxybenzyl, p-aminobenzyl, m-aminobenzyl, o-aminobenzyl, p-nitrobenzyl, m-nitrobenzyl, o-nitrobenzyl, p-cyanobenzyl, m-cyanobenzyl, o-cyanobenzyl, 1-hydroxy-2-phenylisopropyl, and 1-chloro-2-phenylisopropyl. Of the above, preferred are benzyl, p-cyanobenzyl, m-cyanobenzyl, o-cyanobenzyl, 1-phenylethyl, 2-phenylethyl, 1-phenylisopropyl, and 2-phenylisopropyl. Additionally, the arylalkyl group may be optionally substituted.

[0051] Alkylsilyl - as used herein, contemplates a silyl group substituted with an alkyl group. Alkylsilyl groups may be those having 3 to 20 carbon atoms, preferably those having 3 to 10 carbon atoms. Examples of alkylsilyl groups include trimethylsilyl, triethylsilyl, methyldiethylsilyl, ethyldimethylsilyl, tripropylsilyl, tributylsilyl, triisopropylsilyl, methyldiisopropylsilyl, dimethylisopropylsilyl, tri-t-butylsilyl, triisobutylsilyl, dimethyl t-butylsilyl, and methyldi-t-butylsilyl. Additionally, the alkylsilyl group may be optionally substituted.

[0052] Arylsilyl - as used herein, contemplates a silyl group substituted with an aryl group. Arylsilyl groups may be those having 6 to 30 carbon atoms, preferably those having 8 to 20 carbon atoms. Examples of arylsilyl groups include triphenylsilyl, phenyldibiphenylylsilyl, diphenylbiphenylsilyl, phenyldiethylsilyl, diphenylethylsilyl, phenyldimethylsilyl, diphenylmethylsilyl, phenyldiisopropylsilyl, diphenylisopropylsilyl, diphenylbutylsilyl, diphenylisobutylsilyl, diphenyl t-butylsilyl. Additionally, the arylsilyl group may be optionally substituted.

[0053] Alkylgermanyl - as used herein contemplates a germanyl substituted with an alkyl group. The alkylgermanyl may be those having 3 to 20 carbon atoms, preferably those having 3 to 10 carbon atoms. Examples of alkylgermanyl include trimethylgermanyl, triethylgermanyl, methyldiethylgermanyl, ethyldimethylgermanyl, tripropylgermanyl, tributylgermanyl, triisopropylgermanyl, methyldiisopropylgermanyl, dimethylisopropylgermanyl, tri-t-butylgermanyl, triisobutylgermanyl, dimethyl-t-butylgermanyl, and methyldi-t-butylgermanyl. Additionally, the alkylgermanyl may be optionally substituted.

[0054] Arylgermanyl - as used herein contemplates a germanyl substituted with at least one aryl group or heteroaryl group. Arylgermanyl may be those having 6 to 30 carbon atoms, preferably those having 8 to 20 carbon atoms. Examples of arylgermanyl include triphenylgermanyl, phenyldibiphenylylgermanyl, diphenylbiphenylgermanyl, phenyldiethylgermanyl, diphenylethylgermanyl, phenyldimethylgermanyl, diphenylmethylgermanyl, phenyldiisopropylgermanyl, diphenylisopropylgermanyl, diphenylbutylgermanyl, diphenylisobutylgermanyl, and diphenyl-t-butylgermanyl. Additionally, the arylgermanyl may be optionally substituted.

[0055] The term “aza” in azadibenzofuran, azadibenzothiophene, etc. means that one or more of C-H groups in the respective aromatic fragment are replaced by a nitrogen atom. For example, azatriphenylene encompasses dibenzo[f,h]quinoxaline, dibenzo[f,h]quinoline and other analogs with two or more nitrogens in the ring system. One of ordinary skill in the art can readily envision other nitrogen analogs of the aza-derivatives described above, and all such analogs are intended to be encompassed by the terms as set forth herein.

[0056] In the present disclosure, unless otherwise defined, when any term of the group consisting of substituted alkyl, substituted cycloalkyl, substituted heteroalkyl, substituted heterocyclic group, substituted arylalkyl, substituted alkoxy, substituted aryloxy, substituted alkenyl, substituted alkynyl, substituted aryl, substituted heteroaryl, substituted alkylsilyl, substituted arylsilyl, substituted alkylgermanyl, substituted arylgermanyl, substituted amino, substituted acyl, substituted carbonyl, a substituted carboxylic acid group, a substituted ester group, substituted sulfinyl, substituted sulfonyl, and substituted phosphino is used, it means that any group of alkyl, cycloalkyl, heteroalkyl, heterocyclic group, arylalkyl, alkoxy, aryloxy, alkenyl, alkynyl, aryl, heteroaryl, alkylsilyl, arylsilyl, alkylgermanyl, arylgermanyl, amino, acyl, carbonyl, a carboxylic acid group, an ester group, sulfinyl, sulfonyl, and phosphino may be substituted with one or more groups selected from the group consisting of deuterium, halogen, unsubstituted alkyl having 1 to 20 carbon atoms, unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, unsubstituted heteroalkyl having 1 to 20 carbon atoms, an unsubstituted heterocyclic group having 3 to 20 ring atoms, unsubstituted arylalkyl having 7 to 30 carbon atoms, unsubstituted alkoxy having 1 to 20 carbon atoms, unsubstituted aryloxy having 6 to 30 carbon atoms, unsubstituted alkenyl having 2 to 20 carbon atoms, unsubstituted alkynyl having 2 to 20 carbon atoms, unsubstituted aryl having 6 to 30 carbon atoms, unsubstituted heteroaryl having 3 to 30 carbon atoms, unsubstituted alkylsilyl having 3 to 20 carbon atoms, unsubstituted arylsilyl group having 6 to 20 carbon atoms, unsubstituted alkylgermanyl group having 3 to 20 carbon atoms, unsubstituted arylgermanyl group having 6 to 20 carbon atoms, unsubstituted amino having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a sulfanyl group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof.

[0057] It is to be understood that when a molecular fragment is described as being a substituent or otherwise attached to another moiety, its name may be written as if it were a fragment (e.g. phenyl, phenylene, naphthyl, dibenzofuryl) or as if it were the whole molecule (e.g. benzene, naphthalene, dibenzofuran). As used herein, these different ways of designating a substituent or an attached fragment are considered to be equivalent.

[0058] In the compounds mentioned in the present disclosure, hydrogen atoms may be partially or fully replaced by deuterium. Other atoms such as carbon and nitrogen may also be replaced by their other stable isotopes. The replacement by other stable isotopes in the compounds may be preferred due to its enhancements of device efficiency and stability.

[0059] In the compounds mentioned in the present disclosure, multiple substitutions refer to a range that includes di-substitutions, up to the maximum available substitutions. When substitution in the compounds mentioned in the present disclosure represents multiple substitutions (including di-, tri-, and tetra-substitutions etc.), that means the substituent may exist at a plurality of available substitution positions on its linking structure, the substituents present at a plurality of available substitution positions may have the same structure or different structures.

[0060] In the compounds mentioned in the present disclosure, adjacent substituents in the compounds cannot be joined to form a ring unless otherwise explicitly defined, for example, adjacent substituents can be optionally joined to form a ring. In the compounds mentioned in the present disclosure, the expression that adjacent substituents can be optionally joined to form a ring includes a case where adjacent substituents may be joined to form a ring and a case where adjacent substituents are not joined to form a ring. When adjacent substituents can be optionally joined to form a ring, the ring formed may be monocyclic or polycyclic (including spirocyclic, endocyclic, fusedcyclic, and etc.), as well as alicyclic, heteroalicyclic, aromatic, or heteroaromatic. In such expression, adjacent substituents may refer to substituents bonded to the same atom, substituents bonded to carbon atoms which are directly bonded to each other, or substituents bonded to carbon atoms which are more distant from each other. Preferably, adjacent substituents refer to substituents bonded to the same carbon atom and substituents bonded to carbon atoms which are directly bonded to each other.

[0061] The expression that adjacent substituents can be optionally joined to form a ring is also intended to mean that two substituents bonded to the same carbon atom are joined to each other via a chemical bond to form a ring, which can be exemplified by the following formula:

##STR00011##

[0062] The expression that adjacent substituents can be optionally joined to form a ring is also intended to mean that two substituents bonded to carbon atoms which are directly bonded to each other are joined to each other via a chemical bond to form a ring, which can be exemplified by the following formula:

##STR00012##

[0063] The expression that adjacent substituents can be optionally joined to form a ring is also intended to mean that two substituents bonded to further distant carbon atoms are joined to each other via a chemical bond to form a ring, which can be exemplified by the following formula:

##STR00013##

[0064] Furthermore, the expression that adjacent substituents can be optionally joined to form a ring is also intended to mean that, in the case where one of the two substituents bonded to carbon atoms which are directly bonded to each other represents hydrogen, the second substituent is bonded at a position at which the hydrogen atom is bonded, thereby forming a ring. This is exemplified by the following formula:

##STR00014##

[0065] According to an embodiment of the present disclosure, a metal complex is disclosed. The metal complex comprises a metal M and a ligand L.sub.a coordinated to the metal M, wherein the metal M is selected from metals having a relative atomic mass greater than 40, and the ligand L.sub.a has a structure represented by Formula 1:

##STR00015##

wherein [0066] Z.sub.1 and Z.sub.2 are each independently selected from C or N, and Z.sub.1 and Z.sub.2 are different; [0067] W is, at each occurrence identically or differently, selected from B, N or P; [0068] ring A, ring C, and ring D are, at each occurrence identically or differently, selected from a five-membered unsaturated carbocyclic ring, an aromatic ring having 6 to 30 carbon atoms or a heteroaromatic ring having 3 to 30 carbon atoms; [0069] ring B is selected from a hetero ring having 5 to 30 ring atoms; [0070] R.sub.a, R.sub.b, R.sub.c, and R.sub.d represent, at each occurrence identically or differently, mono-substitution, multiple substitutions or non-substitution; [0071] R.sub.a, R.sub.b, R.sub.c, and R.sub.d are, at each occurrence identically or differently, selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted arylalkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted alkynyl having 2 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a sulfanyl group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof; [0072] adjacent substituents R.sub.a, R.sub.b, R.sub.c, and R.sub.d can be optionally joined to form a ring.

[0073] In the present disclosure, the expression that adjacent substituents R.sub.a, R.sub.b, R.sub.c, and R.sub.d can be optionally joined to form a ring is intended to mean that any one or more of groups of adjacent substituents, such as adjacent substituents R.sub.a, adjacent substituents R.sub.b, adjacent substituents R.sub.c, adjacent substituents R.sub.d, adjacent substituents R.sub.a and R.sub.b, and adjacent substituents R.sub.a and R.sub.d, can be joined to form a ring. Obviously, it is also possible that none of these adjacent substituents are joined to form a ring.

[0074] According to an embodiment of the present disclosure, the metal complex optionally comprises other ligands which are optionally joined to L.sub.a to form a tridentate ligand, a tetradentate ligand, a pentadentate ligand or a hexadentate ligand.

[0075] According to an embodiment of the present disclosure, in L.sub.a, ring A, ring C, and ring D are, at each occurrence identically or differently, selected from an aromatic ring having 6 to 18 carbon atoms or a heteroaromatic ring having 3 to 18 carbon atoms; and ring B is selected from a heteroaromatic ring having 5 to 18 ring atoms.

[0076] According to an embodiment of the present disclosure, in L.sub.a, ring A, ring C, and ring D are, at each occurrence identically or differently, selected from an aromatic ring having 6 to 10 carbon atoms or a heteroaromatic ring having 3 to 10 carbon atoms; and ring B is selected from a fused heteroaromatic ring having 8 to 18 ring atoms.

[0077] In this embodiment, the expression that ring B is selected from a fused heteroaromatic ring having 8 to 18 ring atoms is intended to mean that the ring B is selected from a fused heteroaromatic ring and the fused heteroaromatic ring has 8 to 18 ring atoms. For example, when ring B is selected from an indole ring, ring B is a fused heteroaromatic ring and has 9 ring atoms. For example, when ring B is selected from an azaindole ring, ring B is a fused heteroaromatic ring and has 9 ring atoms.

