Organic electroluminscent materials and devices

Abstract

To provide compounds that are useful in OLED application and offer improved OLED properties.SOLUTION: There is provided a compound having a first ligand LA having a structure illustrated below.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure generally relates to organometallic compounds and formulations and their various uses, including use as emitters in devices such as organic light emitting diodes and related electronic devices.

Background Art

[0002] Optoelectronic devices that utilize organic materials are becoming increasingly desirable for various reasons. Many of the materials used to fabricate such devices are relatively inexpensive, so organic optoelectronic devices have the potential for cost advantages over inorganic devices. In addition, due to the inherent properties of organic materials such as flexibility, the materials can be well-suited for specific applications such as fabrication on flexible substrates. Examples of organic optoelectronic devices include organic light emitting diodes / devices (OLEDs), organic phototransistors, organic photovoltaic cells, and organic photodetectors. For OLEDs, organic materials can have performance advantages over conventional materials.

[0003] OLEDs utilize thin organic films that emit light when a voltage is applied across the device. OLEDs are becoming an increasingly interesting technology for use in applications such as displays, lighting, and backlighting.

[0004] One use of emissive molecules is in full-color displays. The industry standard for such displays requires pixels that are adapted to emit specific colors referred to as "saturated" colors. In particular, these standards require saturated red, green, and blue pixels. Alternatively, OLEDs can be designed to emit white light. Conventional liquid crystal display emission from white backlights is filtered using absorption filters to produce red, green, and blue emission. Similar techniques can be used with OLEDs. White OLEDs can be either single-layer emissive layer (EML) devices or laminated structures. Color can be measured using CIE coordinates well-known in the art.

SUMMARY OF THE INVENTION

[0005] A high vertical dipole ratio (VDR) is beneficial in plasmonic devices because its emission direction couples most efficiently to the plasmon resonance mode. To achieve the highest possible VDR, the spatial arrangement of ligand substituents that most closely approximates a disk-like shape is ideal for facilitating the preferential orientation of the transition dipole moment perpendicular to the deposition plane. The present disclosure combines this design strategy with specific emitter modifications to provide beneficial device performance aspects such as lifetime, line shape, and hole mobility.

[0006] In one aspect, the present disclosure provides a compound having a first ligand L A wherein the first ligand L A has the structure of Formula I:

CHEMICAL

[0007] In another aspect, the present disclosure provides a formulation of the compounds described herein.

[0008] In yet another aspect, the present disclosure provides an OLED having an organic layer comprising the compounds described herein.

[0009] In yet another aspect, the present disclosure provides a consumer product comprising an OLED having an organic layer comprising the compounds described herein.

Brief Description of the Drawings

[0010]

Figure 1

[0011]

Figure 2

[0012]

Figure 3

[0013]

Figure 4

[0014]

Figure 5

Modes for Carrying Out the Invention

[0015] A. Terms Unless otherwise specified, the following terms used in this specification are defined as follows.

[0016] As used herein, the term “organic” includes polymeric materials and small molecule organic materials that can be used in the manufacture of organic optoelectronic devices. “Small molecule” refers to any organic material that is not a polymer, and a “small molecule” may actually be very large. A small molecule may, in some situations, contain repeating units. For example, the use of a long-chain alkyl group as a substituent does not exclude a molecule from the “small molecule” class. A small molecule may also be incorporated into a polymer, for example, as a pendant group on a polymer backbone or as part of the backbone. A small molecule may also function as the core portion of a dendrimer consisting of a series of chemical shells constructed on the core portion. The core portion of the dendrimer may be a small molecule emitter of fluorescence or phosphorescence. A dendrimer may be a “small molecule”, and all dendrimers currently used in the field of OLEDs are considered to be small molecules.

[0017] As used herein, “top” means the farthest part from the substrate, while “bottom” means the nearest part to the substrate. When a first layer is described as being “disposed on” a second layer, the first layer is disposed farther from the substrate. Unless it is specified that the first layer is “in contact with” the second layer, there may be other layers between the first layer and the second layer. For example, the cathode may be described as being “disposed on” the anode even if there are various organic layers in between.

[0018] As used herein, “solution processable” means capable of being dissolved, dispersed or transported in any liquid medium in the form of a solution or suspension and / or capable of being deposited from the medium.

[0019] A ligand may be termed "photoactive" if it is considered to directly contribute to the photoactive properties of a luminescent material. A ligand may be termed "auxiliary" if it is considered not to contribute to the photoactive properties of a luminescent material, although an auxiliary ligand may modify the properties of a photoactive ligand.

[0020] As used herein, and as will be generally understood by one of ordinary skill in the art, a first "highest occupied molecular orbital" (HOMO) or "lowest unoccupied molecular orbital" (LUMO) energy level is "greater" or "higher" than a second HOMO or LUMO energy level if the first energy level is closer to the vacuum energy level. Since ionization potential (IP) is measured as a negative energy relative to the vacuum level, a higher HOMO energy level corresponds to an IP with a smaller absolute value (less negative IP). Similarly, a higher LUMO energy level corresponds to an electron affinity (EA) with a smaller absolute value (less negative EA). In a conventional energy level diagram with the vacuum level at the top, the LUMO energy level of a material is higher than the HOMO energy level of the same material. A "higher" HOMO or LUMO energy level appears to be closer to the top of such a diagram than a "lower" HOMO or LUMO energy level.

[0021] As used herein, and as will be generally understood by one of ordinary skill in the art, a first work function is "greater" or "higher" than a second work function if the first work function has a higher absolute value. Since work function is generally measured as a negative number relative to the vacuum level, this means that a "higher" work function is more negative. In a conventional energy level diagram with the vacuum level at the top, a "higher" work function is illustrated as being further away in the downward direction from the vacuum level. Thus, the definitions of HOMO and LUMO energy levels follow a different convention than work function.

[0022] The terms "halo", "halogen", and "halide" are used interchangeably and refer to fluorine, chlorine, bromine, and iodine.

[0023] The term "acyl" refers to a substituted carbonyl group (C(O)-R s ).

[0024] The term "ester" refers to a substituted oxycarbonyl (-O-C(O)-R s or -C(O)-O-R s ).

[0025] The term "ether" refers to an -OR s group.

[0026] The terms "sulfanyl" or "thioether" are used interchangeably and refer to an -SR s group.

[0027] The term "selenyl" refers to an -SeR s group.

[0028] The term "sulfinyl" refers to an -S(O)-R s group.

[0029] The term "sulfonyl" refers to an -SO2-R s group.

[0030] The term "phosphino" refers to a -P(R s )2 group, where each R s may be the same or different.

[0031] The term "silyl" refers to a -Si(R s )3 group, where each R s may be the same or different.

[0032] The term "germyl" refers to a -Ge(R s )3 group, where each R s may be the same or different.

[0033] The term "boryl" refers to a -B(R s )2 group or its Lewis adduct -B(R s)Refers to a 3-group, where R s may be the same or different.

[0034] In each of the above, R s can be hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, and a substituent selected from the group consisting of combinations thereof. More preferred R s is selected from the group consisting of alkyl, cycloalkyl, aryl, heteroaryl, and combinations thereof.

[0035] The term "alkyl" refers to and includes both straight-chain and branched-chain alkyl groups. Preferred alkyl groups are those having 1 to 15 carbon atoms, such as methyl, ethyl, propyl, 1-methylethyl, butyl, 1-methylpropyl, 2-methylpropyl, pentyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl, 2,2-dimethylpropyl, and the like. Further, the alkyl group may be optionally substituted.

[0036] The term "cycloalkyl" refers to and includes monocyclic, polycyclic, and spiroalkyl groups. Preferred cycloalkyl groups are those containing 3 to 12 ring carbon atoms, such as cyclopropyl, cyclopentyl, cyclohexyl, bicyclo[3.1.1]heptyl, spiro[4.5]decyl, spiro[5.5]undecyl, adamantyl, and the like. Further, the cycloalkyl group may be optionally substituted.

[0037] The terms "heteroalkyl" or "heterocycloalkyl" each refer to an alkyl group or a cycloalkyl group having at least one carbon atom replaced by a heteroatom. Optionally, at least one heteroatom is selected from O, S, N, P, B, Si, and Se, preferably O, S, or N. Further, the heteroalkyl group or the heterocycloalkyl group may be further substituted.

[0038] The term "alkenyl" refers to and includes both straight-chain and branched-chain alkene groups. An alkenyl group is essentially an alkyl group containing at least one carbon-carbon double bond in the alkyl chain. A cycloalkenyl group is essentially a cycloalkyl group containing at least one carbon-carbon double bond in the cycloalkyl ring. As used herein, the term "heteroalkenyl" refers to an alkenyl group having at least one carbon atom replaced by a heteroatom. Optionally, at least one heteroatom is selected from O, S, N, P, B, Si, and Se, preferably O, S, or N. Preferred alkenyl, cycloalkenyl, or heteroalkenyl groups contain 2 to 15 carbon atoms. Further, the alkenyl, cycloalkenyl, or heteroalkenyl group may be optionally substituted.

[0039] The term "alkynyl" refers to and includes both straight-chain and branched-chain alkyne groups. An alkynyl group is essentially an alkyl group containing at least one carbon-carbon triple bond in the alkyl chain. Preferred alkynyl groups contain 2 to 15 carbon atoms. Further, the alkynyl group may be further substituted.

[0040] The terms "aralkyl" or "arylalkyl" are used interchangeably and refer to an alkyl group substituted with an aryl group. Further, the aralkyl group may be optionally substituted.

[0041] The term "heterocyclic group" refers to and includes aromatic and non-aromatic cyclic groups containing at least one heteroatom. Optionally, said at least one heteroatom is selected from O, S, N, P, B, Si, and Se, preferably O, S, or N. Heteroaromatic cyclic groups can be used interchangeably with heteroaryl. Preferred hetero-non-aromatic cyclic groups include those containing 3 to 7 ring atoms, containing at least one heteroatom, and including cyclic amines such as morpholino, piperidino, pyrrolidino, and cyclic ethers / thioethers such as tetrahydrofuran, tetrahydropyran, and tetrahydrothiophene. Further, the heterocyclic group may optionally be substituted.

[0042] The term "aryl" refers to and includes both monocyclic aromatic hydrocarbyl groups and polycyclic aromatic ring systems. The polycycle can have two or more rings in which two adjacent rings (these rings are "fused") share two carbons, where at least one of these rings is an aromatic hydrocarbon group, and for example, the other rings can be cycloalkyl, cycloalkenyl, aryl, heterocycle, and / or heteroaryl. Preferred aryl groups include those containing 6 to 30 carbon atoms, preferably 6 to 20 carbon atoms, more preferably 6 to 12 carbon atoms. Particularly preferred are aryl groups having 6, 10, or 12 carbon atoms. Suitable aryl groups include phenyl, biphenyl, triphenyl, triphenylene, tetraphenylene, naphthalene, anthracene, phenalene, phenanthrene, fluorene, pyrene, chrysene, perylene, and azulene, preferably phenyl, biphenyl, triphenyl, triphenylene, fluorene, and naphthalene. Further, the aryl group may optionally be substituted.

[0043] The term "heteroaryl" refers to and includes both monocyclic aromatic groups and polycyclic aromatic ring systems containing at least one heteroatom. Heteroatoms include, but are not limited to, O, S, N, P, B, Si, and Se. In many instances, O, S, or N are preferred heteroatoms. The hetero monocyclic aromatic system is preferably a monocyclic ring having 5 or 6 ring atoms, and the ring can have 1 to 6 heteroatoms. The hetero polycyclic ring system can have two or more rings where two atoms are common to two adjacent rings (these rings are "fused"), and at least one of these rings is heteroaryl, for example, the other rings can be cycloalkyl, cycloalkenyl, aryl, heterocycle, and / or heteroaryl. The hetero polycyclic aromatic ring system can have 1 to 6 heteroatoms per ring of the polycyclic aromatic ring system. Preferred heteroaryl groups are those containing 3 to 30 carbon atoms, preferably 3 to 20 carbon atoms, more preferably 3 to 12 carbon atoms.Suitable heteroaryl groups include dibenzothiophene, dibenzofuran, dibenzoselenophene, furan, thiophene, benzofuran, benzothiophene, benzoselenophene, carbazole, indolocarbazole, pyridylindole, 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, phenoxazine, 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 their aza analogs are included. Further, the heteroaryl group may be optionally substituted.

[0044] Among the aryl and heteroaryl groups listed above, the groups of triphenylene, naphthalene, anthracene, dibenzothiophene, dibenzofuran, dibenzoselenophene, carbazole, indolocarbazole, imidazole, pyridine, pyrazine, pyrimidine, triazine, and benzimidazole, and their respective aza analogs are of particular interest.

[0045] As used herein, the terms alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aralkyl, heterocyclic group, aryl, and heteroaryl are each independently unsubstituted or independently substituted with one or more common substituents.

[0046] In many instances, common substituents are selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, germyl, boryl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, selenyl, sulfinyl, sulfonyl, phosphino, and combinations thereof.

[0047] In some instances, preferred common substituents are selected from the group consisting of deuterium, fluorine, alkyl, cycloalkyl, heteroalkyl, alkoxy, aryloxy, amino, silyl, germyl, boryl, alkenyl, cycloalkenyl, heteroalkenyl, aryl, heteroaryl, nitrile, isonitrile, sulfanyl, and combinations thereof.

[0048] In some instances, more preferred common substituents are selected from the group consisting of deuterium, fluorine, alkyl, cycloalkyl, alkoxy, aryloxy, amino, silyl, aryl, heteroaryl, sulfanyl, and combinations thereof.

[0049] In still other instances, most preferred common substituents are selected from the group consisting of deuterium, fluorine, alkyl, cycloalkyl, aryl, heteroaryl, and combinations thereof.

[0050] The terms "substituted" and "substitution" refer to substituents other than H attached to the relevant position (e.g., carbon or nitrogen). For example, R 1 when representing monosubstitution, one R 1 must be other than H (i.e., substituted). Similarly, R 1 when representing disubstitution, two of R 1 must be other than H. Similarly, R 1 when representing zero or unsubstituted, R 1 can be hydrogen at the available valence of the ring atom, such as in the case of a carbon atom in benzene and a nitrogen atom in pyrrole, or in the case of a ring atom with a completely filled valence (e.g., nitrogen in pyridine), it simply represents nothing. The maximum number of possible substitutions in a ring structure depends on the total number of available valences at the ring atoms.

[0051] As used herein, "their combinations" indicates that one or more members of the applied list are combined to form known or chemically stable arrangements that can be conceived by those skilled in the art from the applied list. For example, alkyl and deuterium can be combined to form a partially or fully deuterated alkyl group; halogen and alkyl can be combined to form a halogenated alkyl substituent; and halogen, alkyl, and aryl can be combined to form a halogenated arylalkyl. In one example, the term substitution includes combinations of 2 to 4 of the listed groups. In another example, the term substitution includes combinations of 2 to 3 groups. In yet another example, the term substitution includes combinations of 2 groups. Preferred combinations of substituents are those containing up to 50 atoms other than hydrogen or deuterium, or those containing up to 40 atoms other than hydrogen or deuterium, or those containing up to 30 atoms other than hydrogen or deuterium. In many examples, preferred combinations of substituents contain up to 20 atoms other than hydrogen or deuterium.

[0052] As used herein, the term "aza" in fragments described herein, such as azadibenzofuran, azadibenzothiophene, etc., means that one or more of the C-H groups in each aromatic ring can be replaced by a nitrogen atom. For example, but not by way of limitation, azatriphenylene encompasses both dibenzo[f,h]quinoxaline and dibenzo[f,h]quinoline. One of ordinary skill in the art can readily envision other nitrogen analogs of the above-described aza derivatives, and it is intended that all such analogs be encompassed by the terms described herein.

[0053] As used herein, "deuterium" refers to an isotope of hydrogen. Deuterated compounds can be readily prepared using methods known in the art. For example, U.S. Patent No. 8,557,400, International Publication No. WO2006 / 095951, and U.S. Patent Application Publication No. 2011 / 0037057, the entire contents of which are incorporated by reference, describe the preparation of organometallic complexes substituted with deuterium. Further references are made by Tetrahedron 2015, 71, 1425 - 30 (Ming Yan et al.) and Angew.Chem.Int.Ed.(Reviews) 2007, 46, 7744 - 65 (Atzrodt et al.), the entire contents of which are incorporated by reference, which describe efficient routes for deuterating methylene hydrogens in benzylamine and replacing aromatic ring hydrogens with deuterium, respectively.

[0054] It should be understood that when a molecular fragment is described as being a substituent or as being attached to another moiety, its name may be described as being the fragment (e.g., phenyl, phenylene, naphthyl, dibenzofuryl) or the entire molecule (e.g., benzene, naphthalene, dibenzofuran). As used herein, these are considered equivalent even if the manner of representation of the substituent or attached fragment is different.

[0055] In some instances, pairs of adjacent substituents may optionally be joined or fused to form a ring. Preferred rings are 5-, 6-, or 7-membered carbocyclic or heterocyclic rings, including both examples where the ring portion formed by the pair of substituents is saturated and examples where the ring portion formed by the pair of substituents is unsaturated. As used herein, "adjacent" means that two relevant substituents can be adjacent to each other on the same ring such that they can form a stable fused ring system, or can be on two adjacent rings having two closest available substitutable positions, such as the 2- and 2'-positions in biphenyl or the 1- and 8-positions in naphthalene.

[0056] B. Compounds of the Present Disclosure In one aspect, the present disclosure provides a compound having a first ligand L A wherein the first ligand L A has the structure of Formula I:

Chemical formula

[0057] As used herein, a ligand is a ligand having a higher free ligand T1 energy. The free ligand T1 energy can be determined by a calculation procedure using density functional theory (DFT) modeling. For example, the DFT calculation can be performed using the B3LYP functional in the LACVP * basis system. In the first step, the geometry of the complex is optimized while constraining the triplet spin density of each ligand. In the second step, the geometry is re-optimized without imposing constraints. The spin density must still be localized on each ligand. The ligand on which the spin density is localized in the lowest energy structure is regarded as the emitting ligand. If the energy difference from the second ligand exceeds 0.1 eV or 0.20 eV or 0.30 eV, the ligand is regarded as the primary emitting ligand.

[0058] The vertical dipole ratio (VDR) is the ratio of the ensemble average of the dipoles oriented perpendicular to the substrate surface among the dipoles in the sample (where the vertical direction to the substrate surface is the same as the normal direction). As a similar concept, the horizontal dipole ratio (HDR) is the ensemble average fraction of the dipoles oriented horizontally with respect to the substrate surface. By definition, VDR + HDR = 1. The VDR can be measured by angle dependence, polarization dependence, and photoluminescence measurement. The VDR of the light-emitting layer can be determined by comparing the measured emission pattern of the photoexcited thin film sample with the pattern modeled by calculation as a function of polarization. For example, the modeled data of p-polarized emission are shown in FIG. 3. The modeled p-polarized angle photoluminescence (PL) is plotted for emitters having different VDRs. In the modeled PL, a peak is observed in the p-polarized PL near the angle of 45 degrees, and the higher the VDR of the emitter, the larger the PL peak.

[0059] In this example used to generate FIG. 3, there is a 30 nm thick film of a material with a refractive index of 1.75, and luminescence is monitored in a semi-infinite medium with a refractive index of 1.75. Each curve is normalized to a photoluminescence intensity of 1 at an angle of 0 degrees perpendicular to the surface of the film. As the VDR of the emitter changes, the peak near 45 degrees increases significantly. When fitting the experimental data to the VDR using software, the modeled VDR changes until the difference between the modeled data and the experimental data is minimized.

[0060] Importantly, the VDR represents the average dipole orientation of the luminescent compound. Thus, if additional emitters that do not contribute to luminescence are present in the luminescent layer, the VDR measurement does not report or reflect their VDRs. Further, by including a host that interacts with the emitter, the VDR of a given emitter can be modified, resulting in measured VDRs of different layers that are different from the VDRs of the emitters in different hosts. Further, in some embodiments, an exciplex or excimer that forms a luminescent state between two adjacent molecules is desirable. These luminescent states can have a different VDR than when only one of the components of the exciplex or excimer is luminescing or when present in the sample.

[0061] In some embodiments, the OLED is a plasmonic OLED. In some embodiments, the OLED is a waveguide OLED.

[0062] In some embodiments, the compound has a VDR of 0.35 or greater. In some embodiments, the compound has a VDR of 0.4 or greater. In some embodiments, the compound has a VDR of 0.45 or greater. In some embodiments, the compound has a VDR of 0.5 or greater. In some embodiments, the compound has a VDR of 0.6 or greater. In some embodiments, the compound has a VDR of 0.7 or greater. In some embodiments, the compound has a VDR of 0.8 or greater. In some embodiments, the compound has a VDR of 0.9 or greater.

[0063] In some embodiments, each of moiety A and moiety B is independently a monocyclic ring or a polycyclic fused ring system, where each ring of the monocyclic ring or polycyclic fused ring system is independently a 5- or 6-membered carbocyclic or heterocyclic ring. In some embodiments, each of moiety A and moiety B is independently aryl or heteroaryl.

[0064] In some embodiments of the compound, L A is a luminescent ligand, one or more additional ligands are ancillary ligands, and the compound comprises at least two R w moieties each independently selected from the group consisting of halogen, CF3, CN, C=O, and OR * ; each R w is independently selected from the group consisting of deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, germyl, boryl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, selenyl, sulfinyl, sulfonyl, phosphino, and combinations thereof; and the ligand L A has at least two more R * moieties than each of at least one of the ancillary ligands.

[0065] In some embodiments, the compound comprises at least two R w moieties each independently selected from the group consisting of F, CF3, CN, C=O, and OR * .

[0066] In some embodiments, the compound has a first free vector F1 represented by a first binding vector M1 that connects any two atoms in the compound and passes within 2 Å of the metal, the length of M1 being greater than 18 Å; the compound has a second free vector F2 represented by a second binding vector M2 that connects any two atoms in the compound; and the length of M2 is greater than 18 Å; and the angle between the transition dipole moment vector and the cross product of the vectors F1 and F2 is less than 45 degrees. The transition dipole moment vector is the transition dipole moment vector on the emissive ligand.

[0067] An example of the compound is shown in FIG. 5. [Chemical formula] As defined herein, a vector defined by two points within the space in the reference frame of the compound is called a "binding vector" (e.g., M1 and M2). The position of the binding vector in the space within the reference frame of the compound is fixed at its particular position within the reference frame of the compound. In contrast, a "free vector" such as F1 or F2 has only magnitude and direction. In this case, the plane P is defined by the free vectors F1 and F2, and the metal M. Thus, the cross product of F1 and F2 will define the normal to the plane P.

[0068] In some embodiments of the compound, the second free vector F2 forms an angle greater than 45 degrees with the first free vector F1. In some embodiments, the second free vector F2 is the longest vector connecting any two atoms within the molecule and forms an angle greater than 60 degrees with the first free vector F1.

[0069] In some embodiments, the lengths of the first free vector F1 and the second free vector F2 both exceed 20 Å. In some embodiments, the lengths of the first free vector F1 and the second free vector F2 both exceed 22 Å. In some embodiments, the angle formed between the transition dipole moment vector of the compound and the cross product of the vectors F1 and F2 is less than 30 degrees.

[0070] Since the emitter aligns with the electric field vector of the resulting light wave, it emits light in a direction perpendicular to the transition dipole moment (TDM) vector. Therefore, in conventional OLEDs, it is desirable to highly align the TDM vectors of the emitters horizontally and emit light in a direction perpendicular to the substrate towards the observer. By doing so, the light output is maximized, and efficiency loss mechanisms such as light waveguide in the OLED or substrate, or plasmon coupling are minimized. Plasmon coupling has conventionally been a major limitation to OLED efficiency and has been designed in the art by placing it away from the cathode, resulting in a compromised device voltage.

[0071] In some embodiments of the compound, the angle formed between the emission TDM vector of the compound and the cross product of the vectors F1 and F2 is less than 20 degrees.

[0072] In some embodiments of the compound, the compound has a plane P defined by the free vectors F1 and F2 represented by the corresponding bound vectors M1 and M2, the plane P is parallel to M1 and M2 and passes through the metal M; and the sum of the perpendicular distance from the plane P to the atom located farthest from the plane P on one side of the plane P and the perpendicular distance from the plane P to the atom located farthest from the plane P on the opposite side of the plane P is less than 14 Å.

[0073] In some embodiments of the compound, the sum of the perpendicular distance from the plane P to the atom located farthest from the plane P on one side of the plane P and the perpendicular distance from the plane P to the atom located farthest from the plane P on the opposite side of the plane P is less than 12 Å.

[0074] In some embodiments, the sum of the perpendicular distance from plane P to the atom located farthest from plane P on one side of plane P and the perpendicular distance from plane P to the atom located farthest from plane P on the opposite side of plane P is less than 10 Å.

[0075] In some embodiments, the compound has two metal-dative bonds in a trans configuration; the compound has a first vector W1 formed between any atom in the periphery of the compound and metal M; the compound has a second vector W2 formed between any other atom in the periphery of the compound and the metal; the magnitudes of the first vector W1 and the second vector W2 are each greater than 9.5 Å; the angle between the transition dipole moment vector of the compound and the cross product of the first vector W1 and the second vector W2 is less than 45 degrees.