[0078] According to an embodiment of the present disclosure, in L.sub.a, ring A, ring C, and ring D are each independently selected from a benzene ring, a pyridine ring, a pyrimidine ring, a furan ring, a thiophene ring, a pyrrole ring, an imidazole ring, a thiazole ring, an oxazole ring, a pyrazole ring, an isothiazole ring, an isoxazole ring, a naphthalene ring, a quinoline ring, an isoquinoline ring, a naphthyridine ring, a benzofuran ring, a benzothiophene ring, a benzimidazole ring, a benzothiazole ring, a benzoxazole ring, a pyridofuran ring or a pyridothiophene ring; and ring B is selected from a pyrrole ring, an indole ring, an imidazole ring, a pyrazole ring or an azaindole ring.

[0079] According to an embodiment of the present disclosure, in L.sub.a, ring A, ring C, and ring D are each independently selected from a benzene ring, a naphthalene ring, a pyridine ring or a pyrimidine ring; and ring B is selected from a pyrrole ring, an indole ring or an azaindole ring.

[0080] According to an embodiment of the present disclosure, L.sub.a is selected from a structure represented by any one of Formula 2 to Formula 19:

##STR00016##

##STR00017##

##STR00018##

##STR00019##

##STR00020##

##STR00021##

##STR00022##

##STR00023##

##STR00024##

##STR00025##

##STR00026##

##STR00027##

##STR00028##

##STR00029##

##STR00030##

##STR00031##

##STR00032##

##STR00033##

wherein [0081] Z.sub.1 and Z.sub.2 are each independently selected from C or N, and Z.sub.1 and Z.sub.2 are different; [0082] W is, at each occurrence identically or differently, selected from B, N or P; [0083] A.sub.1 to A.sub.4 are, at each occurrence identically or differently, selected from N or CR.sub.a; [0084] B.sub.1 to B.sub.4 are, at each occurrence identically or differently, selected from N or CR.sub.b; [0085] C.sub.1 to C.sub.5 are, at each occurrence identically or differently, selected from N or CR.sub.c; [0086] D.sub.1 to D.sub.4 are, at each occurrence identically or differently, selected from N or CR.sub.d; [0087] Z.sub.3 is, at each occurrence identically or differently, selected from O, S, Se, NR.sub.Z, CR.sub.ZR.sub.Z, SiR.sub.zR.sub.z or PR.sub.z; when two R.sub.z are present at the same time, the two R.sub.z are identical or different; [0088] R.sub.a, R.sub.b, R.sub.c, R.sub.d, and R.sub.z are, at each occurrence identically or differently, selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted arylalkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted alkynyl having 2 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a sulfanyl group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof; [0089] adjacent substituents R.sub.a, R.sub.b, R.sub.c, R.sub.d, and R.sub.z can be optionally joined to form a ring.

[0090] According to an embodiment of the present disclosure, L.sub.a is selected from a structure represented by Formula 2, Formula 4, Formula 7, Formula 10, Formula 16 or Formula 17.

[0091] According to an embodiment of the present disclosure, L.sub.a is selected from a structure represented by Formula 2, Formula 4, Formula 10 or Formula 16.

[0092] According to an embodiment of the present disclosure, in Formula 2 to Formula 19, Z.sub.1 is N, and Z.sub.2 is C.

[0093] According to an embodiment of the present disclosure, in Formula 2 to Formula 19, Z.sub.2 is N, and Z.sub.1 is C.

[0094] According to an embodiment of the present disclosure, in Formula 2 to Formula 19, W is N.

[0095] According to an embodiment of the present disclosure, in Formula 2 to Formula 19, Z.sub.1 is N, and D.sub.1 and/or D.sub.2 are N; or in Formula 2 to Formula 19, Z.sub.2 is N, and C.sub.1 and/or C.sub.2 are N.

[0096] According to an embodiment of the present disclosure, in Formula 2 to Formula 19, Z.sub.1 is N, and D.sub.2 is N; or in Formula 2 to Formula 19, Z.sub.2 is N, and C.sub.2 is N.

[0097] According to an embodiment of the present disclosure, A.sub.1 to A.sub.4 are each independently selected from CR.sub.a, B.sub.1 to B.sub.4 are each independently selected from CR.sub.b, C.sub.1 to C.sub.5 are each independently selected from CR.sub.c, and D.sub.1 to D.sub.4 are each independently selected from CR.sub.a; R.sub.a, R.sub.b, R.sub.c, and R.sub.d are, at each occurrence identically or differently, selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted arylalkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted alkynyl having 2 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a sulfanyl group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof; [0098] adjacent substituents R.sub.a, R.sub.b, R.sub.c, and R.sub.d can be optionally joined to form a ring.

[0099] According to an embodiment of the present disclosure, A.sub.1 to A.sub.4 are each independently selected from CR.sub.a, B.sub.1 to B.sub.4 are each independently selected from CR.sub.b, C.sub.1 to C.sub.5 are each independently selected from CR.sub.c, and D.sub.1 to D.sub.4 are each independently selected from CR.sub.a; R.sub.a, R.sub.b, R.sub.c, and R.sub.d are, at each occurrence identically or differently, selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, a cyano group, and combinations thereof; [0100] adjacent substituents R.sub.a, R.sub.b, R.sub.c, and R.sub.d can be optionally joined to form a ring.

[0101] According to an embodiment of the present disclosure, A.sub.1 to A.sub.4 are each independently selected from CR.sub.a, B.sub.1 to B.sub.4 are each independently selected from CR.sub.b, C.sub.1 to C.sub.5 are each independently selected from CR.sub.c, and D.sub.1 to D.sub.4 are each independently selected from CR.sub.a; R.sub.a, R.sub.b, R.sub.c, and R.sub.d are, at each occurrence identically or differently, selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, a cyano group, and combinations thereof; [0102] adjacent substituents R.sub.a, R.sub.b, R.sub.c, and R.sub.d can be optionally joined to form a ring.

[0103] According to an embodiment of the present disclosure, in Formula 2 and Formula 4 to Formula 18, at least one of A.sub.1 to A.sub.n is, at each occurrence identically or differently, selected from CR.sub.a, and A.sub.n corresponds to one having the largest serial number among A.sub.1 to A.sub.4 in Formula 2 and Formula 4 to Formula 18; or [0104] in Formula 2 to Formula 19, at least one of B.sub.1 to B.sub.n is, at each occurrence identically or differently, selected from CR.sub.b, and B.sub.n corresponds to one having the largest serial number among B.sub.1 to B.sub.4 in any one of Formula 2 to Formula 19; or [0105] in Formula 2 to Formula 19, at least one of C.sub.1 to C.sub.n is, at each occurrence identically or differently, selected from CR.sub.c, and C.sub.n corresponds to one having the largest serial number among C.sub.1 to C.sub.5 in any one of Formula 2 to Formula 19; or [0106] in Formula 2 to Formula 19, at least one of D.sub.1 to D.sub.n is, at each occurrence identically or differently, selected from CR.sub.d, and D.sub.n corresponds to one having the largest serial number among D.sub.1 to D.sub.4 in any one of Formula 2 to Formula 19; [0107] R.sub.a, R.sub.b, R.sub.c, and R.sub.d are, at each occurrence identically or differently, selected from the group consisting of: deuterium, halogen, cyano, hydroxyl, sulfanyl, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted arylalkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, and combinations thereof; [0108] adjacent substituents R.sub.a, R.sub.b, R.sub.c, and R.sub.d can be optionally joined to form a ring.

[0109] In the present disclosure, in Formula 2 and Formula 4 to Formula 18, at least one of A.sub.1 to A.sub.n is, at each occurrence identically or differently, selected from CR.sub.a, and A.sub.n corresponds to one having the largest serial number among A.sub.1 to A.sub.4 in any one of Formula 2 and Formula 4 to Formula 18. For example, for Formula 2, A.sub.n corresponds to A.sub.2 whose serial number is the largest among A.sub.1 to A.sub.4 in Formula 2, that is, in Formula 2, at least one of A.sub.1 to A.sub.2 is, at each occurrence identically or differently, selected from CR.sub.a. For another example, for Formula 4, A.sub.n corresponds to A.sub.4 whose serial number is the largest among A.sub.1 to A.sub.4 in Formula 4, that is, in Formula 4, at least one of A.sub.1 to A.sub.4 is, at each occurrence identically or differently, selected from CR.sub.a. Similarly, in Formula 2 to Formula 19, at least one of B.sub.1 to B.sub.n is, at each occurrence identically or differently, selected from CR.sub.b, and B.sub.n corresponds to one having the largest serial number among B.sub.1 to B.sub.4 in any one of Formula 2 to Formula 19. For example, for Formula 2, B.sub.n corresponds to B.sub.4 whose serial number is the largest among B.sub.1 to B.sub.4 in Formula 2, that is, in Formula 2, at least one of B.sub.1 to B.sub.4 is, at each occurrence identically or differently, selected from CR.sub.b. For another example, for Formula 18, B.sub.n corresponds to B.sub.2 whose serial number is the largest among B.sub.1 to B.sub.4 in Formula 18, that is, in Formula 18, at least one of B.sub.1 to B.sub.2 is, at each occurrence identically or differently, selected from CR.sub.b. Similarly, in Formula 2 to Formula 19, at least one of C.sub.1 to C.sub.n is, at each occurrence identically or differently, selected from CR.sub.c, and C.sub.n corresponds to one having the largest serial number among C.sub.1 to C.sub.5 in any one of Formula 2 to Formula 19. For example, for Formula 2, C.sub.n corresponds to C.sub.3 whose serial number is the largest among C.sub.1 to C.sub.5 in Formula 2, that is, in Formula 2, at least one of C.sub.1 to C.sub.3 is, at each occurrence identically or differently, selected from CR.sub.c. For another example, for Formula 11, C.sub.n corresponds to C.sub.5 whose serial number is the largest among C.sub.1 to C.sub.5 in Formula 11, that is, in Formula 11, at least one of C.sub.1 to C.sub.5 is, at each occurrence identically or differently, selected from CR.sub.c. Similarly, in Formula 2 to Formula 19, at least one of D.sub.1 to D.sub.n is, at each occurrence identically or differently, selected from CR.sub.d, and D.sub.n corresponds to one having the largest serial number among D.sub.1 to D.sub.4 in any one of Formula 2 to Formula 19. For example, for Formula 2, D.sub.n corresponds to D.sub.2 whose serial number is the largest among D.sub.1 to D.sub.4 in Formula 2, that is, in Formula 2, at least one of D.sub.1 to D.sub.2 is, at each occurrence identically or differently, selected from CR.sub.a. For another example, for Formula 7, D.sub.n corresponds to D.sub.4 whose serial number is the largest among D.sub.1 to D.sub.4 in Formula 7, that is, in Formula 7, at least one of D.sub.1 to D.sub.4 is, at each occurrence identically or differently, selected from CR.sub.a.

[0110] According to an embodiment of the present disclosure, in Formula 2 and Formula 4 to Formula 18, A.sub.1 and/or A.sub.2 are, at each occurrence identically or differently, selected from CR.sub.a; or in Formula 2 to Formula 17, at least one of B.sub.2 to B.sub.4 is, at each occurrence identically or differently, selected from CR.sub.b; in Formula 18 to Formula 19, B.sub.1 and/or B.sub.2 are selected from CR.sub.b; or in Formula 2 to Formula 19, at least one of C.sub.1 to C.sub.3 is, at each occurrence identically or differently, selected from CR.sub.c; or in Formula 2 to Formula 19, D.sub.1 and/or D.sub.2 are selected from CR.sub.a; R.sub.a, R.sub.b, R.sub.c, and R.sub.d are, at each occurrence identically or differently, selected from the group consisting of: deuterium, halogen, cyano, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, and combinations thereof.

[0111] According to an embodiment of the present disclosure, in Formula 2 and Formula 4 to Formula 18, A.sub.1 and/or A.sub.2 are, at each occurrence identically or differently, selected from CR.sub.a; or in Formula 2 to Formula 17, at least one of B.sub.2 to B.sub.4 is, at each occurrence identically or differently, selected from CR.sub.b; in Formula 18 to Formula 19, B.sub.1 and/or B.sub.2 are selected from CR.sub.b; or in Formula 2 to Formula 19, at least one of C.sub.1 to C.sub.3 is, at each occurrence identically or differently, selected from CR.sub.c; or in Formula 2 to Formula 19, D.sub.1 and/or D.sub.2 are selected from CR.sub.a; R.sub.a, R.sub.b, R.sub.c, and R.sub.d are, at each occurrence identically or differently, selected from the group consisting of: deuterium, fluorine, cyano, methyl, ethyl, isopropyl, isobutyl, tert-butyl, neopentyl, cyclopentyl, cyclopentylmethyl, cyclohexyl, norbornyl, adamantly, trimethylsilyl, triethylsilyl, trimethylgermanyl, phenyl, pyridyl, triazinyl, trifluoromethyl, methoxy, dimethylamino, deuterated methyl, deuterated ethyl, deuterated isopropyl, deuterated isobutyl, deuterated tert-butyl, deuterated cyclopentyl, deuterated cyclopentylmethyl, deuterated cyclohexyl, deuterated neopentyl, and combinations thereof.

[0112] According to an embodiment of the present invention, in Formula 18 to Formula 19, B.sub.1 or B.sub.2 is selected from CR.sub.b; R.sub.b is, at each occurrence identically or differently, selected from the group consisting of: substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, and combinations thereof.

[0113] According to an embodiment of the present disclosure, L.sub.a is, at each occurrence identically or differently, selected from the group consisting of L.sub.a1 to L.sub.a1241, wherein for the specific structures of L.sub.a1 to L.sub.a1241, reference is made to claim 9.

[0114] According to an embodiment of the present disclosure, hydrogens in the structures L.sub.a1 to L.sub.a1241 can be partially or completely substituted with deuterium.

[0115] According to an embodiment of the present disclosure, L.sub.a is, at each occurrence identically or differently, selected from the group consisting of L.sub.a1 to L.sub.a1287, wherein for the specific structures of L.sub.a1 to L.sub.a1241, reference is made to claim 9, and the structures of L.sub.a1242 to L.sub.a1287 are as follows:

##STR00034##

##STR00035##

##STR00036##

##STR00037##

##STR00038##

##STR00039##

##STR00040##

##STR00041##

##STR00042##

##STR00043##

##STR00044##

##STR00045##

##STR00046##

##STR00047##

##STR00048##

##STR00049##

##STR00050##

##STR00051##

##STR00052##

##STR00053##

##STR00054##

##STR00055##

##STR00056##

##STR00057##

##STR00058##

##STR00059##

##STR00060##

##STR00061##

##STR00062##

##STR00063##

##STR00064##

##STR00065##

##STR00066##

##STR00067##

##STR00068##

##STR00069##

##STR00070##

##STR00071##

##STR00072##

##STR00073##

##STR00074##

##STR00075##

##STR00076##

##STR00077##

##STR00078##

##STR00079##

[0116] According to an embodiment of the present disclosure, hydrogens in the structures L.sub.a1 to L.sub.a1287 can be partially or fully substituted with deuterium.

[0117] According to an embodiment of the present disclosure, the metal complex has a general formula of M(L.sub.a).sub.m(L.sub.b).sub.n(L.sub.c).sub.q; [0118] wherein the metal M is selected from Ir, Rh, Re, Os, Pt, Au or Cu; L.sub.a, L.sub.b, and L.sub.c are a first ligand, a second ligand and a third ligand coordinated to the metal M, respectively; m is selected from 1, 2 or 3, n is selected from 0, 1 or 2, q is selected from 0, 1 or 2, and m+n+q is equal to an oxidation state of the metal M; when m is equal to 2 or 3, a plurality of L.sub.a can be identical or different; when n is equal to 2, two L.sub.b can be identical or different; and when q is equal to 2, two L.sub.c can be identical or different; [0119] L.sub.a, L.sub.b, and L.sub.c can be optionally joined to form a multidentate ligand; [0120] L.sub.b and L.sub.c are, at each occurrence identically or differently, selected from the group consisting of the following structures: wherein [0121] R.sub.i, R.sub.ii and R.sub.iii represent, at each occurrence identically or differently, mono-substitution, multiple substitutions or non-substitution; [0122] X.sub.a is, at each occurrence identically or differently, selected from the group consisting of: O, S, Se, NR.sub.N1, and CR.sub.C1R.sub.C2; [0123] X.sub.b and X.sub.c are, at each occurrence identically or differently, selected from the group consisting of: O, S, Se and NR.sub.N2; [0124] R.sub.i, R.sub.ii, R.sub.iii, R.sub.N1, R.sub.N2, R.sub.C1, and R.sub.C2 are, at each occurrence identically or differently, selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted arylalkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted alkynyl having 2 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a sulfanyl group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof; [0125] adjacent substituents R.sub.i, R.sub.ii, R.sub.iii, R.sub.N1, R.sub.N2, R.sub.C1 and R.sub.C2 can be optionally joined to form a ring.

[0126] In this embodiment, the expression that adjacent substituents R.sub.i, R.sub.ii, R.sub.iii, R.sub.N1, R.sub.N2, R.sub.C1 and R.sub.C2 can be optionally joined to form a ring is intended to mean that any one or more of groups of adjacent substituents in the structures of L.sub.b and L.sub.c, such as adjacent substituents R.sub.i, adjacent substituents R.sub.ii, adjacent substituents R.sub.iii, adjacent substituents R.sub.i and R.sub.ii, adjacent substituents R.sub.ii and R.sub.iii, adjacent substituents R.sub.i and R.sub.iii, adjacent substituents R.sub.i and R.sub.N1, adjacent substituents R.sub.i and R.sub.C1, adjacent substituents R.sub.i and R.sub.C2, adjacent substituents R.sub.ii and R.sub.N1, adjacent substituents R.sub.iii and R.sub.N1, adjacent substituents R.sub.ii and R.sub.C1, adjacent substituents R.sub.ii and R.sub.C2, adjacent substituents R.sub.iii and R.sub.C1, adjacent substituents R.sub.iii and R.sub.C2, adjacent substituents R.sub.i and R.sub.N2, adjacent substituents R.sub.ii and R.sub.N2, and adjacent substituents R.sub.C1 and R.sub.C2, may be joined to form a ring. Obviously, it is also possible that none of these substituents are joined to form a ring..

[0127] In this embodiment, L.sub.a, L.sub.b, and L.sub.c can be optionally joined to form a multi-dentate ligand, for example, any two or three of L.sub.a, L.sub.b, and L.sub.c can be joined to form a tetradentate ligand or a hexadentate ligand. Obviously, it is also possible that none of L.sub.a, L.sub.b and L.sub.c are joined, so that no multidentate ligand is formed.

[0128] According to an embodiment of the present disclosure, the metal M is selected from Ir, Pt or Os.

[0129] According to an embodiment of the present disclosure, the metal M is Ir.

[0130] According to an embodiment of the present disclosure, L.sub.b is, at each occurrence identically or differently, selected from the following structure:

##STR00092##

wherein R.sub.1 to R.sub.7 are, at each occurrence identically or differently, selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted arylalkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted alkynyl having 2 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a sulfanyl group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof.

[0131] According to an embodiment of the present disclosure, L.sub.b is, at each occurrence identically or differently, selected from the following structure:

##STR00093##

wherein at least one or two of R.sub.1 to R.sub.3 is(are), at each occurrence identically or differently, selected from substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms or combinations thereof; and/or at least one or two of R.sub.4 to R.sub.6 is(are), at each occurrence identically or differently, selected from substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms or combinations thereof.

[0132] According to an embodiment of the present disclosure, L.sub.b is, at each occurrence identically or differently, selected from the following structure:

##STR00094##

wherein at least two of R.sub.1 to R.sub.3 are, at each occurrence identically or differently, selected from substituted or unsubstituted alkyl having 2 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 2 to 20 carbon atoms or combinations thereof; and/or at least two of R.sub.4 to R.sub.6 are, at each occurrence identically or differently, selected from substituted or unsubstituted alkyl having 2 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 2 to 20 carbon atoms or combinations thereof.

[0133] According to an embodiment of the present disclosure, L.sub.c is, at each occurrence identically or differently, selected from the following structure:

##STR00095##

wherein R.sub.8 to R.sub.15 are, at each occurrence identically or differently, selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclyl having 3 to 20 ring atoms, substituted or unsubstituted arylalkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a sulfanyl group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof; [0134] adjacent substituents R.sub.8 to R.sub.15 can be optionally joined to form a ring.

[0135] In this embodiment, the expression that adjacent substituents R.sub.8 to R.sub.15 can be optionally joined to form a ring is intended to mean that any one or more of groups of adjacent substituents, such as substituents R.sub.8 and R.sub.9, substituents R.sub.9 and R.sub.10, substituents R.sub.10 and R.sub.11, substituents R.sub.11 and R.sub.12, substituents R.sub.12 and R.sub.13, substituents R.sub.13 and R.sub.14, and substituents R.sub.14 and R.sub.15, can be joined to form a ring. Obviously, it is also possible that none of these substituents are joined to form a ring..

[0136] According to an embodiment of the present disclosure, L.sub.b is, at each occurrence identically or differently, selected from the group consisting of L.sub.b1 to L.sub.b322, wherein for the specific structures of L.sub.b1 to L.sub.b322, reference is made to claim 13.

[0137] According to an embodiment of the present disclosure, L.sub.c is, at each occurrence identically or differently, selected from the group consisting of L.sub.c1 to L.sub.c321, wherein for the specific structures of L.sub.c1 to L.sub.c321, reference is made to claim 13.

[0138] According to an embodiment of the present disclosure, L.sub.c is, at each occurrence identically or differently, selected from the group consisting of L.sub.c1 to L.sub.c331, wherein for the specific structures of L.sub.c1 to L.sub.c321, reference is made to claim 13, and the structures of L.sub.c322 to L.sub.c331 are as follows:

##STR00096##

##STR00097##

##STR00098##

##STR00099##

##STR00100##

##STR00101##

##STR00102##

##STR00103##

##STR00104##

##STR00105##

[0139] According to an embodiment of the present disclosure, the metal complex is an Ir complex and has a structure represented by any one of Ir(L.sub.a)(L.sub.b)(L.sub.c), Ir(L.sub.a).sub.2(L.sub.b), Ir(L.sub.a).sub.2(L.sub.c), and Ir(L.sub.a)(L.sub.c).sub.2; when the metal complex has a structure of Ir(L.sub.a)(L.sub.b)(L.sub.c), L.sub.a is selected from any one of the group consisting of L.sub.a1 to L.sub.a1241, L.sub.b is selected from any one of the group consisting of L.sub.b1 to L.sub.b322, and L.sub.c is selected from any one of the group consisting of L.sub.c1 to L.sub.c321; when the metal complex has a structure of Ir(L.sub.a).sub.2(L.sub.b), L.sub.a is, at each occurrence identically or differently, selected from any one or any two of the group consisting of L.sub.a1 to L.sub.a1241, and L.sub.b is selected from any one of the group consisting of L.sub.b1 to L.sub.b322; when the metal complex has a structure of Ir(L.sub.a).sub.2(L.sub.c), L.sub.a is, at each occurrence identically or differently, selected from any one or any two of the group consisting of L.sub.a1 to L.sub.a1241, and L.sub.c is selected from any one of the group consisting of L.sub.c1 to L.sub.c321; when the metal complex has a structure of Ir(L.sub.a)(L.sub.c).sub.2, L.sub.a is selected from any one of the group consisting of L.sub.a1 to L.sub.a1241, and L.sub.c is, at each occurrence identically or differently, selected from any one or any two of the group consisting of L.sub.c1 to L.sub.c321; optionally, hydrogens in the structure of the metal complex can be partially or completely substituted with deuterium.