[0076] In some embodiments, the magnitudes of the first vector W1 and the second vector W2 are each greater than 12 Å.

[0077] In some embodiments, the magnitudes of the first vector W1 and the second vector W2 are each greater than 15 Å.

[0078] In some embodiments, the angle between the transition dipole moment vector of the compound and the cross product of the first vector W1 and the second vector W2 is less than 30 degrees. In some embodiments, the angle between the transition dipole moment vector of the compound and the cross product of the first vector W1 and the second vector W2 is less than 20 degrees.

[0079] As used herein, an atom in the periphery refers to an atom in the portion that is farthest from metal M and is not shielded by other atoms. For example, the arrangement of such a chemical structure

Chemical formula

[0080] In some embodiments, the compound is defined by first and second vectors W1 and W2 and has a plane P parallel thereto; from the plane P, the sum of the perpendicular distance from the plane P to the atom located farthest from the plane P on one side of the plane P and the perpendicular distance from the plane P to the atom located farthest from the plane P on the opposite side of the plane P is less than 14 Å.

[0081] In some embodiments, the sum of the perpendicular distance from the plane P to the atom located farthest from the plane P on one side of the plane P and the perpendicular distance from the plane P to the atom located farthest from the plane P on the opposite side of the plane P is less than 12 Å.

[0082] In some embodiments, the sum of the perpendicular distance from the plane P to the atom located farthest from the plane P on one side of the plane P and the perpendicular distance from the plane P to the atom located farthest from the plane P on the opposite side of the plane P is less than 10 Å.

[0083] The perpendicular distance from the plane P is calculated using the standard formula for the distance of a point from a plane:

Equation

[0084] where a, b, c are the components of the plane normal vector, x0, y0, z0 are the coordinates of the atom, and d is the constant of the plane equation that ensures the plane passes through the metal atom.

[0085] In some embodiments, the angle between the metal coordination bond and the transition dipole moment (TDM) vector is less than 30 degrees. In some embodiments, the angle between the metal coordination bond and the transition dipole moment (TDM) vector is less than 20 degrees. In some embodiments, the angle between the metal coordination bond and the transition dipole moment (TDM) vector is less than 10 degrees.

[0086] In some embodiments, the metal M has an atomic weight greater than 40.

[0087] In some embodiments of the compound, each R, R’, R α , R β , R A , and R B is independently hydrogen or a substituent selected from the group consisting of deuterium, fluorine, alkyl, cycloalkyl, heteroalkyl, alkoxy, aryloxy, amino, silyl, germyl, boryl, alkenyl, cycloalkenyl, heteroalkenyl, aryl, heteroaryl, nitrile, isonitrile, sulfanyl, and combinations thereof.

[0088] In some embodiments of Formula I, at least one of R A or R B is partially or fully deuterated. In some embodiments, at least one R A is partially or fully deuterated. In some embodiments, at least one R B is partially or fully deuterated. In some embodiments, at least one of R or R’ is partially or fully deuterated.

[0089] In some embodiments of Formula I, at least one of R A or R B contains a silyl group or a germyl group. In some embodiments, at least one R A contains a silyl group or a germyl group.

[0090] In some embodiments, the silyl group or germyl group has the following structure: SiMe3, SiEt3, Si( i Pr)3, Si( t Bu)3, SiPh3, Si(CD3)3,

Chemical formula

[0091] In some embodiments, the silyl group refers to a -Si(R s )3 group, where each R s may be the same or different, while the germyl group refers to a -Ge(R s )3 group, where each R s may be the same or different. In some of these embodiments, R s can be hydrogen or a substituent selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, and combinations thereof. In some embodiments, each R s is independently selected from the group consisting of alkyl, cycloalkyl, aryl, heteroaryl, and combinations thereof. In some embodiments, each R s is independently selected from methyl, ethyl, t-butyl, cyclohexyl, phenyl, 4-methylphenyl, and 3,5-dimethylphenyl.

[0092] In some embodiments of Formula I, at least one R A contains silyl. In some embodiments, at least one R A contains SiMe3 or SiPh3. In some embodiments, at least one R A contains SiMe3. In some embodiments, at least one R A contains SiPh3. In some embodiments, at least one R A is silyl.

[0093] In some embodiments of Formula I, at least one R A contains germyl. In some embodiments, at least one R A contains GeMe3 or GePh3. In some embodiments, at least one R A contains GeMe3. In some embodiments, at least one RA contains GePh3. In some embodiments, at least one R A is germyl.

[0094] In some embodiments of Formula I, at least one R B contains silyl or germyl. In some embodiments, at least one R B contains silyl. In some embodiments, at least one R B contains SiMe3 or SiPh3. In some embodiments, at least one R B contains SiMe3. In some embodiments, at least one R B contains SiPh3. In some embodiments, at least one R B is silyl.

[0095] In some embodiments of Formula I, at least one R B contains germyl. In some embodiments, at least one R B contains GeMe3 or GePh3. In some embodiments, at least one R B contains GeMe3. In some embodiments, at least one R B contains GePh3. In some embodiments, at least one R B is germyl.

[0096] In some embodiments of Formula I, at least one R A or R B is -QR 1 R 2 R 3 wherein: Q is Si or Ge; R 1 , R 2 and R 3Each of them is independently a substituent selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, germyl, boryl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, selenyl, and combinations thereof; and Any two R's 1 's, R 2 's, and R 3 's may be bonded or fused to form a ring.

[0097] In some embodiments of the compound containing at least one R A or R B that is -QR 1 R 2 R 3 each of R 1 's, R 2 's, and R 3 contains at least one C atom. In some embodiments, each of R 1 's, R 2 's, and R 3 is the same. In some embodiments, at least one of R 1 's, R 2 's, or R 3 is different from the other two of R 1 's, R 2 's, and R 3 's.

[0098] In some embodiments of the compound, at least one R A contains -QR 1 R 2 R 3 In some embodiments, at least one R A is QR 1 R 2 R 3 is.

[0099] In some embodiments of the compound, at least one R B is -QR 1 R 2 R 3 and includes. In some embodiments, at least one R B is -QR 1 R 2 R 3 is.

[0100] In some embodiments of the compound, at least one R A is -QR 1 R 2 R 3 and includes, and at least one R B is -QR 1 R 2 R 3 and includes. In some embodiments, at least one R A is -QR 1 R 2 R 3 is, and at least one R B is -QR 1 R 2 R 3 is.

[0101] In some embodiments of the compound in which at least one R A or R B is -QR 1 R 2 R 3 and includes, Q is Si. In some embodiments, Q is Ge.

[0102] In some embodiments of Formula I, at least one R A or R B includes a fluorine atom directly bonded to a fused polycyclic ring system. In some embodiments, the fused polycyclic ring system is not fused to moiety A or moiety B.

[0103] In some embodiments of Formula I, at least one R A includes a fluorine atom directly bonded to a fused polycyclic ring system.

[0104] In some embodiments of Formula I, at least one R B contains a fluorine atom directly bonded to a fused polycyclic ring system.

[0105] In some embodiments of Formula I, at least one R A or R B contains at least two fluorine atoms directly bonded to a fused polycyclic ring system. In some embodiments of Formula I, at least one R A or R B contains at least three fluorine atoms directly bonded to a fused polycyclic ring system. In some embodiments of Formula I, at least one R A or R B contains at least two fluorine atoms that are not adjacent to each other. In some embodiments of Formula I, at least one R A or R B contains at least two fluorine atoms that are adjacent to each other.

[0106] In some embodiments of Formula I, the fused polycyclic ring system is selected from the group consisting of naphthalene, quinoline, isoquinoline, quinazoline, benzofuran, aza-benzofuran, benzoxazole, aza-benzoxazole, benzothiophene, aza-benzothiophene, benzothiazole, aza-benzothiazole, benzoselenophene, aza-benzoselenophene, indene, aza-indene, indole, aza-indole, benzimidazole, benzimidazole-derived carbene, aza-benzimidazole, aza-benzimidazole-derived carbene, carbazole, aza-carbazole, dibenzofuran, aza-dibenzofuran, dibenzothiophene, aza-dibenzothiophene, quinoxaline, phthalazine, phenanthrene, aza-phenanthrene, anthracene, aza-anthracene, phenanthridine, fluorene, and aza-fluorene.

[0107] In some embodiments of the compound, the metal M is selected from the group consisting of Ir, Rh, Re, Ru, Os, Pt, Pd, Ag, Au, and Cu. In some embodiments, the metal M is Ir.

[0108] In some embodiments of the compound, the compound comprises at least two metal atoms. In some embodiments, the compound comprises exactly two metal atoms. In some embodiments of the compound, the first ligand L A is coordinated to two or more of the at least two metal atoms.

[0109] In some embodiments of the compound comprising at least two metal atoms, each of the at least two metal atoms is independently selected from the group consisting of Ir, Rh, Re, Ru, Os, Pt, Pd, Ag, Au, and Cu. In some embodiments, each of the at least two metal atoms is the same.

[0110] In some embodiments of the compound comprising at least two metal atoms, at least one of the at least two metal atoms is different from the other of the at least two metal atoms. In some embodiments, the compound is a metal coordination complex comprising at least two different metals. In some embodiments, the compound is a metal coordination complex comprising at least two atoms of the same metal. In some embodiments, the compound is a metal coordination complex comprising at least two metals in different oxidation states. In some embodiments, the compound is a metal coordination complex comprising at least two metals having the same oxidation state. In some embodiments, the compound is a metal coordination complex comprising at least two metals coordinated to the same ligand. In some embodiments, the compound is a metal coordination complex comprising a single polydentate ligand and at least two metals.

[0111] In some embodiments, the compound is a metal coordination complex comprising an M-K bond, where K is an acyclic atom and M is a metal. In some embodiments, K is an oxygen atom. In some embodiments, M is Pt or Pd. In some embodiments, the compound is a metal coordination complex comprising an M-K bond, where the M-K bond is part of a chelate ring containing 6, 7, or 8 ring atoms.

[0112] In some embodiments of the compound, the compound is chiral with at least one enantiomer or diastereomer present with an enantiomeric excess of at least 5%. In some embodiments, the compound is chiral with at least one enantiomer or diastereomer present with an enantiomeric excess of at least 10%. In some embodiments, the compound is chiral with at least one enantiomer or diastereomer present with an enantiomeric excess of at least 15%. In some embodiments, the compound is chiral with at least one enantiomer or diastereomer present with an enantiomeric excess of at least 50%, 75%, 85%, or 95%.

[0113] In some embodiments of Formula I, each of moiety A and moiety B is independently a moiety of the following cyclic moiety list: benzene, pyridine, pyrimidine, pyridazine, pyrazine, triazine, imidazole, imidazole-derived carbene, pyrazole, pyrrole, oxazole, furan, thiophene, thiazole, triazole, naphthalene, quinoline, isoquinoline, quinazoline, benzofuran, aza-benzofuran, benzoxazole, aza-benzoxazole, benzothiophene, aza-benzothiophene, benzothiazole, aza-benzothiazole, benzoselenophene, aza-benzoselenophene, indene, aza-indene, indole, aza-indole, benzimidazole, benzimidazole-derived carbene, aza-benzimidazole, aza-benzimidazole-derived carbene, carbazole, aza-carbazole, dibenzofuran, aza-dibenzofuran, dibenzothiophene, aza-dibenzothiophene, quinoxaline, phthalazine, phenanthrene, aza-phenanthrene, anthracene, aza-anthracene, phenanthridine, fluorene, and aza-fluorene, selected from the group consisting of. In some embodiments, the aza-variant contains one N on the benzo ring. In some embodiments, the aza-variant contains one N on the benzo ring and the N is bonded to metal M.

[0114] In some embodiments of Formula I, moiety A is a monocyclic ring. In some embodiments, moiety A is selected from the group consisting of benzene, pyridine, pyrimidine, pyridazine, pyrazine, triazine, imidazole, pyrazole, pyrrole, oxazole, furan, thiophene, thiazole, and triazole.

[0115] In some embodiments of Formula I, moiety A is imidazole, imidazoline, or an imidazole-derived carbene. In some embodiments, moiety A is pyridine or pyrazole. In some embodiments, moiety A is a polycyclic fused ring system.

[0116] In some embodiments of Formula I, moiety A is selected from the group consisting of naphthalene, quinoline, isoquinoline, quinazoline, benzofuran, aza-benzofuran, benzoxazole, aza-benzoxazole, benzothiophene, aza-benzothiophene, benzothiazole, aza-benzothiazole, benzoselenophene, aza-benzoselenophene, indene, aza-indene, indole, aza-indole, benzimidazole, benzimidazole-derived carbene, aza-benzimidazole, aza-benzimidazole-derived carbene, carbazole, aza-carbazole, dibenzofuran, aza-dibenzofuran, dibenzothiophene, aza-dibenzothiophene, quinoxaline, phthalazine, phenanthrene, aza-phenanthrene, anthracene, aza-anthracene, phenanthridine, fluorene, and aza-fluorene.