[0140] According to an embodiment of the present disclosure, the metal complex is an Ir complex and has a structure represented by any one of Ir(L.sub.a)(L.sub.b)(L.sub.c), Ir(L.sub.a).sub.2(L.sub.b), Ir(L.sub.a).sub.2(L.sub.c), and Ir(L.sub.a)(L.sub.c).sub.2; when the metal complex has a structure of Ir(L.sub.a)(L.sub.b)(L.sub.c), L.sub.a is selected from any one of the group consisting of L.sub.a1 to L.sub.a1287, L.sub.b is selected from any one of the group consisting of L.sub.b1 to L.sub.b322, and L.sub.c is selected from any one of the group consisting of L.sub.c1 to L.sub.c331; when the metal complex has a structure of Ir(L.sub.a).sub.2(L.sub.b), L.sub.a is, at each occurrence identically or differently, selected from any one or any two of the group consisting of L.sub.a1 to L.sub.a1287, and L.sub.b is selected from any one of the group consisting of L.sub.b1 to L.sub.b322; when the metal complex has a structure of Ir(L.sub.a).sub.2(L.sub.c), L.sub.a is, at each occurrence identically or differently, selected from any one or any two of the group consisting of L.sub.a1 to L.sub.a1287, and L.sub.c is selected from any one of the group consisting of L.sub.c1; to L.sub.c331; when the metal complex has a structure of Ir(L.sub.a)(L.sub.c).sub.2, L.sub.a is selected from any one of the group consisting of L.sub.a1 to L.sub.a1287, and L.sub.c is, at each occurrence identically or differently, selected from any one or any two of the group consisting of L.sub.c1 to L.sub.c331; optionally, hydrogens in the structure of the metal complex can be partially or completely substituted with deuterium.

[0141] According to an embodiment of the present disclosure, the metal complex is selected from the group consisting of Compound 1 to Compound 690; [0142] wherein Compounds 1 to 538 and Compound 669 to Compound 688 have the general formula of Ir(L.sub.a).sub.2(L.sub.b), wherein two L.sub.a are identical, and L.sub.a and L.sub.b are selected from structures listed in the following table, respectively:

TABLE-US-00001 Compound No. L.sub.a L.sub.b Compound No. L.sub.a L.sub.b 1 L.sub.a29 L.sub.b31 2 L.sub.a34 L.sub.b31 3 L.sub.a29 L.sub.b88 4 L.sub.a34 L.sub.b88 5 L.sub.a29 L.sub.b122 6 L.sub.a34 L.sub.b122 7 L.sub.a29 L.sub.b126 8 L.sub.a34 L.sub.b126 9 L.sub.a29 L.sub.b135 10 L.sub.a34 L.sub.b135 11 L.sub.a42 L.sub.b31 12 L.sub.a45 L.sub.b31 13 L.sub.a42 L.sub.b88 14 L.sub.a45 L.sub.b88 15 L.sub.a42 L.sub.b122 16 L.sub.a45 L.sub.b122 17 L.sub.a42 L.sub.b126 18 L.sub.a45 L.sub.b126 19 L.sub.a42 L.sub.b135 20 L.sub.a45 L.sub.b135 21 L.sub.a104 L.sub.b31 22 L.sub.a295 L.sub.b31 23 L.sub.a104 L.sub.b88 24 L.sub.a295 L.sub.b88 25 L.sub.a104 L.sub.b122 26 L.sub.a295 L.sub.b122 27 L.sub.a104 L.sub.b126 28 L.sub.a295 L.sub.b126 29 L.sub.a104 L.sub.b135 30 L.sub.a295 L.sub.b135 31 L.sub.a364 L.sub.b31 32 L.sub.a368 L.sub.b31 33 L.sub.a364 L.sub.b88 34 L.sub.a368 L.sub.b88 35 L.sub.a364 L.sub.b122 36 L.sub.a368 L.sub.b122 37 L.sub.a364 L.sub.b126 38 L.sub.a368 L.sub.b126 39 L.sub.a364 L.sub.b135 40 L.sub.a368 L.sub.b135 41 L.sub.a372 L.sub.b31 42 L.sub.a374 L.sub.b31 43 L.sub.a372 L.sub.b88 44 L.sub.a374 L.sub.b88 45 L.sub.a372 L.sub.b122 46 L.sub.a374 L.sub.b122 47 L.sub.a372 L.sub.b126 48 L.sub.a374 L.sub.b126 49 L.sub.a372 L.sub.b135 50 L.sub.a374 L.sub.b135 51 L.sub.a418 L.sub.b31 52 L.sub.a420 L.sub.b31 53 L.sub.a418 L.sub.b88 54 L.sub.a420 L.sub.b88 55 L.sub.a418 L.sub.b122 56 L.sub.a420 L.sub.b122 57 L.sub.a418 L.sub.b126 58 L.sub.a420 L.sub.b126 59 L.sub.a418 L.sub.b135 60 L.sub.a420 L.sub.b135 61 L.sub.a418 L.sub.b89 62 L.sub.a420 L.sub.b89 63 L.sub.a418 L.sub.b122 64 L.sub.a420 L.sub.b122 65 L.sub.a418 L.sub.b139 66 L.sub.a420 L.sub.b139 67 L.sub.a422 L.sub.b31 68 L.sub.a500 L.sub.b31 69 L.sub.a422 L.sub.b88 70 L.sub.a500 L.sub.b88 71 L.sub.a422 L.sub.b122 72 L.sub.a500 L.sub.b122 73 L.sub.a422 L.sub.b126 74 L.sub.a500 L.sub.b126 75 L.sub.a422 L.sub.b135 76 L.sub.a500 L.sub.b135 77 L.sub.a422 L.sub.b89 78 L.sub.a500 L.sub.b89 79 L.sub.a422 L.sub.b122 80 L.sub.a500 L.sub.b122 81 L.sub.a422 L.sub.b139 82 L.sub.a500 L.sub.b139 83 L.sub.a502 L.sub.b31 84 L.sub.a504 L.sub.b31 85 L.sub.a502 L.sub.b88 86 L.sub.a504 L.sub.b88 87 L.sub.a502 L.sub.b122 88 L.sub.a504 L.sub.b122 89 L.sub.a502 L.sub.b126 90 L.sub.a504 L.sub.b126 91 L.sub.a502 L.sub.b135 92 L.sub.a504 L.sub.b135 93 L.sub.a502 L.sub.b89 94 L.sub.a504 L.sub.b89 95 L.sub.a502 L.sub.b122 96 L.sub.a504 L.sub.b122 97 L.sub.a502 L.sub.b139 98 L.sub.a504 L.sub.b139 99 L.sub.a505 L.sub.b31 100 L.sub.a516 L.sub.b31 101 L.sub.a505 L.sub.b88 102 L.sub.a516 L.sub.b88 103 L.sub.a505 L.sub.b122 104 L.sub.a516 L.sub.b122 105 L.sub.a505 L.sub.b126 106 L.sub.a516 L.sub.b126 107 L.sub.a505 L.sub.b135 108 L.sub.a516 L.sub.b135 109 L.sub.a505 L.sub.b89 110 L.sub.a516 L.sub.b89 111 L.sub.a505 L.sub.b122 112 L.sub.a516 L.sub.b122 113 L.sub.a505 L.sub.b139 114 L.sub.a516 L.sub.b139 115 L.sub.a520 L.sub.b31 116 L.sub.a530 L.sub.b31 117 L.sub.a520 L.sub.b88 118 L.sub.a530 L.sub.b88 119 L.sub.a520 L.sub.b122 120 L.sub.a530 L.sub.b122 121 L.sub.a520 L.sub.b126 122 L.sub.a530 L.sub.b126 123 L.sub.a520 L.sub.b135 124 L.sub.a530 L.sub.b135 125 L.sub.a520 L.sub.b89 126 L.sub.a530 L.sub.b89 127 L.sub.a520 L.sub.b122 128 L.sub.a530 L.sub.b122 129 L.sub.a520 L.sub.b139 130 L.sub.a530 L.sub.b139 131 L.sub.a534 L.sub.b31 132 L.sub.a575 L.sub.b31 133 L.sub.a534 L.sub.b88 134 L.sub.a575 L.sub.b88 135 L.sub.a534 L.sub.b122 136 L.sub.a575 L.sub.b122 137 L.sub.a534 L.sub.b126 138 L.sub.a575 L.sub.b126 139 L.sub.a534 L.sub.b135 140 L.sub.a575 L.sub.b135 141 L.sub.a534 L.sub.b89 142 L.sub.a575 L.sub.b89 143 L.sub.a534 L.sub.b122 144 L.sub.a575 L.sub.b122 145 L.sub.a534 L.sub.b139 146 L.sub.a575 L.sub.b139 147 L.sub.a579 L.sub.b31 148 L.sub.a701 L.sub.b31 149 L.sub.a579 L.sub.b88 150 L.sub.a701 L.sub.b88 151 L.sub.a579 L.sub.b122 152 L.sub.a701 L.sub.b122 153 L.sub.a579 L.sub.b126 154 L.sub.a701 L.sub.b126 155 L.sub.a579 L.sub.b135 156 L.sub.a701 L.sub.b135 157 L.sub.a579 L.sub.b89 158 L.sub.a701 L.sub.b89 159 L.sub.a579 L.sub.b122 160 L.sub.a701 L.sub.b122 161 L.sub.a579 L.sub.b139 162 L.sub.a701 L.sub.b139 163 L.sub.a713 L.sub.b31 164 L.sub.a679 L.sub.b31 165 L.sub.a713 L.sub.b88 166 L.sub.a679 L.sub.b88 167 L.sub.a713 L.sub.b122 168 L.sub.a679 L.sub.b122 169 L.sub.a713 L.sub.b126 170 L.sub.a679 L.sub.b126 171 L.sub.a713 L.sub.b135 172 L.sub.a679 L.sub.b135 173 L.sub.a713 L.sub.b89 174 L.sub.a679 L.sub.b89 175 L.sub.a713 L.sub.b122 176 L.sub.a679 L.sub.b122 177 L.sub.a713 L.sub.b139 178 L.sub.a679 L.sub.b139 179 L.sub.a690 L.sub.b31 180 L.sub.a423 L.sub.b31 181 L.sub.a690 L.sub.b88 182 L.sub.a423 L.sub.b88 183 L.sub.a690 L.sub.b122 184 L.sub.a423 L.sub.b122 185 L.sub.a690 L.sub.b126 186 L.sub.a423 L.sub.b126 187 L.sub.a690 L.sub.b135 188 L.sub.a423 L.sub.b135 189 L.sub.a690 L.sub.b89 190 L.sub.a423 L.sub.b89 191 L.sub.a690 L.sub.b122 192 L.sub.a423 L.sub.b122 193 L.sub.a690 L.sub.b139 194 L.sub.a423 L.sub.b139 195 L.sub.a425 L.sub.b31 196 L.sub.a472 L.sub.b31 197 L.sub.a425 L.sub.b88 198 L.sub.a472 L.sub.b88 199 L.sub.a425 L.sub.b122 200 L.sub.a472 L.sub.b122 201 L.sub.a425 L.sub.b126 202 L.sub.a472 L.sub.b126 203 L.sub.a425 L.sub.b135 204 L.sub.a472 L.sub.b135 205 L.sub.a425 L.sub.b89 206 L.sub.a472 L.sub.b89 207 L.sub.a425 L.sub.b122 208 L.sub.a472 L.sub.b122 209 L.sub.a425 L.sub.b139 210 L.sub.a472 L.sub.b139 211 L.sub.a506 L.sub.b31 212 L.sub.a536 L.sub.b31 213 L.sub.a506 L.sub.b88 214 L.sub.a536 L.sub.b88 215 L.sub.a506 L.sub.b122 216 L.sub.a536 L.sub.b122 217 L.sub.a506 L.sub.b126 218 L.sub.a536 L.sub.b126 219 L.sub.a506 L.sub.b135 220 L.sub.a536 L.sub.b135 221 L.sub.a506 L.sub.b89 222 L.sub.a536 L.sub.b89 223 L.sub.a506 L.sub.b122 224 L.sub.a536 L.sub.b122 225 L.sub.a506 L.sub.b139 226 L.sub.a536 L.sub.b139 227 L.sub.a559 L.sub.b31 228 L.sub.a534 L.sub.b31 229 L.sub.a559 L.sub.b88 230 L.sub.a534 L.sub.b88 231 L.sub.a559 L.sub.b122 232 L.sub.a534 L.sub.b122 233 L.sub.a559 L.sub.b126 234 L.sub.a534 L.sub.b126 235 L.sub.a559 L.sub.b135 236 L.sub.a534 L.sub.b 135 237 L.sub.a559 L.sub.b89 238 L.sub.a534 L.sub.b89 239 L.sub.a559 Lb.sub.122 240 L.sub.a534 L.sub.b122 241 L.sub.a559 L.sub.b139 242 L.sub.a534 L.sub.b139 243 L.sub.a537 L.sub.b31 244 L.sub.a587 L.sub.b31 245 L.sub.a537 L.sub.b88 246 L.sub.a587 L.sub.b88 247 L.sub.a537 L.sub.b122 248 L.sub.a587 L.sub.b122 249 L.sub.a537 L.sub.b126 250 L.sub.a587 L.sub.b126 251 L.sub.a537 L.sub.b135 252 L.sub.a587 L.sub.b135 253 L.sub.a537 L.sub.b89 254 L.sub.a587 L.sub.b89 255 L.sub.a537 L.sub.b122 256 L.sub.a587 L.sub.b122 257 L.sub.a537 L.sub.b139 258 L.sub.a587 L.sub.b139 259 L.sub.a589 L.sub.b31 260 L.sub.a543 L.sub.b31 261 L.sub.a589 L.sub.b88 262 L.sub.a543 L.sub.b88 263 L.sub.a589 Lb.sub.122 264 L.sub.a543 L.sub.b122 265 L.sub.a589 L.sub.b126 266 L.sub.a543 L.sub.b126 267 L.sub.a589 L.sub.b135 268 L.sub.a543 L.sub.b135 269 L.sub.a589 L.sub.b89 270 L.sub.a543 L.sub.b89 271 L.sub.a589 L.sub.b122 272 L.sub.a543 L.sub.b122 273 L.sub.a589 L.sub.b139 274 L.sub.a543 L.sub.b139 275 L.sub.a592 L.sub.b31 276 L.sub.a622 L.sub.b31 277 L.sub.a592 L.sub.b88 278 L.sub.a622 L.sub.b88 279 L.sub.a592 L.sub.b122 280 L.sub.a622 L.sub.b122 281 L.sub.a592 L.sub.b126 282 L.sub.a622 L.sub.b126 283 L.sub.a592 L.sub.b135 284 L.sub.a622 L.sub.b135 285 L.sub.a592 L.sub.b89 286 L.sub.a622 L.sub.b89 287 L.sub.a592 L.sub.b122 288 L.sub.a622 L.sub.b122 289 L.sub.a592 L.sub.b139 290 L.sub.a622 L.sub.b139 291 L.sub.a624 L.sub.b31 292 L.sub.a635 L.sub.b31 293 L.sub.a624 L.sub.b88 294 L.sub.a635 L.sub.b88 295 L.sub.a624 L.sub.b122 296 L.sub.a635 L.sub.b122 297 L.sub.a624 L.sub.b126 298 L.sub.a635 L.sub.b126 299 L.sub.a624 L.sub.b135 300 L.sub.a635 L.sub.b135 301 L.sub.a624 L.sub.b89 302 L.sub.a635 L.sub.b89 303 L.sub.a624 L.sub.b122 304 L.sub.a635 L.sub.b122 305 L.sub.a624 L.sub.b139 306 L.sub.a635 L.sub.b139 307 L.sub.a630 L.sub.b31 308 L.sub.a654 L.sub.b31 309 L.sub.a630 L.sub.b88 310 L.sub.a654 L.sub.b88 311 L.sub.a630 L.sub.b122 312 L.sub.a654 L.sub.b122 313 L.sub.a630 L.sub.b126 314 L.sub.a654 L.sub.b126 315 L.sub.a630 L.sub.b135 316 L.sub.a654 L.sub.b135 317 L.sub.a630 L.sub.b89 318 L.sub.a654 L.sub.b89 319 L.sub.a630 L.sub.b122 320 L.sub.a654 L.sub.b122 321 L.sub.a630 L.sub.b139 322 L.sub.a654 L.sub.b139 323 L.sub.a597 L.sub.b31 324 L.sub.a701 L.sub.b31 325 L.sub.a597 L.sub.b88 326 L.sub.a701 L.sub.b88 327 L.sub.a597 L.sub.b122 328 L.sub.a701 L.sub.b122 329 L.sub.a597 L.sub.b126 330 L.sub.a701 L.sub.b126 331 L.sub.a597 L.sub.b135 332 L.sub.a701 L.sub.b135 333 L.sub.a597 L.sub.b89 334 L.sub.a701 L.sub.b89 335 L.sub.a597 L.sub.b122 336 L.sub.a701 L.sub.b122 337 L.sub.a597 L.sub.b139 338 L.sub.a701 L.sub.b139 339 L.sub.a704 L.sub.b31 340 L.sub.a706 L.sub.b31 341 L.sub.a704 L.sub.b88 342 L.sub.a706 L.sub.b88 343 L.sub.a704 L.sub.b122 344 L.sub.a706 L.sub.b122 345 L.sub.a704 L.sub.b126 346 L.sub.a706 L.sub.b126 347 L.sub.a704 L.sub.b135 348 L.sub.a706 L.sub.b135 349 L.sub.a704 L.sub.b89 350 L.sub.a706 L.sub.b89 351 L.sub.a704 L.sub.b122 352 L.sub.a706 L.sub.b122 353 L.sub.a704 L.sub.b139 354 L.sub.a706 L.sub.b139 355 L.sub.a707 L.sub.b31 356 L.sub.a713 L.sub.b31 357 L.sub.a707 L.sub.b88 358 L.sub.a713 L.sub.b88 359 L.sub.a707 L.sub.b122 360 L.sub.a713 L.sub.b122 361 L.sub.a707 L.sub.b126 362 L.sub.a713 L.sub.b126 363 L.sub.a707 L.sub.b135 364 L.sub.a713 L.sub.b135 365 L.sub.a707 L.sub.b89 366 L.sub.a713 L.sub.b89 367 L.sub.a707 L.sub.b122 368 L.sub.a713 L.sub.b122 369 L.sub.a707 L.sub.b139 370 L.sub.a713 L.sub.b139 371 L.sub.a716 L.sub.b31 372 L.sub.a720 L.sub.b31 373 L.sub.a716 L.sub.b88 374 L.sub.a720 L.sub.b88 375 L.sub.a716 L.sub.b122 376 L.sub.a720 L.sub.b122 377 L.sub.a716 L.sub.b126 378 L.sub.a720 L.sub.b126 379 L.sub.a716 L.sub.b135 380 L.sub.a720 L.sub.b135 381 L.sub.a716 L.sub.b89 382 L.sub.a720 L.sub.b89 383 L.sub.a716 L.sub.b122 384 L.sub.a720 L.sub.b122 385 L.sub.a716 L.sub.b139 386 L.sub.a720 L.sub.b139 387 L.sub.a679 L.sub.b31 388 L.sub.a682 L.sub.b31 389 L.sub.a679 L.sub.b88 390 L.sub.a682 L.sub.b88 391 L.sub.a679 L.sub.b122 392 L.sub.a682 L.sub.b122 393 L.sub.a679 L.sub.b126 394 L.sub.a682 L.sub.b126 395 L.sub.a679 L.sub.b135 396 L.sub.a682 L.sub.b135 397 L.sub.a679 L.sub.b89 398 L.sub.a682 L.sub.b89 399 L.sub.a679 L.sub.b122 400 L.sub.a682 L.sub.b122 401 L.sub.a679 L.sub.bl39 402 L.sub.a682 L.sub.b139 403 L.sub.a684 L.sub.b31 404 L.sub.a685 L.sub.b31 405 L.sub.a684 L.sub.b88 406 L.sub.a685 L.sub.b88 407 L.sub.a684 L.sub.b122 408 L.sub.a685 L.sub.b122 409 L.sub.a684 L.sub.b126 410 L.sub.a685 L.sub.b126 411 L.sub.a684 L.sub.b135 412 L.sub.a685 L.sub.b135 413 L.sub.a684 L.sub.b89 414 L.sub.a685 L.sub.b89 415 L.sub.a684 L.sub.b122 416 L.sub.a685 L.sub.b122 417 L.sub.a684 L.sub.bl39 418 L.sub.a685 L.sub.b139 419 L.sub.a690 L.sub.b31 420 L.sub.a692 L.sub.b31 421 L.sub.a690 L.sub.b88 422 L.sub.a692 L.sub.b88 423 L.sub.a690 L.sub.b122 424 L.sub.a692 L.sub.b122 425 L.sub.a690 L.sub.b126 426 L.sub.a692 L.sub.b126 427 L.sub.a690 L.sub.b135 428 L.sub.a692 L.sub.b135 429 L.sub.a690 L.sub.b89 430 L.sub.a692 L.sub.b89 431 L.sub.a690 L.sub.b122 432 L.sub.a692 L.sub.b122 433 L.sub.a690 L.sub.b139 434 L.sub.a692 L.sub.b139 435 L.sub.a695 L.sub.b31 436 L.sub.a697 L.sub.b31 437 L.sub.a695 L.sub.b88 438 L.sub.a697 L.sub.b88 439 L.sub.a695 L.sub.b122 440 L.sub.a697 L.sub.b122 441 L.sub.a695 L.sub.b126 442 L.sub.a697 L.sub.b126 443 L.sub.a695 L.sub.b135 444 L.sub.a697 L.sub.b135 445 L.sub.a695 L.sub.b89 446 L.sub.a697 L.sub.b89 447 L.sub.a695 L.sub.b122 448 L.sub.a697 L.sub.b122 449 L.sub.a695 L.sub.b139 450 L.sub.a697 L.sub.b139 451 L.sub.a698 L.sub.b31 452 L.sub.a733 L.sub.b31 453 L.sub.a695 L.sub.b88 454 L.sub.a733 L.sub.b88 455 L.sub.a698 L.sub.b122 456 L.sub.a733 L.sub.b122 457 L.sub.a698 L.sub.b126 458 L.sub.a733 L.sub.b126 459 L.sub.a698 L.sub.b135 460 L.sub.a733 L.sub.b135 461 L.sub.a695 L.sub.b89 462 L.sub.a733 L.sub.b89 463 L.sub.a698 L.sub.b122 464 L.sub.a733 L.sub.b122 465 L.sub.a698 L.sub.b139 466 L.sub.a733 L.sub.b139 467 L.sub.a755 L.sub.b31 468 L.sub.a777 L.sub.b31 469 L.sub.a755 L.sub.b88 470 L.sub.a777 L.sub.b88 471 L.sub.a755 L.sub.b122 472 L.sub.a777 L.sub.b122 473 L.sub.a755 L.sub.b126 474 L.sub.a777 L.sub.b126 475 L.sub.a755 L.sub.b135 476 L.sub.a777 L.sub.b135 477 L.sub.a755 L.sub.b89 478 L.sub.a777 L.sub.b89 479 L.sub.a755 L.sub.b122 480 L.sub.a777 L.sub.b122 481 L.sub.a755 L.sub.b139 482 L.sub.a777 L.sub.b139 483 L.sub.a788 L.sub.b31 484 L.sub.a780 L.sub.b31 485 L.sub.a788 L.sub.b88 486 L.sub.a780 L.sub.b88 487 L.sub.a788 L.sub.b122 488 L.sub.a780 L.sub.b122 489 L.sub.a788 L.sub.b126 490 L.sub.a780 L.sub.b126 491 L.sub.a788 L.sub.b135 492 L.sub.a780 L.sub.b135 493 L.sub.a788 L.sub.b89 494 L.sub.a780 L.sub.b89 495 L.sub.a788 L.sub.b122 496 L.sub.a780 L.sub.b122 497 L.sub.a788 L.sub.b139 498 L.sub.a780 L.sub.b139 499 L.sub.a791 L.sub.b31 500 L.sub.a793 L.sub.b31 501 L.sub.a791 L.sub.b88 502 L.sub.a793 L.sub.b88 503 L.sub.a791 L.sub.b122 504 L.sub.a793 L.sub.b122 505 L.sub.a791 L.sub.b126 506 L.sub.a793 L.sub.b126 507 L.sub.a791 L.sub.b135 508 L.sub.a793 L.sub.b135 509 L.sub.a791 L.sub.b89 510 L.sub.a793 L.sub.b89 511 L.sub.a791 L.sub.b122 512 L.sub.a793 L.sub.b122 513 L.sub.a791 L.sub.b139 514 L.sub.a793 L.sub.b139 515 L.sub.a794 L.sub.b31 516 L.sub.a795 L.sub.b31 517 L.sub.a794 L.sub.b88 518 L.sub.a795 L.sub.b88 519 L.sub.a794 L.sub.b122 520 L.sub.a795 L.sub.b122 521 L.sub.a794 L.sub.b126 522 L.sub.a795 L.sub.b126 523 L.sub.a794 L.sub.b135 524 L.sub.a795 L.sub.b135 525 L.sub.a794 L.sub.b89 526 L.sub.a795 L.sub.b89 527 L.sub.a794 Lb.sub.122 528 L.sub.a795 L.sub.b122 529 L.sub.a794 L.sub.b139 530 L.sub.a795 L.sub.b139 531 L.sub.a272 L.sub.b31 532 L.sub.a918 L.sub.b31 533 L.sub.a272 L.sub.b88 534 L.sub.a918 L.sub.b88 535 L.sub.a272 L.sub.b122 536 L.sub.a918 L.sub.b122 537 L.sub.a272 L.sub.b126 538 L.sub.a918 L.sub.b126 669 L.sub.a1235 L.sub.b122 670 L.sub.a1235 L.sub.b126 671 L.sub.a412 L.sub.b122 672 L.sub.a412 L.sub.b126 673 L.sub.a1247 L.sub.b31 674 L.sub.a1248 L.sub.b31 675 L.sub.a1247 L.sub.b88 676 L.sub.a1248 L.sub.b88 677 L.sub.a1247 L.sub.b122 678 L.sub.a1248 L.sub.b122 679 L.sub.a1247 L.sub.b126 680 L.sub.a1248 L.sub.b126 681 L.sub.a1249 L.sub.b31 682 L.sub.a1274 L.sub.b31 683 L.sub.a1249 L.sub.b88 684 L.sub.a1274 L.sub.b88 685 L.sub.a1249 L.sub.b122 686 L.sub.a1274 L.sub.b122 687 L.sub.a1249 L.sub.b126 688 L.sub.a1274 L.sub.b126