[0117] In some embodiments of Formula I, moiety A is quinoline, isoquinoline, indazole, benzimidazole, or a benzimidazole-derived carbene.

[0118] In some embodiments of Formula I, moiety B is a monocyclic ring. In some embodiments, moiety B is selected from the group consisting of benzene, pyridine, pyrimidine, pyridazine, pyrazine, triazine, imidazole, imidazole-derived carbene, pyrazole, pyrrole, oxazole, furan, thiophene, thiazole, and triazole. In some embodiments, moiety B is benzene. In some embodiments, moiety B is a polycyclic fused ring system.

[0119] In some embodiments of Formula I, moiety B is selected from the group consisting of naphthalene, quinoline, isoquinoline, quinazoline, benzofuran, aza-benzofuran, benzoxazole, aza-benzoxazole, benzothiophene, aza-benzothiophene, benzothiazole, aza-benzothiazole, benzoselenophene, aza-benzoselenophene, indene, aza-indene, indole, aza-indole, benzimidazole, benzimidazole-derived carbene, aza-benzimidazole, aza-benzimidazole-derived carbene, carbazole, aza-carbazole, dibenzofuran, aza-dibenzofuran, dibenzothiophene, aza-dibenzothiophene, quinoxaline, phthalazine, phenanthrene, aza-phenanthrene, anthracene, aza-anthracene, phenanthridine, fluorene, and aza-fluorene.

[0120] In some embodiments of Formula I, moiety B is dibenzofuran or naphthalene.

[0121] In some embodiments, each of moiety A and moiety B can independently be a polycyclic fused ring structure. In some embodiments, each of moiety A and moiety B can independently be a polycyclic fused ring structure comprising at least 3 fused rings. In some embodiments, the polycyclic fused ring structure has two 6-membered rings and one 5-membered ring. In some such embodiments, the 5-membered ring is fused to the ring coordinated to metal M, and the second 6-membered ring is fused to the 5-membered ring. In some embodiments, each of moiety A and moiety B can independently be selected from the group consisting of dibenzofuran, dibenzothiophene, dibenzoselenophene, and their aza variants. In some such embodiments, each of moiety A and moiety B can independently be further substituted at the ortho or meta position of the O, S, or Se atom with a substituent selected from the group consisting of deuterium, fluorine, nitrile, alkyl, cycloalkyl, aryl, heteroaryl, and combinations thereof. In some such embodiments, the aza variant contains exactly one N atom at the 6-position (ortho to O, S, or Se) and has a substituent at the 7-position (meta to O, S, or Se).

[0122] In some embodiments, each of moiety A and moiety B can independently be a polycyclic fused ring structure comprising at least 4 fused rings. In some embodiments, the polycyclic fused ring structure comprises three 6-membered rings and one 5-membered ring. In some such embodiments, the 5-membered ring is fused to the ring coordinated to metal M, the second 6-membered ring is fused to the 5-membered ring, and the third 6-membered ring is fused to the second 6-membered ring. In some such embodiments, the third 6-membered ring is further substituted with a substituent selected from the group consisting of deuterium, fluorine, nitrile, alkyl, cycloalkyl, aryl, heteroaryl, and combinations thereof.

[0123] In some embodiments, each of moiety A and moiety B can independently be a polycyclic fused ring structure comprising at least five fused rings. In some embodiments, the polycyclic fused ring structure comprises four 6-membered rings and one 5-membered ring, or three 6-membered rings and two 5-membered rings. In some embodiments comprising two 5-membered rings, the 5-membered rings are fused together. In some embodiments comprising two 5-membered rings, the 5-membered rings are separated by at least one 6-membered ring. In some embodiments having one 5-membered ring, the 5-membered ring is fused to a ring coordinated to metal M, a second 6-membered ring is fused to the 5-membered ring, a third 6-membered ring is fused to the second 6-membered ring, and a fourth 6-membered ring is fused to the third 6-membered ring.

[0124] In some embodiments, each of moiety A and moiety B can independently be an aza-version of the polycyclic fused ring described above. In some such embodiments, each of moiety A and moiety B can independently contain exactly one aza N atom. In some such embodiments, each of moiety A and moiety B contains exactly two aza N atoms, which can be present in one ring or in two different rings. In some such embodiments, the ring having an aza N atom is separated from the metal M atom by at least two other rings. In some such embodiments, the ring having an aza N atom is separated from the metal M atom by at least three other rings. In some such embodiments, each of the ortho positions of the aza N atom is substituted.

[0125] In some embodiments of the compound, Z 1 is N and Z 2 is C. In some embodiments, Z 1 is a carbene carbon and Z 2 is C.

[0126] In some embodiments of the compound, each of Z 2 to Z 4 is C. In some embodiments, at least one of Z 2 to Z 4 is N.

[0127] In some embodiments of the compound, K 1 and K 2 each are direct bonds. In some embodiments, K 1 or K 2 at least one of which is not a direct bond. In some embodiments, K 1 or K 2 exactly one of which is not a direct bond.

[0128] In some embodiments of the compound, K 1 is not a direct bond and Z 1 is C.

[0129] In some embodiments of the compound, K 2 is not a direct bond and Z 2 is C.

[0130] In some embodiments of the compound, K 1 or K 2 at least one of which is O or S. In some embodiments, K 1 or K 2 at least one of which is O. In some embodiments, K 1 or K 2 at least one of which is S.

[0131] In some embodiments of the compound, K 1 or K 2 at least one of which is selected from the group consisting of N(R α ), P(R α ), and B(R α ). In some embodiments, K 1 or K 2 at least one of which is selected from the group consisting of C(R α )(R β ) and Si(R α )(R β ).

[0132] In some embodiments of the compound, K 1is a direct bond. In some embodiments, K 1 is O or S. In some embodiments, K 1 is O. In some embodiments, K 1 is S.

[0133] In some embodiments of the compound, K 1 is selected from the group consisting of N(R α ), P(R α ), and B(R α ). In some embodiments, K 1 is selected from the group consisting of C(R α )(R β ) and Si(R α )(R β ).

[0134] In some embodiments of the compound, K 2 is a direct bond. In some embodiments, K 2 is O or S. In some embodiments, K 2 is O. In some embodiments, K 2 is S.

[0135] In some embodiments of the compound, K 2 is selected from the group consisting of N(R α ), P(R α ), and B(R α ). In some embodiments, K 2 is selected from the group consisting of C(R α )(R β ) and Si(R α )(R β ).

[0136] In some embodiments of the compound, L is a direct bond. In some embodiments, L is selected from the group consisting of O, S, and Se. In some embodiments, L is selected from the group consisting of BR, NR, and PR. In some embodiments of the compound, L is BR. In some embodiments, L is NR. In some embodiments, L is PR. R in BR, NR, and PR is aryl or heteroaryl; wherein R is R A or R B is bonded or fused to one of to form a ring that is a 5-membered ring. In some embodiments, the 5-membered ring is a pyrrole ring.

[0137] In some embodiments, L is selected from the group consisting of P(O)R, C=O, C=S, C=Se, C=NR’, C=CRR’, S=O, and SO2.

[0138] In some embodiments, L is selected from the group consisting of BRR’, CRR’, SiRR’, and GeRR’.

[0139] In some embodiments, L is CR.

[0140] In some embodiments, the compound has the structure of the following EWG1 list: F, CF3, CN, COCH3, CHO, COCF3, COOMe, COOCF3, NO2, SF3, SiF3, PF4, SF5, OCF3, SCF3, SeCF3, SOCF3, SeOCF3, SO2F, SO2CF3, SeO2CF3, OSeO2CF3, OCN, SCN, SeCN, NC, + N(R k2 )3, (R k2 )2CCN, (R k2 )2CCF3, CNC(CF3)2, BR k3 R k2, substituted or unsubstituted dibenzoborole, 1-substituted carbazole, 1,9-substituted carbazole, substituted or unsubstituted carbazole, substituted or unsubstituted pyridine, substituted or unsubstituted pyrimidine, substituted or unsubstituted pyrazine, substituted or unsubstituted pyridoxine, substituted or unsubstituted triazine, substituted or unsubstituted oxazole, substituted or unsubstituted benzoxazole, substituted or unsubstituted thiazole, substituted or unsubstituted benzothiazole, substituted or unsubstituted imidazole, substituted or unsubstituted benzimidazole, ketone, carboxylic acid, ester, nitrile, isonitrile, sulfinyl, sulfonyl, partially and fully fluorinated alkyl, partially and fully fluorinated aryl, partially and fully fluorinated heteroaryl, cyano group-containing alkyl, cyano group-containing aryl, cyano group-containing heteroaryl, isocyanate, [Chemical formula] comprises an electron-withdrawing group selected from the group consisting of, wherein each R k1 represents substitution from mono-substitution to the maximum allowable number, or no substitution; Y G is BR e , NR e , PR e , O, S, Se, C=O, S=O, SO2, CR e R f , SiR e R f , and GeR e R f is selected from the group consisting of; R k1 , R k2 , R k3 , R e , and R fEach of them is independently a substituent selected from the group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, germyl, boryl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, sulfanyl, selenyl, sulfinyl, sulfonyl, phosphino, and combinations thereof.

[0141] In some embodiments, the compound has a structure of the following EWG2 list:

Chemical formula

Chemical formula

[0142] In some embodiments, the compound has a structure of the following EWG3 list:

Chemical formula

[0143] In some embodiments, the compound has a structure of the following EWG4 list:

Chemical formula

[0144] In some embodiments, the compound comprises an electron-withdrawing group that is a π-electron deficient electron-withdrawing group. In some embodiments, the π-electron deficient electron-withdrawing group has the structure of the following Pi-EWG list: CN, COCH3, CHO, COCF3, COOMe, COOCF3, NO2, SF3, SiF3, PF4, SF5, OCF3, SCF3, SeCF3, SOCF3, SeOCF3, SO2F, SO2CF3, SeO2CF3, OSeO2CF3, OCN, SCN, SeCN, NC, + N(R k2 )3, BR k2 R k3 , a substituted or unsubstituted dibenzoborole, a 1-substituted carbazole, a 1,9-substituted carbazole, a substituted or unsubstituted carbazole, a substituted or unsubstituted pyridine, a substituted or unsubstituted pyrimidine, a substituted or unsubstituted pyrazine, a substituted or unsubstituted pyridazine, a substituted or unsubstituted triazine, a substituted or unsubstituted oxazole, a substituted or unsubstituted benzoxazole, a substituted or unsubstituted thiazole, a substituted or unsubstituted benzothiazole, a substituted or unsubstituted imidazole, a substituted or unsubstituted benzimidazole, a ketone, a carboxylic acid, an ester, a nitrile, an isonitrile, a sulfinyl, a sulfonyl, a partially and fully fluorinated aryl, a partially and fully fluorinated heteroaryl, a cyano group-containing aryl, a cyano group-containing heteroaryl, an isocyanate, [Chemical formula] (wherein the variables are the same as those defined above) and is selected from the group consisting of.

[0145] In some embodiments of the compound, at least one of R A or R B is an electron-withdrawing group from the EWG1 list defined herein or comprises the same. In some embodiments, at least one of R A or R B is an electron-withdrawing group from the EWG2 list defined herein or comprises the same. In some embodiments, RA or R B At least one of is an electron-withdrawing group from the EWG3 list defined herein or includes it. In some embodiments, R A or R B At least one of is an electron-withdrawing group from the EWG4 list defined herein or includes it. In some embodiments, R A or R B At least one of is an electron-withdrawing group from the Pi-EWG list defined herein or includes it.

[0146] In some embodiments, at least one R A is an electron-withdrawing group from the EWG1 list defined herein or includes it. In some embodiments, at least one R A is an electron-withdrawing group from the EWG2 list defined herein or includes it. In some embodiments, at least one R A is an electron-withdrawing group from the EWG3 list defined herein or includes it. In some embodiments, at least one R A is an electron-withdrawing group from the EWG4 list defined herein or includes it. In some embodiments, at least one R A is an electron-withdrawing group from the Pi-EWG list defined herein or includes it.

[0147] In some embodiments, at least one R B is an electron-withdrawing group from the EWG1 list defined herein or includes it. In some embodiments, at least one R B is an electron-withdrawing group from the EWG2 list defined herein or includes it. In some embodiments, at least one R B is an electron-withdrawing group from the EWG3 list defined herein or includes it. In some embodiments, at least one R Bis an electron-withdrawing group from the EWG4 list defined herein or includes the same. In some embodiments, at least one R B is an electron-withdrawing group from the Pi-EWG list defined herein or includes the same.