[0143] Compound 539 to Compound 668, Compound 689, and Compound 690 have the general formula of Ir(L.sub.a)(L.sub.c).sub.2, wherein two L.sub.c are identical, and L.sub.a and L.sub.c are selected from structures listed in the following table, respectively:

TABLE-US-00002 Compound No. L.sub.a L.sub.c Compound No. L.sub.a L.sub.c 539 L.sub.a1 L.sub.c1 540 L.sub.a1 L.sub.c3 541 L.sub.a1 L.sub.c4 542 L.sub.a1 L.sub.c11 543 L.sub.a1 L.sub.c12 544 L.sub.a1 L.sub.c13 545 L.sub.a1 L.sub.c15 546 L.sub.a1 L.sub.c16 547 L.sub.a1 L.sub.c20 548 L.sub.a1 L.sub.c21 549 L.sub.a1 L.sub.c22 550 L.sub.a1 L.sub.c23 551 L.sub.a1 L.sub.c36 552 L.sub.a1 L.sub.c37 553 L.sub.a1 L.sub.c38 554 L.sub.a1 L.sub.c39 555 L.sub.a1 L.sub.c42 556 L.sub.a1 L.sub.c43 557 L.sub.a1 L.sub.c44 558 L.sub.a1 L.sub.c47 559 L.sub.a1 L.sub.c232 560 L.sub.a1 L.sub.c233 561 L.sub.a1 L.sub.c235 562 L.sub.a1 L.sub.c251 563 L.sub.a1 L.sub.c261 564 L.sub.a1 L.sub.c271 565 L.sub.a1 L.sub.c308 566 L.sub.a1 L.sub.c309 567 L.sub.a1 L.sub.c316 568 L.sub.a1 L.sub.c319 569 L.sub.a1 L.sub.c320 570 L.sub.a1 L.sub.c321 571 L.sub.a21 L.sub.c1 572 L.sub.a21 L.sub.c3 573 L.sub.a21 L.sub.c4 574 L.sub.a21 L.sub.c11 575 L.sub.a21 L.sub.c12 576 L.sub.a21 L.sub.c13 577 L.sub.a21 L.sub.c15 578 L.sub.a21 L.sub.c16 579 L.sub.a21 L.sub.c20 580 L.sub.a21 L.sub.c21 581 L.sub.a21 L.sub.c22 582 L.sub.a21 L.sub.c23 583 L.sub.a21 L.sub.c36 584 L.sub.a21 L.sub.c37 585 L.sub.a21 L.sub.c38 586 L.sub.a21 L.sub.c39 587 L.sub.a21 L.sub.c42 588 L.sub.a21 L.sub.c43 589 L.sub.a21 L.sub.c44 590 L.sub.a21 L.sub.c47 591 L.sub.a21 L.sub.c232 592 L.sub.a21 L.sub.c233 593 L.sub.a21 L.sub.c235 594 L.sub.a21 L.sub.c251 595 L.sub.a21 L.sub.c261 596 L.sub.a21 L.sub.c271 597 L.sub.a21 L.sub.c308 598 L.sub.a21 L.sub.c309 599 L.sub.a21 L.sub.c316 600 L.sub.a21 L.sub.c319 601 L.sub.a21 L.sub.c320 602 L.sub.a21 L.sub.c321 603 L.sub.a1238 L.sub.c1 604 L.sub.a1238 L.sub.c3 605 L.sub.a1238 L.sub.c4 606 L.sub.a1238 L.sub.c11 607 L.sub.a1238 L.sub.c12 608 L.sub.a1238 L.sub.c13 609 L.sub.a1238 L.sub.c15 610 L.sub.a1238 L.sub.c16 611 L.sub.a1238 L.sub.c20 612 L.sub.a1238 L.sub.c21 613 L.sub.a1238 L.sub.c22 614 L.sub.a1238 L.sub.c23 615 L.sub.a1238 L.sub.c36 616 L.sub.a1238 L.sub.c37 617 L.sub.a1238 L.sub.c38 618 L.sub.a1238 L.sub.c39 619 L.sub.a1238 L.sub.c42 620 L.sub.a1238 L.sub.c43 621 L.sub.a1238 L.sub.c44 622 L.sub.a1238 L.sub.c47 623 L.sub.a1238 L.sub.c232 624 L.sub.a1238 L.sub.c233 625 L.sub.a1238 L.sub.c235 626 L.sub.a1238 L.sub.c251 627 L.sub.a1238 L.sub.c261 628 L.sub.a1238 L.sub.c271 629 L.sub.a1238 L.sub.c308 630 L.sub.a1238 L.sub.c309 631 L.sub.a1238 L.sub.c316 632 L.sub.a1238 L.sub.c319 633 L.sub.a1238 L.sub.c320 634 L.sub.a1238 L.sub.c321 635 L.sub.a1240 L.sub.c1 636 L.sub.a1240 L.sub.c3 637 L.sub.a1240 L.sub.c4 638 L.sub.a1240 L.sub.c11 639 L.sub.a1240 L.sub.c12 640 L.sub.a1240 L.sub.c13 641 L.sub.a1240 L.sub.c15 642 L.sub.a1240 L.sub.c16 643 L.sub.a1240 L.sub.c20 644 L.sub.a1240 L.sub.c21 645 L.sub.a1240 L.sub.c22 646 L.sub.a1240 L.sub.c23 647 L.sub.a1240 L.sub.c36 648 L.sub.a1240 L.sub.c37 649 L.sub.a1240 L.sub.c38 650 L.sub.a1240 L.sub.c39 651 L.sub.a1240 L.sub.c42 652 L.sub.a1240 L.sub.c43 653 L.sub.a1240 L.sub.c44 654 L.sub.a1240 L.sub.c47 655 L.sub.a1240 L.sub.c232 656 L.sub.a1240 L.sub.c233 657 L.sub.a1240 L.sub.c235 658 L.sub.a1240 L.sub.c251 659 L.sub.a1240 L.sub.c261 660 L.sub.a1240 L.sub.c271 661 L.sub.a1240 L.sub.c308 662 L.sub.a1240 L.sub.c309 663 L.sub.a1240 L.sub.c316 664 L.sub.a1240 L.sub.c319 665 L.sub.a1240 L.sub.c320 666 L.sub.a1240 L.sub.c321 667 L.sub.a1229 L.sub.c232 668 L.sub.a1232 L.sub.c232 689 L.sub.a1238 L.sub.c325 690 L.sub.a1287 L.sub.c232

[0144] According to an embodiment of the present disclosure, an electroluminescent device is further disclosed. The electroluminescent device comprises: [0145] an anode, [0146] a cathode, and [0147] an organic layer disposed between the anode and the cathode, wherein the organic layer comprises a metal complex whose specific structure is shown in any one of the preceding embodiments.

[0148] According to an embodiment of the present disclosure, in the device, the organic layer is a light-emitting layer, and the metal complex is a light-emitting material.

[0149] According to an embodiment of the present disclosure, the electroluminescent device emits red light.

[0150] According to an embodiment of the present disclosure, the electroluminescent device emits yellow light.

[0151] According to an embodiment of the present disclosure, the electroluminescent device emits green light.

[0152] According to an embodiment of the present disclosure, the electroluminescent device emits white light.

[0153] According to an embodiment of the present disclosure, in the device, the light-emitting layer further comprises at least one host material.

[0154] According to an embodiment of the present disclosure, in the device, the light-emitting layer further comprises at least two host materials.

[0155] According to an embodiment of the present disclosure, in the device, the at least one host material comprises at least one chemical group selected from the group consisting of: benzene, pyridine, pyrimidine, triazine, carbazole, azacarbazole, indolocarbazole, dibenzothiophene, azadibenzothiophene, dibenzofuran, azadibenzofuran, dibenzoselenophene, triphenylene, azatriphenylene, fluorene, silafluorene, naphthalene, quinoline, isoquinoline, quinazoline, quinoxaline, phenanthrene, azaphenanthrene, and combinations thereof.

[0156] According to an embodiment of the present disclosure, in the device, the host material may be a conventional host material in the related art. For example, the host material may typically comprise the following host materials without limitations:

##STR00106##

##STR00107##

##STR00108##

##STR00109##

##STR00110##

##STR00111##

##STR00112##

##STR00113##

##STR00114##

##STR00115##

##STR00116##

##STR00117##

##STR00118##

##STR00119##

##STR00120##

##STR00121##

##STR00122##

##STR00123##

##STR00124##

##STR00125##

##STR00126##

##STR00127##

##STR00128##

##STR00129##

##STR00130##

##STR00131##

##STR00132##

##STR00133##

##STR00134##

##STR00135##

##STR00136##

##STR00137##

##STR00138##

##STR00139##

##STR00140##

[0157] According to another embodiment of the present disclosure, a compound composition is further disclosed. The compound composition comprises a metal complex whose specific structure is shown in any one of the preceding embodiments.

Combination With Other Materials

[0158] The materials described in the present disclosure for a particular layer in an organic light emitting device can be used in combination with various other materials present in the device. The combinations of these materials are described in more detail in U.S. Pat. App. No. 20160359122 at paragraphs 0132-0161, which is incorporated by reference herein in its entirety. The materials described or referred to the disclosure are non-limiting examples of materials that may be useful in combination with the compounds disclosed herein, and one of skill in the art can readily consult the literature to identify other materials that may be useful in combination.