[0148] In some embodiments of the compound, at least one R in Formula I A or R B includes an electron-withdrawing group other than F. In some embodiments, at least one R A includes an electron-withdrawing group other than F.

[0149] In some embodiments of the compound, at least one R B includes an electron-withdrawing group other than F.

[0150] In some embodiments, R A and R B in total at least two of which independently include an electron-withdrawing group other than F.

[0151] In some embodiments, at least one R A is an electron-withdrawing group other than F selected from the EWG1 list defined herein or includes the same. In some embodiments, at least one R A is an electron-withdrawing group other than F selected from the EWG1 list defined herein. In some embodiments, at least one R A includes an electron-withdrawing group other than F selected from the EWG1 list defined herein.

[0152] In some embodiments, at least one R A is an electron-withdrawing group other than F selected from the EWG2 list defined herein or includes the same. In some embodiments, at least one R A is an electron-withdrawing group other than F selected from the EWG2 list defined herein. In some embodiments, at least one R Aincludes an electron-withdrawing group other than F selected from the EWG2 list defined herein.

[0153] In some embodiments, at least one R A is, or includes, an electron-withdrawing group other than F selected from the EWG3 list defined herein. In some embodiments, at least one R A is an electron-withdrawing group other than F selected from the EWG3 list defined herein. In some embodiments, at least one R A includes an electron-withdrawing group other than F selected from the EWG3 list defined herein.

[0154] In some embodiments, at least one R A is, or includes, an electron-withdrawing group other than F selected from the EWG4 list defined herein. In some embodiments, at least one R A is an electron-withdrawing group other than F selected from the EWG4 list defined herein. In some embodiments, at least one R A includes an electron-withdrawing group other than F selected from the EWG4 list defined herein.

[0155] In some embodiments, at least one R A is, or includes, an electron-withdrawing group other than F selected from the Pi-EWG list defined herein. In some embodiments, at least one R A is an electron-withdrawing group other than F selected from the Pi-EWG list defined herein. In some embodiments, at least one R A includes an electron-withdrawing group other than F selected from the Pi-EWG list defined herein.

[0156] In some embodiments, at least one R B is, or includes, an electron-withdrawing group other than F selected from the EWG1 list defined herein. In some embodiments, at least one R Bis an electron-withdrawing group other than F selected from the EWG1 list defined herein. In some embodiments, at least one R B comprises an electron-withdrawing group other than F selected from the EWG1 list defined herein.

[0157] In some embodiments, at least one R B is, or comprises, an electron-withdrawing group other than F selected from the EWG2 list defined herein. In some embodiments, at least one R B is an electron-withdrawing group other than F selected from the EWG2 list defined herein. In some embodiments, at least one R B comprises an electron-withdrawing group other than F selected from the EWG2 list defined herein.

[0158] In some embodiments, at least one R B is, or comprises, an electron-withdrawing group other than F selected from the EWG3 list defined herein. In some embodiments, at least one R B is an electron-withdrawing group other than F selected from the EWG3 list defined herein. In some embodiments, at least one R B comprises an electron-withdrawing group other than F selected from the EWG3 list defined herein.

[0159] In some embodiments, at least one R B is, or comprises, an electron-withdrawing group other than F selected from the EWG4 list defined herein. In some embodiments, at least one R B is an electron-withdrawing group other than F selected from the EWG4 list defined herein. In some embodiments, at least one R B comprises an electron-withdrawing group other than F selected from the EWG4 list defined herein.

[0160] In some embodiments, at least one R Bis an electron-withdrawing group other than F selected from the Pi-EWG list defined herein, or comprises the same. In some embodiments, at least one R B is an electron-withdrawing group other than F selected from the Pi-EWG list defined herein. In some embodiments, at least one R B comprises an electron-withdrawing group other than F selected from the Pi-EWG list defined herein.

[0161] In some embodiments of the compound, at least one R A is not hydrogen. In some embodiments, at least one R A comprises at least one C atom. In some embodiments, at least one R B is not hydrogen. In some embodiments, at least one R B comprises at least one C atom.

[0162] In some embodiments, M is Ir, Z 1 is N, Z 2 is carbon, and the ring of moiety A containing Z 1 is imidazoline. In some embodiments, M is Ir, Z 1 is N, Z 2 is carbon, Z 1 and the ring of moiety A containing it is pyridine.

[0163] In some embodiments, ligand L A has the structure of List 1 below:

Chemical formula

Chemical formula

[0164] In some embodiments of the compound, the ligand L A has the structure of List 2 below:

Chemical formula

Chem.

[0165] In some embodiments, the ligand L A is selected from L Ai wherein i is an integer from 1 to 99, and each L Ai is defined in List 3 below:

Chem.

Chem.

Chem.

Chem.

Chem.

Chem.

[0166] In some embodiments of the compound, the compound has the formula M(L A ) p (L B ) q (L C ) r , wherein L B and L C are each bidentate ligands, p is 1, 2, or 3, q is 0, 1, or 2, r is 0, 1, or 2, and p + q + r is the oxidation state of the metal M. In some embodiments, the compound has the formula selected from the group consisting of Ir(L A )3, Ir(L A )(L B )2, Ir(L A )2(L B ), Ir(L A )2(L C ), and Ir(L A )(L B )(L C ), and L A , L B , and L C are different from each other. In some embodiments, L B is a substituted or unsubstituted phenylpyridine, and L C is a substituted or unsubstituted acetylacetonate.

[0167] In some embodiments of the compound, the compound has the formula M(L A ) p (L B ) q (L C ) r , where L B and L C are each independently selected from the following list of structures of List 4:

Chemical formula

Chemical formula

[0168] In some embodiments, at least one R a1 、R b1 、R c1 、R d1 、R a 、R b 、R c 、R d 、R e 、or R f in the structure provided in List 4 contains silyl or germyl. In some embodiments, at least one R a1 、R b1 、R c1 、R d1 、R a 、R b 、R c 、R d 、R e 、or R f in the structure provided in List 4 contains silyl. In some embodiments, at least one R a1 、R b1 、R c1 、R d1 、R a 、R b 、R c 、R d 、Re or R f contains germyl.

[0169] In some embodiments of the compound, the compound is M(L A ) p (L B ) q (L C ) r having the formula of, where L B and L C are each independently a structure of List 5 below:

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

[0170] M(L A ) p (L B ) q (L C ) r In some embodiments of the compounds having the formula, L A is selected from L Ai , where i is an integer from 1 to 98; and L B can be selected from L Bk , where k is an integer from 1 to 836, When the compound has the formula Ir(L Ai )3, the compound is selected from the group consisting of Ir(L A1 )3 to Ir(L A98 )3; When the compound has the formula Ir(L Ai )(L Bk )2, the compound is selected from the group consisting of Ir(L A1 )(L B1 )2 to Ir(L A98 )(L B836 )2; When the compound has the formula Ir(L Ai )2(L Bk ), the compound is Ir(L A1 )2(L B1 ) to Ir(L A98 )2(LB836 selected from the group consisting of; When the compound has the formula Ir(L Ai )2(L Cj-I ), the compound is selected from the group consisting of Ir(L A1 )2(L C1-I ) to Ir(L A98 )2(L C1416-I ); and When the compound has the formula Ir(L Ai )2(L Cj-II ), the compound is selected from the group consisting of Ir(L A12 (L C1-II ) to Ir(L A98 )2(L C1416-II ); Each L Bk has a structure defined in List 6 below:

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

[0171] M(L A ) p (L B ) q (L C) r In some embodiments of the compounds having the formula, L A is L Ai selected from, i is an integer from 1 to 99, and L B is L Bk selected from, k is an integer from 1 to 836, and the compound is such that L Bk is the following: L B1 , L B2 , L B18 , L B28 , L B38 , L B108 , L B118 , L B122 , L B124 , L B126 , L B128 , L B130 , L B132 , L B134 , L B136 , L B138 , L B140 , L B142 , L B144 , L B156 , L B158 , L B160 , L B162 , L B164 , L B168 , L B172 , L B175 , L B204 , L B206 , L B214 , L B216 , L B218 , L B220 , L B222 , L B231 , L B233 , L B235 , L B237 , L B240 , L B242 , L B244 , L B246 , L B248 , L B250 , L B252 , L B254 , L B256 , L B258 , L B260 , L B262 , L B264 , L B265 , L B266 , L B267 , L B268 , L B269 , and LB270 It is selected from the group consisting of only the compound corresponding to one of them.

[0172] In some embodiments, the compound has its L Bk being as follows: L B1 L B2 L B18 L B28 L B38 L B108 L B118 L B122 L B126 L B128 L B132 L B136 L B138 L B142 L B156 L B162 L B204 L B206 L B214 L B216 L B218 L B220 L B231 L B233 L B237 L B264 L B265 L B266 L B267 L B268 L B269 and L B270 It is selected from the group consisting of only the compound corresponding to one of them.

[0173] In some embodiments, the compound is selected from the group consisting of only the compound having the L Cj-I or L Cj-II ligand, and its corresponding R 201 and R 202 are of the following structures: R D1 R D3 R D4 R D5 R D9 R D10 R D17 R D18 R D20 R D22 R D37 R D40 R D41 R D42 RD43 , R D48 , R D49 , R D50 , R D54 , R D55 , R D58 , R D59 , R D78 , R D79 , R D81 , R D87 , R D88 , R D89 , R D93 , R D116 , R D117 , R D118 , R D119 , R D120 , R D133 , R D134 , R D135 , R D136 , R D143 , R D144 , R D145 , R D146 , R D147 , R D149 , R D151 , R D154 , R D155 , R D161 , R D175 , R D190 , R D193 , R D200 , R D201 , R D206 , R D210 , R D214 , R D215 , R D216 , R D218 , R D219 , R D220 , R D227 , R D237 , R D241 , R D242 , R D245 , and R D246 is defined as being one of the following.

[0174] In some embodiments, the compound is selected from the group consisting of only compounds having a ligand of L Cj-I or L Cj-II and its corresponding R 201 and R 202 has the following structure: R D1 , R D3 , RD4 , R D5 , R D9 , R D10 , R D17 , R D22 , R D43 , R D50 , R D78 , R D116 , R D118 , R D133 , R D134 , R D135 , R D136 , R D143 , R D144 , R D145 , R D146 , R D149 , R D151 , R D154 , R D155 , R D190 , R D193 , R D200 , R D201 , R D206 , R D210 , R D214 , R D215 , R D216 , R D218 , R D219 , R D220 , R D227 , R D237 , R D241 , R D242 , R D245 and R D246 is defined as being one selected from.

[0175] In some embodiments, the compound is L Cj-I ligand has the following structure: [Chemical formula] is selected from the group consisting only of compounds having one of.

[0176] In some embodiments, the compound is Ir(L A )3, Ir(L A )2(L B ), Ir(L A )(L B )2, Ir(L A )2(L C ), and Ir(LA )(L B )(L C ) having a formula selected from the group consisting of. In some embodiments, L A is selected from the group consisting of the structures of List 1, List 2, and List 3, and L B is selected from the group consisting of the structures of List 4, List 5, and List 6 (L Bk ), and L C is selected from the group consisting of the structures of L Cj-I and L Cj-II defined herein.

[0177] In some embodiments, L A is selected from the group consisting of the structure of List 1, and L B is selected from the group consisting of the structure of L Bk . In some embodiments, L A is selected from the group consisting of the structure of List 2, and L B is selected from the group consisting of the structure of L Bk . In some embodiments, L A is selected from L of List 3 defined herein Ai , and L B is selected from the group consisting of the structure of L Bk , and k is an integer from 1 to 836. In some embodiments, L A is selected from List 3 defined herein, and L C is selected from the group consisting of the structures of L Cj-I and L Cj-II , where j is an integer from 1 to 1416.

[0178] In some embodiments, the compound is a compound of Ir(L A1 )3 to Ir(L A98 )3 of the formula Ir(L Ai )3, the formula Ir(L A )(L Bk ), the formula Ir(L Ai )(L B ), Ir(L A1 )(L B1 )2 to Ir(L A98 )(L B836)A compound of formula Ir(L Ai )(L Bk )2, a compound of formula Ir(L A )2(L Bk ),a compound of formula Ir(L Ai )2(L B ),Ir(L A1 )2(L B1 )~Ir(L A98 )2(L B836 ) compounds of formula Ir(L Ai )2(L Bk ),Ir(L A1 )2(L C1-I )~Ir(L A98 )2(L C1416-I ) compounds of formula Ir(L Ai )2(L Cj-I ),Ir(L A1 )2(L C1416-II )~Ir(L A98 )2(L C1416-II ) compounds of formula Ir(L Ai )2(L Cj-II ),Ir(L A1 )(L B1 )(L C1-I )~Ir(L A98 )(L B836 )(L C1416-I ) compounds of formula Ir(L Ai )(L Bk )(L Cj-I ),or Ir(L A1 )(L B1 )(L C1-II )~Ir(L A98 )(L B836 )(L C1416-II ) compounds of formula Ir(L Ai )(L Bk )(L Cj-II ),wherein L Ai ,L Bk ,as well as L Cj-I and L Cj-II are all defined herein.

[0179] In some embodiments, the compound has the structure of List 8 below:

Chemical Formula

Chem.

Chem.

Chem.

[0180] In some embodiments, the compound having the first ligand L of formula I described herein A can be at least 30% deuterated, at least 40% deuterated, at least 50% deuterated, at least 60% deuterated, at least 70% deuterated, at least 80% deuterated, at least 90% deuterated, at least 95% deuterated, at least 99% deuterated, or 100% deuterated. As used herein, the percent deuteration has its ordinary meaning and includes the percent of hydrogen atoms (e.g., positions that are hydrogen or deuterium) that can be replaced by deuterium atoms.

[0181] In some embodiments of the compound, L B is a substituted or unsubstituted phenylpyridine, and L C is a substituted or unsubstituted acetylacetonate.

[0182] In some embodiments of the compound, the ligand L B includes an electron-withdrawing group from the EWG1 list defined herein. In some embodiments, L B includes an electron-withdrawing group from the EWG2 list defined herein. In some embodiments, L B includes an electron-withdrawing group from the EWG3 list defined herein. In some embodiments, L B includes an electron-withdrawing group from the EWG4 list defined herein. In some embodiments, L B includes an electron-withdrawing group from the Pi-EWG list defined herein.

[0183] In some embodiments, ligand L C comprises an electron-withdrawing group from the EWG1 list defined herein. In some embodiments, L C comprises an electron-withdrawing group from the EWG2 list defined herein. In some embodiments, L C comprises an electron-withdrawing group from the EWG3 list defined herein. In some embodiments, L C comprises an electron-withdrawing group from the EWG4 list defined herein. In some embodiments, L C comprises an electron-withdrawing group from the Pi-EWG list defined herein.

[0184] In some embodiments, each of moiety A and moiety B can independently be a polycyclic fused-ring structure. In some embodiments, each of moiety A and moiety B can independently be a polycyclic fused-ring structure comprising at least three fused rings. In some embodiments, the polycyclic fused-ring structure has two 6-membered rings and one 5-membered ring. In some such embodiments, the 5-membered ring is fused to the ring coordinated to metal M, and the second 6-membered ring is fused to the 5-membered ring. In some embodiments, each of moiety A and moiety B can independently be selected from the group consisting of dibenzofuran, dibenzothiophene, dibenzoselenophene, and their aza-variants. In some such embodiments, each of moiety A and moiety B can independently be further substituted at the ortho or meta position of the O, S, or Se atom with a substituent selected from the group consisting of deuterium, fluorine, nitrile, alkyl, cycloalkyl, aryl, heteroaryl, and combinations thereof. In some such embodiments, the aza-variant contains exactly one N atom at the 6-position (ortho to O, S, or Se) and has a substituent at the 7-position (meta to O, S, or Se).

[0185] In some embodiments, each of moiety A and moiety B can independently be a polycyclic fused ring structure comprising at least four fused rings. In some embodiments, the polycyclic fused ring structure comprises three 6-membered rings and one 5-membered ring. In some such embodiments, the 5-membered ring is fused to the ring coordinated to metal M, the second 6-membered ring is fused to the 5-membered ring, and the third 6-membered ring is fused to the second 6-membered ring. In some such embodiments, the third 6-membered ring is further substituted by a substituent selected from the group consisting of deuterium, fluorine, nitrile, alkyl, cycloalkyl, aryl, heteroaryl, and combinations thereof.

[0186] In some embodiments, each of moiety A and moiety B can independently be a polycyclic fused ring structure comprising at least five fused rings. In some embodiments, the polycyclic fused ring structure comprises four 6-membered rings and one 5-membered ring, or three 6-membered rings and two 5-membered rings. In some embodiments comprising two 5-membered rings, the 5-membered rings are fused together. In some embodiments comprising two 5-membered rings, the 5-membered rings are separated by at least one 6-membered ring. In some embodiments having one 5-membered ring, the 5-membered ring is fused to the ring coordinated to metal M, the second 6-membered ring is fused to the 5-membered ring, the third 6-membered ring is fused to the second 6-membered ring, and the fourth 6-membered ring is fused to the third 6-membered ring.

[0187] In some embodiments, each of moiety A and moiety B can independently be an aza version of the above polycyclic fused ring. In some such embodiments, each of moiety A and moiety B can independently contain exactly one aza N atom. In some such embodiments, each of moiety A and moiety B contains exactly two aza N atoms, which can be present in one ring or in two different rings. In some such embodiments, the ring having an aza N atom is separated from the metal M atom by at least two other rings. In some such embodiments, the ring having an aza N atom is separated from the metal M atom by at least three other rings. In some such embodiments, each of the ortho positions of the aza N atom is substituted.

[0188] In some embodiments, the first ligand L of formula I described herein A The compound having can be at least 30% deuterated, at least 40% deuterated, at least 50% deuterated, at least 60% deuterated, at least 70% deuterated, at least 80% deuterated, at least 90% deuterated, at least 95% deuterated, at least 99% deuterated, or 100% deuterated. As used herein, the percent deuteration has its ordinary meaning and includes the percent of hydrogen atoms (e.g., positions that are hydrogen or deuterium) that can be replaced by deuterium atoms.

[0189] In some embodiments of the heteroleptic compound having the formula M(L A ) p (L B ) q (L C ) r the ligand L A has a first substituent R I and the first substituent R I has a first atom a-I that is the farthest from the metal M among all the atoms in the ligand L A . Further, the ligand L B has a second substituent R II when present, and the second substituent RII has a first atom a-II that is the farthest from the metal M among all the atoms in the ligand L B . Further, the ligand L C , when present, has a third substituent R III , and the third substituent R III has a first atom a-III that is the farthest from the metal M among all the atoms in the ligand L C .

[0190] In such a heteroleptic compound, vectors V D1 , V D2 , and V D3 can be defined. V D1 represents the direction from the metal M to the first atom a-I, and the vector V D1 has a value D I that represents the straight-line distance between the metal M and the first atom a-I in the first substituent R 1 . V D2 represents the direction from the metal M to the first atom a-II, and the vector V D2 has a value D II that represents the straight-line distance between the metal M and the first atom a-II in the second substituent R 2 . V D3 represents the direction from the metal M to the first atom a-III, and the vector V D3 has a value D III that represents the straight-line distance between the metal M and the first atom a-III in the third substituent R 3 .

[0191] In such a heteroleptic compound, a sphere having a radius r has its center at the metal M, and the radius r is defined as the minimum radius that enables the sphere to surround all the atoms in the compound that are not part of the substituents R I , R II , and R III ; at least one of D 1 , D 2 , and D 3 is at least 1.5 Å greater than the radius r. In some embodiments, D 1 , D 2 , and D3 At least one of them is at least 2.9, 3.0, 4.3, 4.4, 5.2, 5.9, 7.3, 8.8, 10.3, 13.1, 17.6, or 19.1 Å larger than the radius r.

[0192] In some embodiments of such heteroleptic compounds, the compound has a transition dipole moment axis, and the angle is defined between the transition dipole moment axis and the vectors V D1 V D2 and V D3 and at least one of the angles between the transition dipole moment axis and the vectors V D1 V D2 and V D3 is less than 40°. In some embodiments, at least one of the angles between the transition dipole moment axis and the vectors V D1 V D2 and V D3 is less than 30°. In some embodiments, at least one of the angles between the transition dipole moment axis and the vectors V D1 V D2 and V D3 is less than 20°. In some embodiments, at least one of the angles between the transition dipole moment axis and the vectors V D1 V D2 and V D3 is less than 15°. In some embodiments, at least one of the angles between the transition dipole moment axis and the vectors V D1 V D2 and V D3 is less than 10°. In some embodiments, at least two of the angles between the transition dipole moment axis and the vectors V D1 V D2 and V D3 are less than 20°. In some embodiments, at least two of the angles between the transition dipole moment axis and the vectors V D1 V D2 and V D3 are less than 15°. In some embodiments, at least two of the angles between the transition dipole moment axis and the vectors V D1 VD2 and V D3 At least two of the angles between them are less than 10°.

[0193] In some embodiments, the transition dipole moment axis and the vector V D1 V D2 and V D3 All three angles between and V are less than 20°. In some embodiments, the transition dipole moment axis and the vector V D1 V D2 and V D3 All three angles between and V are less than 15°. In some embodiments, the transition dipole moment axis and the vector V D1 V D2 and V D3 All three angles between and V are less than 10°.

[0194] One of ordinary skill in the art will readily understand the meaning of the terms transition dipole moment axis of a compound and vertical dipole ratio of a compound. Nevertheless, the meaning of these terms can be found in U.S. Patent No. 10,672,997, the disclosure of which is incorporated herein by reference in its entirety. U.S. Patent No. 10,672,997 discusses the horizontal dipole ratio (HDR) of a compound rather than the VDR. However, one of ordinary skill in the art will readily understand that VDR = 1 - HDR.

[0195] C. OLEDs and Devices of the Present Disclosure In another aspect, the present disclosure also provides an OLED device including a first organic layer including a compound disclosed in the section of the above compounds of the present disclosure.

[0196] In some embodiments, the OLED includes an anode; a cathode; and an organic layer disposed between the anode and the cathode, the organic layer including a compound having a first ligand L A and the first ligand L A has the structure of Formula I:

Chemical formula

Chemical formula

[0197] In some embodiments of the OLED, the organic layer is a light-emitting layer, and the compound can be a light-emitting dopant or a non-light-emitting dopant.

[0198] In some embodiments of the OLED, the organic layer further contains a host, and the host contains a triphenylene-containing benzocondensed thiophene or benzocondensed furan; any substituent in the host is C n H 2n+1 , OC n H 2n+1 , OAr1, N(C n H 2n+1 )2, N(Ar1)(Ar2), CH=CH-C n H 2n+1 , C≡CCn H 2n+1 、 Ar1, Ar1 - Ar2, C n H 2n is a non - condensed substituent independently selected from the group consisting of -Ar1 or is unsubstituted; In the formula, n is an integer from 1 to 10, and Ar1 and Ar2 are independently selected from the group consisting of benzene, biphenyl, naphthalene, triphenylene, carbazole, and their heteroaromatic analogs.

[0199] In some embodiments, the organic layer may be a light - emitting layer, and the compounds described herein may be a light - emitting dopant or a non - light - emitting dopant.

[0200] In some embodiments, the light - emitting layer contains one or more quantum dots.

[0201] In some embodiments, the organic layer may further contain a host, the host contains triphenylene - containing benzocondensed thiophene or benzocondensed furan, and any substituent in the host is C n H 2n+1 、 OC n H 2n+1 、 OAr1, N(C n H 2n+1 )2, N(Ar1)(Ar2), CH = CH - C n H 2n+1 、 C≡CC n H 2n+1 、 Ar1, Ar1 - Ar2, C n H 2n is a non - condensed substituent independently selected from the group consisting of -Ar1 or is unsubstituted, where n is an integer from 1 to 10; Ar1 and Ar2 are independently selected from the group consisting of benzene, biphenyl, naphthalene, triphenylene, carbazole, and their heteroaromatic analogs.

[0202] In some embodiments, the organic layer may further contain a host, the host is triphenylene, carbazole, indolocarbazole, dibenzothiophene, dibenzofuran, dibenzoselenophene, 5λ 2-benzo[d]benzo[4,5]imidazo[3,2-a]imidazole, 5,9-dioxa-13b-boranaphtho[3,2,1-de]anthracene, triazine, boryl, silyl, aza-triphenylene, aza-carbazole, aza-indolocarbazole, aza-dibenzothiophene, aza-dibenzofuran, aza-dibenzoselenophene, aza-5λ 2 -benzo[d]benzo[4,5]imidazo[3,2-a]imidazole, and at least one chemical group selected from the group consisting of aza-(5,9-dioxa-13b-boranaphtho[3,2,1-de]anthracene).

[0203] In some embodiments, the host has the structure of Host Group 1 below:

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

[0204] In some embodiments, L’ is an organic linker selected from the group consisting of BR, BRR’, NR, PR, P(O)R, O, S, Se, C=O, C=S, C=Se, C=NR, C=CRR’, S=O, SO2, CR, CRR’, SiRR’, GeRR’, alkylene, cycloalkyl, aryl, cycloalkylene, arylene, heteroarylene, and combinations thereof.