[0159] The materials described herein as useful for a particular layer in an organic light emitting device may be used in combination with a variety of other materials present in the device. For example, materials disclosed herein may be used in combination with a wide variety of dopants, transport layers, blocking layers, injection layers, electrodes and other layers that may be present. The combination of these materials is described in detail in paragraphs 0080-0101 of U.S. Pat. App. No. 20150349273, which is incorporated by reference herein in its entirety. The materials described or referred to the disclosure are non-limiting examples of materials that may be useful in combination with the compounds disclosed herein, and one of skill in the art can readily consult the literature to identify other materials that may be useful in combination.

[0160] In the embodiments of material synthesis, all reactions were performed under nitrogen protection unless otherwise stated. All reaction solvents were anhydrous and used as received from commercial sources. Synthetic products were structurally confirmed and tested for properties using one or more conventional equipment in the art (including, but not limited to, nuclear magnetic resonance instrument produced by BRUKER, liquid chromatograph produced by SHIMADZU, liquid chromatograph-mass spectrometry produced by SHIMADZU, gas chromatograph-mass spectrometry produced by SHIMADZU, differential Scanning calorimeters produced by SHIMADZU, fluorescence spectrophotometer produced by SHANGHAI LENGGUANG TECH., electrochemical workstation produced by WUHAN CORRTEST, and sublimation apparatus produced by ANHUI BEQ, etc.) by methods well known to the persons skilled in the art. In the embodiments of the device, the characteristics of the device were also tested using conventional equipment in the art (including, but not limited to, evaporator produced by ANGSTROM ENGINEERING, optical testing system produced by SUZHOU FSTAR, life testing system produced by SUZHOU FSTAR, and ellipsometer produced by BEIJING ELLITOP, etc.) by methods well known to the persons skilled in the art. As the persons skilled in the art are aware of the above-mentioned equipment use, test methods and other related contents, the inherent data of the sample can be obtained with certainty and without influence, so the above related contents are not further described in this present disclosure.

Material Synthesis Example

[0161] The method for preparing a compound in the present disclosure is not limited herein. Typically, the following compounds are used as examples without limitations, and synthesis routes and preparation methods thereof are described below.

Synthesis Example 1: Synthesis of Compound 5

[0162] Step 1: Synthesis of Intermediate 3

##STR00141##

[0163] Intermediate 1 (2.16 g, 10.9 mmol), Intermediate 2 (3.9 g, 10.9 mmol), Pd(PPh.sub.3).sub.4 (624 mg, 0.54 mmol) and Na.sub.2CO.sub.3 (1.74 g, 16.35 mmol) added to a 250 mL three-mouth flask, 1,4-dioxane/H.sub.2O (44 mL/11 mL) were added, the mixture was purged with nitrogen and reacted at 80° C. overnight. After the reaction was completed as detected by TLC, the reaction was cooled to room temperature, the reaction solution was diluted with EA and extracted by adding water. The organic phases were collected, concentrated and purified by column chromatography to give Intermediate 3 (3.94 g, with a yield of 91.9%).

[0164] Step 2: Synthesis of Intermediate 4

##STR00142##

[0165] Intermediate 3 (3.94 g, 10 mmol) and Cs.sub.2CO.sub.3 (8.1 g, 25 mmol) were mixed in DMF (100 mL), purged with nitrogen and reacted at 135° C. for 1 hour. After the reaction was completed as detected by TLC, the reaction was cooled to room temperature, and water was added to the reaction solution. The product was precipitated and filtered, and the filter cake was washed with an appropriate amount of water and PE and dried to give Intermediate 4 (2.6 g, with a yield of 72.9%).

[0166] Step 3: Synthesis of Intermediate 5

##STR00143##

[0167] Intermediate 4 (2.3 g, 6.5 mmol), Pd(OAc).sub.2 (72 mg, 0.32 mmol), tricyclohexylphosphonium tetrafluoroborate (PCy.sub.3•HBF.sub.4, 236 mg, 0.64 mmol) and K.sub.2CO.sub.3 (1.8 g, 13 mmol) were mixed in DMAc (32 mL), purged with nitrogen and reacted at 135° C. for 24 hours. The reaction was cooled to room temperature, water was added to the reaction solution, and the reaction solution was extracted with dichloromethane, concentrated and separated by column chromatography to give Intermediate 5 (720 mg, with a yield of 34.6%).

[0168] Step 4: Synthesis of Iridium dimer 6

##STR00144##

[0169] Intermediate 5 (720 mg, 2.2 mmol) and IrCl.sub.3•3H.sub.2O (282 mg, 0.8 mmol) were mixed in ethoxyethanol (12 mL) and water (4 mL), purged with nitrogen and refluxed at 130° C. for 24 hours. After the reaction was cooled to room temperature, the reaction solution was concentrated to give the crude product of Iridium dimer 6, which was directly used in the next step without further purification.

[0170] Step 5: Synthesis of Compound 5

##STR00145##

[0171] Iridium dimer 6 prepared in step 4, 3,7-diethyl-3-methyl-4,6-nonanedione (270 mg, 1.2 mmol), K.sub.2CO.sub.3 (552 mg, 4 mmol) and ethoxyethanol (12 mL) were mixed in a 100 mL single-necked flask, purged with nitrogen and reacted at 45° C. overnight. After the reaction was completed as detected by TLC, the reaction was cooled to room temperature. The reaction solution was filtered through Celite, the filter cake was washed with an appropriate amount of EtOH, and the crude product was washed with DCM and placed into a 250 mL eggplant flask. EtOH (about 10 mL) was added to the flask, and DCM was removed through rotary evaporation at room temperature. Solids were precipitated, filtered and washed with an appropriate amount of EtOH. The crude product was purified by column chromatography to give the product Compound 5 (240 mg, with a total yield of 28.4% over two steps). The product was confirmed as the target product with a molecular weight of 1056.4.

Synthesis Example 2: Synthesis of Compound 26

[0172] Step 1: Synthesis of Iridium dimer 8

##STR00146##

[0173] Intermediate 7 (45 mg, 0.13 mmol) and IrCl.sub.3•3H.sub.2O (18 mg, 0.052 mmol) were mixed in ethoxyethanol (3.9 mL) and water (1.3 mL), purged with nitrogen and refluxed at 130° C. for 24 hours. After the reaction was cooled to room temperature, the reaction solution was concentrated to give the crude product of Iridium dimer 8, which was directly used in the next step without further purification.

[0174] Step 2: Synthesis of Compound 26

##STR00147##

[0175] The prepared Iridium dimer 8, 3,7-diethyl-3-methyl-4,6-nonanedione (18 mg, 0.08 mmol), K.sub.2CO.sub.3 (36 mg, 0.26 mmol) and ethoxyethanol (4 mL) were mixed in a 100 mL single-necked flask, purged with nitrogen, and reacted at 45° C. overnight. After the reaction was completed as detected by TLC, the reaction was cooled to room temperature. The reaction solution was filtered through Celite, the filter cake was washed with an appropriate amount of EtOH, and the crude product was washed with DCM and placed into a 250 mL eggplant flask. The crude product was purified by column chromatography to give the product Compound 26 (20 mg, with a total yield of 35.0% over two steps). The product was confirmed as the target product with a molecular weight of 1100.4.

[0176] Synthesis Example 3: Synthesis of Compound 559

##STR00148##

[0177] Intermediate 9 (2.6 g, 3.2 mmol), Intermediate 10 (1.4 g, 4.8 mmol), 2-ethoxyethanol (30 mL) and DMF (30 mL) were sequentially added to a dry 250 mL round-bottom flask and heated to react at 100° C. for 120 hours under N.sub.2 protection. The filter cake was washed twice with methanol and n-hexane separately, yellow solids on the Celite were dissolved in dichloromethane. The organic phases were collected, concentrated under reduced pressure and purified by column chromatography to give Compound 559 (1.3 g, with a yield of 44.9%). The product was confirmed as the target product with a molecular weight of 904.3.

[0178] Synthesis Example 4: Synthesis of Compound 689

##STR00149##

[0179] Intermediate 11 (2.2 g, 2.3 mmol), Intermediate 12 (1.1 g, 3.2 mmol), 2-ethoxyethanol (30 mL) and DMF (30 mL) were sequentially added to a dry 250 mL round-bottom flask and heated to react at 100° C. for 120 hours under N.sub.2 protection. After the reaction was cooled, the reaction solution was filtered through Celite. The filter cake was washed twice with methanol and n-hexane separately, yellow solids on the Celite were dissolved in dichloromethane. The organic phases were collected, concentrated under reduced pressure and purified by column chromatography to give Compound 689 (0.4 g, with a yield of 16%). The product was confirmed as the target product with a molecular weight of 1072.5.

[0180] Synthesis Example 5: Synthesis of Compound 690

##STR00150##

[0181] Intermediate 9 (1.8 g, 2.2 mmol), Intermediate 13 (0.9 g, 2.6 mmol), 2-ethoxyethanol (30 mL) and DMF (30 mL) were sequentially added to a dry 250 mL round-bottom flask and heated to react at 100° C. for 120 hours under N.sub.2 protection. After the reaction was cooled, the reaction solution was filtered through Celite. The filter cake was washed twice with methanol and n-hexane separately, yellow solids on the Celite were dissolved in dichloromethane. The organic phases were collected, concentrated under reduced pressure and purified by column chromatography to give Compound 690 (0.9 g, with a yield of 43%). The product was confirmed as the target product with a molecular weight of 960.4.

Synthesis Example 6: Synthesis of Compound 35

[0182] Step 1: Synthesis of Iridium dimer 15

##STR00151##

[0183] Intermediate 14 (1.22 g, 3.42 mmol) and IrCl.sub.3•3H.sub.2O (402 mg, 1.14 mmol) were mixed in ethoxyethanol (30 mL) and water (10 mL), purged with nitrogen and refluxed at 130° C. for 24 hours. After the reaction was cooled to room temperature, the reaction solution was filtered to give Iridium dimer 15, which was directly used in the next step without further purification.

[0184] Step 2: Synthesis of Compound 35

##STR00152##

[0185] The prepared Iridium dimer 15, 3,7-diethyl-3-methyl-4,6-nonanedione (387 mg, 1.71 mmol), K.sub.2CO.sub.3 (788 mg, 5.7 mmol) and ethoxyethanol (30 mL) were mixed in a 100 mL single-necked flask, purged with nitrogen, and reacted at 60° C. overnight. After the reaction was completed as detected by TLC, the reaction was cooled to room temperature. The reaction solution was filtered through Celite, the filter cake was washed with an appropriate amount of EtOH, and the crude product was dissolved with DCM, concentrated, filtered and recrystallized from DCM/MeOH to give the product Compound 35 (360 mg, with a total yield of 28% over two steps). The product was confirmed as the target product with a molecular weight of 1128.4.

Synthesis Example 7: Synthesis of Compound 671

[0186] Step 1: Synthesis of Iridium dimer 17

##STR00153##

[0187] Intermediate 16 (74 mg, 0.18 mmol) and IrCl.sub.3•3H.sub.2O (24 mg, 0.07 mmol) were mixed in ethoxyethanol (6 mL) and water (2 mL), purged with nitrogen and refluxed at 130° C. for 24 hours. After the reaction was cooled to room temperature, the reaction solution was filtered to give the crude product of Iridium dimer 17, which was directly used in the next step without further purification.

[0188] Step 2: Synthesis of Compound 671

##STR00154##

[0189] The prepared Iridium dimer 17, 3,7-diethyl-3-methyl-4,6-nonanedione (25 mg, 0.11 mmol), K.sub.2CO.sub.3 (49 mg, 0.35 mmol) and ethoxyethanol (6 mL) were mixed in a 100 mL single-necked flask, purged with nitrogen, and reacted at 60° C. overnight. After the reaction was completed as detected by TLC, the reaction was cooled to room temperature. The reaction solution was filtered through Celite, the filter cake was washed with an appropriate amount of EtOH, the crude product was dissolved with DCM, concentrated and filtered, and the filter cake was washed with MeOH and dried to give the product Compound 671 (20 mg, with a total yield of 23% over two steps). The product was confirmed as the target product with a molecular weight of 1240.5.