[0205] In some embodiments, the host can be selected from host group 2 consisting of:

Chemical formula

Chemical formula

[0206] In some embodiments, the organic layer may further include a host, and the host includes a metal complex.

[0207] In some embodiments, the light-emitting layer may include two hosts, a first host and a second host. In some embodiments, the first host is a hole-transporting host, and the second host is an electron-transporting host. In some embodiments, the first host and the second host may form an exciplex.

[0208] In some embodiments, the compounds described herein may be sensitizers; the device may further include an acceptor; and the acceptor may be selected from the group consisting of a fluorescent emitter, a delayed fluorescent emitter, and combinations thereof.

[0209] In yet another aspect, the OLEDs of the present disclosure may also include a light-emitting region comprising a compound disclosed in the section of the compounds of the present disclosure above. In some embodiments, the light-emitting region comprises a compound having a first ligand L A and the first ligand L A has the structure of Formula I:

Chemical Formula

[0210] In some embodiments, at least one of the anode, cathode, or a new layer disposed on the organic light-emitting layer functions as an enhancement layer. The enhancement layer includes a plasmonic material that non-radiatively couples to the emitter material and exhibits surface plasmon resonance that transfers excited state energy from the emitter material to surface plasmon polaritons in a non-radiative mode. The enhancement layer is provided within a threshold distance from the organic light-emitting layer, and the emitter material has a total non-radiative decay rate constant and a total radiative decay rate constant due to the presence of the enhancement layer, and at the threshold distance, the total non-radiative decay rate constant is equal to the total radiative decay rate constant. In some embodiments, the OLED further includes an outcoupling layer. In some embodiments, the outcoupling layer is disposed on the enhancement layer on the opposite side of the organic light-emitting layer. In some embodiments, the outcoupling layer is disposed on the opposite side of the enhancement layer of the light-emitting layer but still outcouples energy from the surface plasmon mode of the enhancement layer. The outcoupling layer scatters energy from the surface plasmon polaritons. In some embodiments, this energy is scattered into free space as photons. In other embodiments, the energy is scattered from the surface plasmon mode into other modes of the device, including but not limited to organic waveguide modes, substrate modes, or other waveguide modes. If the energy is scattered into a non-free space mode of the OLED, other outcoupling schemes can be incorporated to extract that energy into free space. In some embodiments, one or more intervening layers can be disposed between the enhancement layer and the outcoupling layer. Examples of the intervening layer may be a dielectric material including organic, inorganic, perovskite, oxides, and may include laminates and / or mixtures of these materials.

[0211] The enhancement layer changes the effective properties of the medium in which the emitter material is present, resulting in any or all of a decrease in the emission rate, a change in the emission line shape, a change in the emission intensity with angle, a change in the stability of the emitter material, a change in the efficiency of the OLED, and a reduction in the efficiency roll-off of the OLED device. When the enhancement layer is disposed on the cathode side, the anode side, or both sides, an OLED device that utilizes any of the above effects can be obtained. In addition to the specific functional layers shown in the various OLED examples described and illustrated herein, the OLEDs according to the present disclosure may include any of the other functional layers often seen in OLEDs.

[0212] The enhancement layer may be composed of a plasmonic material, an optically active metamaterial, or a hyperbolic metamaterial. As used herein, a plasmonic material is a material in which the real part of the dielectric constant crosses zero in the visible or ultraviolet region of the electromagnetic spectrum. In some embodiments, the plasmonic material includes at least one metal. In such embodiments, the metal may include at least one of Ag, Al, Au, Ir, Pt, Ni, Cu, W, Ta, Fe, Cr, Mg, Ga, Rh, Ti, Ru, Pd, In, Bi, Ca alloys, or mixtures of these materials, and laminates of these materials. Generally, a metamaterial is a medium composed of different materials, and as a whole medium, it functions differently from the sum of its material parts. In particular, an optically active metamaterial is defined as a material having both a negative dielectric constant and a negative magnetic permeability. On the other hand, a hyperbolic metamaterial is an anisotropic medium having different signs for different spatial directions of the dielectric constant or the magnetic permeability. Optically active metamaterials and hyperbolic metamaterials are strictly distinguished from many other photonic structures such as distributed Bragg reflectors ("DBRs") in that the medium should appear uniform in the propagation direction on the length scale of the wavelength of light. Using terms that can be understood by those skilled in the art, the dielectric constant of the metamaterial in the propagation direction can be described using the effective medium approximation. Plasmonic materials and metamaterials provide ways to control the propagation of light that can enhance OLED performance in many ways.

[0213] In some embodiments, the enhancement layer is provided as a planar layer. In other embodiments, the enhancement layer has wavelength-sized features arranged periodically, quasi-periodically, or randomly, or sub-wavelength-sized features arranged periodically, quasi-periodically, or randomly. In some embodiments, the wavelength-sized features and the sub-wavelength-sized features have sharp edges.

[0214] In some embodiments, the outcoupling layer has wavelength-sized features arranged periodically, quasi-periodically, or randomly, or sub-wavelength-sized features arranged periodically, quasi-periodically, or randomly. In some embodiments, the outcoupling layer may be composed of a plurality of nanoparticles, and in other embodiments, the outcoupling layer is composed of a plurality of nanoparticles disposed on a material. In these embodiments, the outcoupling layer can be adjusted by at least one of changing the size of the plurality of nanoparticles, changing the shape of the plurality of nanoparticles, changing the material of the plurality of nanoparticles, adjusting the thickness of the material, changing the refractive index of the material, or adding an additional layer on the plurality of nanoparticles, changing the thickness of the enhancement layer, and / or changing the material of the enhancement layer. The plurality of nanoparticles of the device can be formed from at least one of a metal, a dielectric material, a semiconductor material, an alloy of a metal, a mixture of dielectric materials, a laminate or layer of one or more materials, and / or a core of a certain type of material coated with a shell of another type of material. In some embodiments, the outcoupling layer is composed of at least metal nanoparticles, and the metal is selected from the group consisting of Ag, Al, Au, Ir, Pt, Ni, Cu, W, Ta, Fe, Cr, Mg, Ga, Rh, Ti, Ru, Pd, In, Bi, Ca, alloys or mixtures of these materials, and laminates of these materials. The plurality of nanoparticles may have additional layers disposed thereon. In some embodiments, the polarization of the emission can be adjusted using the outcoupling layer. By varying the dimensionality and periodicity of the outcoupling layer, the type of polarization that is preferentially outcoupled to air can be selected. In some embodiments, the outcoupling layer also functions as an electrode of the device.

[0215] In yet another aspect, the present disclosure also provides a consumer product comprising an organic light emitting device (OLED) having an anode; a cathode; and an organic layer disposed between the anode and the cathode, wherein the organic layer can include a compound disclosed in the section of the compounds of the present disclosure.

[0216] In some embodiments, the consumer product includes an OLED having an anode; a cathode; and an organic layer disposed between the anode and the cathode, the organic layer having a first ligand L having the structure of Formula I described herein A and may include a compound having the same.

[0217] In some embodiments, the consumer product is a flat panel display, a computer monitor, a medical monitor, a television, a billboard, an indoor or outdoor lighting and / or signaling light, a head-up display, a fully or partially transparent display, a flexible display, a laser printer, a telephone, a cellular phone, a tablet, a phablet, a personal digital assistant (PDA), a wearable device, a laptop computer, a digital camera, a camcorder, a viewfinder, a microdisplay (display less than 2 inches diagonal), a 3-D display, a virtual reality or augmented reality display, a vehicle, a video wall including multiple displays arranged side by side, a theater or stadium screen, a phototherapy device, and a signboard, and may be one of them.

[0218] Generally, an OLED includes at least one organic layer disposed between and electrically connected to an anode and a cathode. When a current is applied, the anode injects holes and the cathode injects electrons into the organic layer(s). The injected holes and electrons move respectively towards the oppositely charged electrodes. When an electron and a hole are localized on the same molecule, an "exciton", which is a localized electron-hole pair having an excited energy state, is formed. Light is emitted via a photoelectron emission mechanism when the exciton relaxes. In some cases, the exciton may be localized as an excimer or an exciplex. Non-radiative mechanisms such as thermal relaxation may occur, but are generally considered undesirable.

[0219] Several OLED materials and configurations are described in U.S. Patent Nos. 5,844,363, 6,303,238, and 5,707,745, which are hereby incorporated by reference in their entirety.

[0220] Initial OLEDs used luminescent molecules that emit light (''fluorescence'') from their singlet state, as disclosed, for example, in U.S. Patent No. 4,769,292, which is hereby incorporated by reference in its entirety. Fluorescent emission generally occurs within a time frame of less than 10 nanoseconds.

[0221] More recently, OLEDs having luminescent materials (''phosphorescence'') that emit light from the triplet state have been demonstrated. Baldo et al., ''Highly Efficient Phosphorescent Emission from Organic Electroluminescent Devices'', Nature, Vol. 395, 151 - 154, 1998; (''Baldo-I'') and Baldo et al., ''Very high-efficiency green organic light-emitting devices based on electrophosphorescence'', Appl. Phys. Lett., Vol. 75, No. 3, 4 - 6 (1999) (''Baldo-II'') are hereby incorporated by reference in their entirety. Phosphorescence is described in further detail in columns 5 - 6 of U.S. Patent No. 7,279,704, which is hereby incorporated by reference.

[0222] Figure 1 shows an organic light emitting device 100. The figure is not necessarily drawn to scale. The device 100 may include a substrate 110, an anode 115, a hole injection layer 120, a hole transport layer 125, an electron blocking layer 130, a light emitting layer 135, a hole blocking layer 140, an electron transport layer 145, an electron injection layer 150, a protective layer 155, a cathode 160, and a barrier layer 170. The cathode 160 is a composite cathode having a first conductive layer 162 and a second conductive layer 164. The device 100 may be fabricated by sequentially depositing the described layers. The characteristics, functions, and material examples of these various layers are described in further detail in U.S. Patent No. 7,279,704, incorporated by reference, in columns 6 - 10.

[0223] For each of these layers, further examples are available. For example, the flexible and transparent substrate-anode combination is disclosed in U.S. Patent No. 5,844,363, which is incorporated herein by reference in its entirety. An example of a p-doped hole transport layer is one doped with F4-TCNQ at a molar ratio of 50:1 as disclosed in U.S. Patent Application Publication No. 2003 / 0230980, which is incorporated herein by reference in its entirety. Examples of the light-emitting material and the host material are disclosed in U.S. Patent No. 6,303,238 to Thompson et al., which is incorporated herein by reference in its entirety. An example of an n-doped electron transport layer is one doped with Li at a molar ratio of 1:1 as disclosed in U.S. Patent Application Publication No. 2003 / 0230980, which is incorporated herein by reference in its entirety. U.S. Patent Nos. 5,703,436 and 5,707,745, which are incorporated herein by reference in their entireties, disclose examples of cathodes including a composite cathode having a thin layer of a metal such as Mg:Ag having a transparent, conductive, sputter-deposited ITO layer thereon. The theory and use of the blocking layer are described in more detail in U.S. Patent No. 6,097,147 and U.S. Patent Application Publication No. 2003 / 0230980, which are incorporated herein by reference in their entireties. Examples of the injection layer are provided in U.S. Patent Application Publication No. 2004 / 0174116, which is incorporated herein by reference in its entirety. A description of the protective layer can be found in U.S. Patent Application Publication No. 2004 / 0174116, which is incorporated herein by reference in its entirety.

[0224] Figure 2 shows an inverted OLED 200. The device includes a substrate 210, a cathode 215, a light-emitting layer 220, a hole transport layer 225, and an anode 230. The device 200 can be fabricated by depositing the described layers in sequence. The most common OLED configuration has a cathode disposed on top of the anode, and since the device 200 has a cathode 215 disposed under the anode 230, the device 200 can be referred to as an “inverted” OLED. Materials similar to those described for the device 100 may be used in the corresponding layers of the device 200. Figure 2 provides an example of how some layers can be omitted from the structure of the device 100.

[0225] The simple layer structures illustrated in FIGS. 1 and 2 are provided as non-limiting examples, and it is understood that embodiments of the present disclosure can be used in connection with a wide variety of other structures. The specific materials and structures described are exemplary in nature, and other materials and structures may be used. Functional OLEDs can be realized by combining the various layers described in various ways, or the layers can be omitted entirely based on design, performance, and cost factors. Other layers not specifically described may also be included. Materials other than those specifically described may be used. Many of the examples provided herein describe the various layers as including a single material, but it is understood that combinations of materials such as mixtures of hosts and dopants, or more generally mixtures, may be used. Also, the layers may have various sub-layers. The names given to the various layers herein are not intended to be strictly limiting. For example, in the device 200, the hole transport layer 225 transports holes and injects holes into the light-emitting layer 220 and can be described as a hole transport layer or a hole injection layer. In one embodiment, an OLED can be described as having an “organic layer” disposed between the cathode and the anode. This organic layer can include a single layer or can further include multiple layers of different organic materials such as those described with respect to FIGS. 1 and 2.