[0190] Those skilled in the art will appreciate that the above preparation methods are merely exemplary. Those skilled in the art can obtain other compound structures of the present disclosure through the modifications of the preparation methods.

[0191] Through the special design of the ligand structure, the metal complex of the present disclosure can effectively regulate and control the luminescence wavelength, and the following photoluminescence (PL) spectroscopy data prove such an excellent effect of the metal complex of the present disclosure.

Spectroscopy Data

[0192] The photoluminescence (PL) spectroscopy data of the compounds of the present disclosure and a comparative compound was measured using a fluorescence spectrophotometer F98 produced by SHANGHAI LENGGUANG TECHNOLOGY CO., LTD. Samples of Compound 35 of the present disclosure and the comparative compound RD-A were prepared into solutions each with a concentration of 3×10.sup.-5 mol/L by using HPLC-grade toluene and excited at room temperature (298 K) using light with a wavelength of 500 nm, and their emission spectra were measured.

[0193] The structures of Compound 35 of the present disclosure and the comparative compound RD-A are as follows:

##STR00155##

##STR00156##

[0194] The maximum emission wavelength of the comparative compound RD-A is 575 nm in the PL spectrum, while the maximum emission wavelength of Compound 35 of the present disclosure is 625 nm in the PL spectrum and achieves the emission of red light. It can be seen that due to the special design of the ligand structure, the compounds of the present disclosure can effectively regulate and control the luminescence wavelength, which proves the excellent performance of the metal complex of the present disclosure.

[0195] In addition, the compounds of the present disclosure also have excellent device performance, and the excellent performance of the compounds of the present disclosure in the device is further verified through device examples below.

Device Example 1.1

[0196] First, a glass substrate having an indium tin oxide (ITO) anode with a thickness of 80 nm was cleaned and then treated with oxygen plasma and UV ozone. After the treatment, the substrate was dried in a glovebox to remove moisture. Then, the substrate was mounted on a substrate holder and placed in a vacuum chamber. Organic layers specified below were sequentially deposited through vacuum thermal evaporation on the ITO anode at a rate of 0.2 to 2 Angstroms per second at a vacuum degree of about 10.sup.-8 torr. Compound HI was deposited as a hole injection layer (HTL). Compound HT was deposited as a hole transport layer (HTL). Compound X-4 was deposited as an electron blocking layer (EBL). Compound 5 of the present disclosure was doped in Compound H-1 and Compound SD and co-deposited as an emissive layer (EML) (the weight ratio among Compound H-1, Compound SD and Compound 5 of the present disclosure was 80:17:3). On the EML, Compound H-1 was deposited as a hole blocking layer (HBL). On the HBL, Compound ET and 8-hydroxyquinolinolato-lithium (Liq) were co-deposited as an electron transport layer (ETL). Finally, 8-hydroxyquinolinolato-lithium (Liq) was deposited as an electron injection layer with a thickness of 1 nm, and Al was deposited as a cathode with a thickness of 120 nm. The device was transferred back to the glovebox and encapsulated with a glass lid and a moisture getter to complete the device.

Device Example 1.2

[0197] The preparation method in Device Example 1.2 was the same as that in Device Example 1.1, except that Compound H-1 and Compound SD were replaced with Compound X-4 and Compound H-12 in the emissive layer (EML) and the weight ratio among Compound X-4, Compound H-12 and Compound 5 of the present disclosure was adjusted to 47:47:6.

Device Comparative Example 1.1

[0198] The preparation method in Device Comparative Example 1.1 was the same as that in Device Example 1.1, except that Compound 5 of the present disclosure was replaced with Compound RD-A in the emissive layer (EML).

Device Comparative Example 1.2

[0199] The preparation method in Device Comparative Example 1.2 was the same as that in Device Example 1.2, except that Compound 5 of the present disclosure was replaced with Compound RD-A in the emissive layer (EML).

[0200] The structures and thicknesses of partial layers of the devices are shown in the following table. A layer using more than one material is obtained by doping different compounds at their weight ratio as recorded.

TABLE-US-00003 Part of device structures in Device Examples and Device Comparative Examples Device No. HIL HTL EBL EML HBL ETL Example 1.1 Compound HI (100 Å) Compound HT (350 Å) Compound X-4 (50 Å) Compound H-1:Compound SD:Compound 5 (80:17:3) (400 Å) Compound H-1 (50 Å) Compound ET:Liq (40:60) (350 Å) Example 1.2 Compound HI (100 Å) Compound HT (350 Å) Compound X-4 (50 Å) Compound X-4: Compound H-12:Compound 5 (47:47:6) (400 Å) Compound H-1 (50 Å) Compound ET:Liq (40:60) (350 Å) Comparative Example 1.1 Compound HI (100 Å) Compound HT (350 Å) Compound X-4 (50 Å) Compound H-1:Compound SD:Compound RD-A (80:17:3) (400 Å) Compound H-1 (50 Å) Compound ET:Liq (40:60) (350 Å) Comparative Example 1.2 Compound HI (100 Å) Compound HT (350 Å) Compound X-4 (50 Å) Compound X-4: Compound H-12:Compound RD-A (47:47:6) (400 Å) Compound H-1 (50 Å) Compound ET:Liq (40:60) (350 Å)

[0201] The structures of the materials used in the devices are shown as follows:

##STR00157##

##STR00158##

##STR00159##

##STR00160##

##STR00161##

##STR00162##

##STR00163##

##STR00164##

##STR00165##

##STR00166##

[0202] IVL characteristics of the devices were measured. The CIE data, maximum emission wavelength (λ.sub.max), voltage (V), current efficiency (CE), power efficiency (PE) and external quantum efficiency (EQE) of each device were measured at 1000 cd/m.sup.2. These data were recorded and shown in Table 2.

TABLE-US-00004 Device data Device No. CIE (x, y) λ.sub.max (nm) Voltage (V) CE (cd/A) PE (lm/W) EQE (%) Example 1.1 (0.505, 0.493) 563 2.73 79 91 25.04 Comparative Example 1.1 (0.561, 0.438) 577 2.90 58 63 23.65 Example 1.2 (0.498, 0.500) 563 2.95 92 97 27.99 Comparative Example 1.2 (0.566, 0.434) 577 3.35 56 52 23.28

Discussion

[0203] As can be seen from Table 2, compared with the device performance of the comparative compounds, the compounds of the present disclosure comprising a ligand containing multiple fused rings had significant advantages in the drive voltage and the efficiency and, moreover, had more excellent device performance in a variety of light-emitting bodies: compared with Comparative Example 1.1, the CE, PE and EQE of Example 1.1 were significantly increased by 36%, 44% and 6%, respectively, and the drive voltage was reduced by nearly 6% compared with Comparative Example 1.1; compared with Comparative Example 1.2, the device performance of Example 1.2 was more excellent, the CE, PE and EQE of Example 1.2 were more significantly increased by 64%, 86% and 20%, respectively, and the drive voltage of Example 1.2 was reduced by 12% compared with Comparative Example 1.2. The comparison of these data proves that the metal complexes of the present disclosure have excellent properties for comprehensively and greatly improving the device performance due to the special fused ring structure design of the L.sub.a ligand and fully embodies the excellent performance and excellent application prospect of the metal complexes of the present disclosure.

Device Example 2.1

[0204] The preparation method in Device Example 2.1 was the same as that in Device Example 1.1, except that Compound 5 of the present disclosure was replaced with Compound 559 of the present disclosure in the emissive layer (EML).

Device Example 2.2

[0205] The preparation method in Device Example 2.2 was the same as that in Device Example 1.2, except that Compound 5 of the present disclosure was replaced with Compound 559 of the present disclosure in the emissive layer (EML).

Device Example 2.3

[0206] The preparation method in Device Example 2.3 was the same as that in Device Example 1.2, except that Compound 5 of the present disclosure was replaced with Compound 689 of the present disclosure in the emissive layer (EML).

Device Example 2.4

[0207] The preparation method in Device Example 2.4 was the same as that in Device Example 1.2, except that Compound 5 of the present disclosure was replaced with Compound 690 of the present disclosure in the emissive layer (EML).

[0208] The structures and thicknesses of partial layers of the devices are shown in the following table. A layer using more than one material is obtained by doping different compounds at their weight ratio as recorded.

TABLE-US-00005 Part of device structures in Device Examples Device No. HIL HTL EBL EML HBL ETL Example 2.1 Compound HI (100 Å) Compound HT (350 Å) Compound X-4 (50 Å) Compound H-1:Compound SD:Compound 559 (80:17:3) (400 Å) Compound H-1 (50 Å) Compound ET:Liq (40:60) (350 Å) Example 2.2 Compound HI (100 Å) Compound HT (350 Å) Compound X-4 (50 Å) Compound X-4:Compound H-12:Compound 559 (47:47:6) (400 Å) Compound H-1 (50 Å) Compound ET:Liq (40:60) (350 Å) Example 2.3 Compound HI (100 Å) Compound HT (350 Å) Compound X-4 (50 Å) Compound X-4:Compound H-12:Compound 689 (47:47:6) (400 Å) Compound H-1 (50 Å) Compound ET:Liq (40:60) (350 Å) Example 2.4 Compound HI (100 Å) Compound HT (350 Å) Compound X-4 (50 Å) Compound X-4:Compound H-12:Compound 690 (47:47:6) (400 Å) Compound H-1 (50 Å) Compound ET:Liq (40:60) (350 Å)

[0209] The structures of the new materials used in the devices are shown as follows:

##STR00167##

##STR00168##

##STR00169##

[0210] IVL characteristics of the devices were measured. The CIE data, maximum emission wavelength (λ.sub.max), voltage (V), current efficiency (CE), power efficiency (PE) and external quantum efficiency (EQE) of each device were measured at 1000 cd/m.sup.2. These data were recorded and shown in Table 4.

TABLE-US-00006 Device data Device No. CIE (x, y) λ.sub.max Voltage CE (cd/A) PE EQE (%) (nm) (V) (lm/W) Example 2.1 (0.497, 0.499) 563 2.74 64 74 21.25 Example 2.2 (0.490, 0.507) 559 2.72 77 89 24.03 Example 2.3 (0.489, 0.508) 561 3.47 76 69 23.71 Example 2.4 (0.487, 0.510) 559 2.78 75 84 23.12

Discussion

[0211] As can be seen from the device data of Example 2.1, Example 2.2, Example 2.3 and Example 2.4, since different types of auxiliary ligands were used in the compounds of the present disclosure, the compounds of the present disclosure can successfully adjust the luminescence wavelength of the device to be in the yellow to green luminescence regions and, meanwhile, also had good device performance: the EQE of Example 2.1, Example 2.2, Example 2.3 and Example 2.4 can reach 21.25%, 24.03%, 23.71% and 23.12%, respectively, the devices obtained a high device efficiency, and Examples 2.1 to 2.4 all obtained a low voltage, especially the drive voltages of Example 2.1, Example 2.2 and Example 2.4 were very low (less than or equal to 2.78 V). More importantly, at the current density of 80 mA/cm.sup.2, the lifetime (LT97) of Example 2.1, Example 2.2 and Example 2.4 reached the long lifetime level of 112.5 hours, 257 hours and 154 hours, respectively, indicating that the metal complexes of the present disclosure are yellow and green light-emitting materials with excellent performance.

[0212] In conclusion, due to the special fused ring structure design of the La ligand, the metal complex of the present disclosure has the excellent device performance which is comprehensively improved, and moreover, the metal complex of the present disclosure can effectively control the luminescence wavelength and can meet the requirements of various luminescence bands from green light to red light of the OLED device, fully embodying the excellent application prospect of the metal complex of the present disclosure.

[0213] It should be understood that various embodiments described herein are merely embodiments and not intended to limit the scope of the present disclosure. Therefore, it is apparent to those skilled in the art that the present disclosure as claimed may include variations of specific embodiments and preferred embodiments described herein. Many of the materials and structures described herein may be replaced with other materials and structures without departing from the spirit of the present disclosure. It should be understood that various theories as to why the present disclosure works are not intended to be limitative.