[0226] Structures and materials not specifically described may be used, such as OLEDs (PLEDs) composed of polymer materials like those disclosed in Friend et al.'s U.S. Patent No. 5,247,190, which is incorporated by reference in its entirety. As a further example, an OLED having a single organic layer may be used. The OLEDs may be stacked, for example, as described in Forrest et al.'s U.S. Patent No. 5,707,745, which is incorporated by reference in its entirety. The OLED structure may deviate from the simple layer structures illustrated in FIGS. 1 and 2. For example, the substrate may include angled reflective surfaces for improving out-coupling, such as the mesa structure described in Forrest et al.'s U.S. Patent No. 6,091,195, which is incorporated by reference in its entirety, and / or the recessed structure described in Bulovic et al.'s U.S. Patent No. 5,834,893, which is incorporated by reference in its entirety.

[0227] Unless otherwise specified, any of the layers of the various embodiments can be deposited by any suitable method. For organic layers, preferred methods include thermal evaporation such as those described in U.S. Pat. Nos. 6,013,982 and 6,087,196, which are incorporated herein by reference in their entirety, inkjet, organic vapor deposition (OVPD) such as those described in U.S. Pat. No. 6,337,102 to Forrest et al., which is incorporated herein by reference in its entirety, and organic vapor jet printing (also referred to as OVJP, organic vapor jet deposition (OVJD)) such as those described in U.S. Pat. No. 7,431,968, which is incorporated herein by reference in its entirety. Other suitable deposition methods include spin coating and other solution-based processes. Solution-based processes are preferably performed in a nitrogen or inert atmosphere. For other layers, preferred methods include thermal evaporation. Preferred patterning methods include masks such as those described in U.S. Pat. Nos. 6,294,398 and 6,468,819, which are incorporated herein by reference in their entirety, deposition via cold welding, and patterning related to some of the deposition methods such as inkjet and organic vapor jet printing (OVJP). Other methods may be used. The materials to be deposited can be modified to be compatible with the particular deposition method. For example, substituents such as alkyl and aryl groups that are branched or unbranched and preferably contain at least 3 carbons can be used in small molecules to enhance the ability to undergo solution processing. Substituents having 20 or more carbons can be used, and a range of 3 to 20 carbons is preferred. Materials having an asymmetric structure can have better solution processability than those having a symmetric structure because the asymmetric materials may have a lower tendency to recrystallize. Dendrimer substituents can be used to enhance the ability of small molecules to undergo solution processing.

[0228] Devices fabricated in accordance with embodiments of the present disclosure may optionally further include a barrier layer. One purpose of the barrier layer is to protect the electrodes and organic layers from damaging exposure to harmful species in an environment containing moisture, vapor, and / or gas, etc. The barrier layer can be deposited on the substrate, above, below, or adjacent to the electrodes, or on any other part of the device including the edges. The barrier layer may include a single layer or multiple layers. The barrier layer can be formed by various known chemical vapor deposition techniques and can include compositions having a single phase and compositions having multiple phases. Any suitable material or combination of materials may be used for the barrier layer. The barrier layer may incorporate inorganic or organic compounds or both. Preferred barrier layers include a mixture of polymeric and non-polymeric materials as described in U.S. Patent No. 7,968,146, PCT Patent Application Nos. PCT / US2007 / 023098 and PCT / US2009 / 042829, which are hereby incorporated by reference in their entirety. For the mixture to be considered a "mixture", the polymeric and non-polymeric materials comprising the barrier layer should be deposited under the same reaction conditions and / or simultaneously. The weight ratio of the polymeric material to the non-polymeric material can range from 95:5 to 5:95. The polymeric and non-polymeric materials can be made from the same precursor material. In one example, the mixture of polymeric and non-polymeric materials consists essentially of polymeric silicon and inorganic silicon.

[0229] Devices fabricated in accordance with embodiments of the present disclosure can be incorporated into a wide variety of electronic component modules (or units) that can be incorporated into various electrical products or intermediate components. Examples of such electrical products or intermediate components include display screens, lighting devices, such as discrete light source devices or lighting panels, etc., that can be utilized by end-user product manufacturers. Such electronic component modules can optionally include drive electronics and / or power supplies. Devices fabricated in accordance with embodiments of the present disclosure can be incorporated into a wide variety of consumer products having one or more incorporated electronic component modules (or units). Consumer products including OLEDs containing the compounds of the present disclosure in the organic layers of the OLEDs are disclosed. Such consumer products include any type of product including one or more light sources and / or one or more certain types of visual displays. Some examples of such consumer products include flat panel displays, curved displays, computer monitors, medical monitors, televisions, bulletin boards, indoor or outdoor lighting and / or signal sending lights, head-up displays, fully or partially transparent displays, flexible displays, bendable displays, foldable displays, stretchable displays, laser printers, telephones, mobile phones, tablets, phablets, personal digital assistants (PDAs), wearable devices, laptop computers, digital cameras, camcorders, viewfinders, microdisplays (displays less than 2 inches diagonal), 3-D displays, virtual reality or augmented reality displays, vehicles, video walls including multiple displays arranged side by side, theater or stadium screens, light therapy devices, and billboards. The devices fabricated in accordance with the present disclosure can be controlled using a variety of control mechanisms, including passive matrix and active matrix. Many of the devices are intended for use within a temperature range comfortable for humans, such as from 18°C to 30°C, more preferably room temperature (20 - 25°C), although they can also be used outside this temperature range, for example, from -40°C to +80°C Celsius.

[0230] Further details regarding OLEDs, and the above definitions, can be found in U.S. Patent No. 7,279,704, which is hereby incorporated by reference in its entirety.

[0231] The materials and structures described herein may have applications in devices other than OLEDs. For example, other optoelectronic devices such as organic solar cells and organic photodetectors may utilize the materials and structures. More generally, organic devices such as organic transistors may utilize the materials and structures.

[0232] In some embodiments, the OLED has one or more characteristics selected from the group consisting of being flexible, rollable, foldable, stretchable, and bendable. In some embodiments, the OLED is transparent or translucent. In some embodiments, the OLED further includes a layer comprising carbon nanotubes.

[0233] In some embodiments, the OLED further includes a layer comprising a delayed fluorescence emitter. In some embodiments, the OLED includes an RGB pixel array or a white and color filter pixel array. In some embodiments, the OLED is a mobile device, a handheld device, or a wearable device. In some embodiments, the OLED is a display panel having a diagonal less than 10 inches or an area less than 50 square inches. In some embodiments, the OLED is a display panel having a diagonal of at least 10 inches or an area of 50 square inches. In some embodiments, the OLED is an illumination panel.

[0234] In some embodiments, the compound can be a luminescent dopant. In some embodiments, the compound can generate luminescence via phosphorescence, fluorescence, thermally activated delayed fluorescence, i.e., TADF (also referred to as E-type delayed fluorescence; see, e.g., U.S. Application No. 15 / 700,352, which is hereby incorporated by reference in its entirety), triplet-triplet annihilation, or a combination of these processes. In some embodiments, the luminescent dopant can be a racemic mixture or enriched in one enantiomer. In some embodiments, the compound can be homoleptic (each ligand is the same). In some embodiments, the compound can be heteroleptic (at least one ligand is different from the others). If there are multiple ligands coordinated to the metal, in some embodiments, all of the ligands can be the same. In some other embodiments, at least one ligand is different from the other ligands. In some embodiments, all of the ligands can be different from each other. This also applies to embodiments where the ligands coordinated to the metal can be linked to other ligands coordinated to the same metal to form tridentate, tetradentate, pentadentate, or hexadentate ligands. Thus, when the coordinated ligands are linked together, in some embodiments, all of the ligands can be the same, and in some other embodiments, at least one of the linked ligands can be different from the other ligands.

[0235] In some embodiments, the compound can be used as a phosphorescence sensitizer in an OLED in which one or more layers in the OLED contain an acceptor in the form of one or more fluorescent and / or delayed fluorescence emitters. In some embodiments, the compound can be used as one component of an exciplex to be used as a sensitizer. As a phosphorescence sensitizer, this compound must be capable of energy transfer to the acceptor, and the acceptor will either emit energy or further transfer the energy to the final emitter. The concentration of the acceptor can range from 0.001% to 100%. The acceptor can be present in either the same layer as the phosphorescence sensitizer or in one or more different layers. In some embodiments, the acceptor is a TADF emitter. In some embodiments, the acceptor is a fluorescent emitter. In some embodiments, the emission can occur from any or all of the sensitizer, acceptor, and final emitter.

[0236] According to another aspect, a formulation comprising the compounds described herein is also disclosed.

[0237] The OLEDs disclosed herein can be incorporated into one or more of consumer products, electronic component modules, and lighting panels. In some embodiments, the organic layer can be a light-emitting layer, the compound can be a luminescent dopant, while in other embodiments, the compound can be a non-luminescent dopant.

[0238] In yet another aspect of the present disclosure, a formulation comprising the novel compounds disclosed herein is described. The formulation can include one or more components selected from the group consisting of the solvents, hosts, hole injection materials, hole transport materials, electron blocking materials, hole blocking materials, and electron transport materials disclosed herein.

[0239] The present disclosure encompasses any chemical structure containing the novel compounds of the present disclosure, or their monovalent or polyvalent variants. In other words, the compounds of the present invention, or their monovalent or polyvalent variants, can be part of a larger chemical structure. Such chemical structures can be selected from the group consisting of monomers, polymers, macromolecules, and supramolecules (also known as giant molecules). As used herein, "monovalent variant of a compound" refers to a moiety that is identical to the said compound except that one hydrogen has been removed and replaced by a bond to the rest of the chemical structure. As used herein, "polyvalent variant of a compound" refers to a moiety that is identical to the said compound except that two or more hydrogens have been removed and replaced by bonds to the rest of the chemical structure. In the example of a supramolecule, the compounds of the present invention can also be incorporated into the supramolecular complex without covalent bonds.

[0240] D. Combinations of Compounds of the Present Disclosure with Other Materials The materials described herein as useful for a particular layer in an organic light-emitting device can be used in combination with a wide variety of other materials present in the device. For example, the emissive dopants disclosed herein can be used in combination with a wide variety of hosts, transport layers, blocking layers, injection layers, electrodes, and other layers that may be present. The materials described or referred to below are non-limiting examples of materials that can be useful in combination with the compounds disclosed herein, and one of ordinary skill in the art can readily refer to the literature to identify other materials that can be useful in combination.

[0241] a) Conductive (Electrically Conductive) Dopants: The charge transport layer is doped with a conductive dopant to greatly change the density of charge carriers and thereby its conductivity. Conductivity is increased by generating charge carriers in the matrix material, and depending on the type of dopant, a change in the Fermi level of the semiconductor can also be achieved. The hole transport layer can be doped with a p-type conductive dopant, and an n-type conductive dopant is used in the electron transport layer.

[0242] Non-limiting examples of conductive dopants that can be used in an OLED in combination with the materials disclosed herein are illustrated below together with the references that disclose these materials: EP01617493, EP01968131, EP2020694, EP2684932, US20050139810, US20070160905, US20090167167, US2010288362, WO06081780, WO2009003455, WO2009008277, WO2009011327, WO2014009310, US2007252140, US2015060804, US20150123047, and US2012146012.

Chemical formula

[0243] b) HIL / HTL: The hole injection / transport materials to be used in the present disclosure are not particularly limited, and any compound can be used as long as it is a compound usually used as a hole injection / transport material. Examples of the materials include phthalocyanine or porphyrin derivatives; aromatic amine derivatives; indolocarbazole derivatives; polymers containing fluorinated hydrocarbons; polymers having a conductive dopant; conductive polymers such as PEDOT / PSS; self-assembled monomers derived from compounds such as phosphonic acids and silane derivatives; metal oxide derivatives such as MoO x and the like; p-type semiconductor organic compounds such as 1,4,5,8,9,12-hexaazatriphenylene hexacarbonitrile; metal complexes, and crosslinkable compounds, but are not limited thereto.

[0244] Examples of the aromatic amine derivatives used in the HIL or HTL include the following general structure:

Chemical formula

[0245] Ar 1 ~Ar 9Each of them is selected from the group consisting of aromatic hydrocarbon cyclic compounds such as benzene, biphenyl, triphenyl, triphenylene, naphthalene, anthracene, phenalene, phenanthrene, fluorene, pyrene, chrysene, perylene, and azulene; dibenzothiophene, dibenzofuran, dibenzoselenophene, furan, thiophene, benzofuran, benzothiophene, benzoselenophene, carbazole, indolocarbazole, pyridylindole, 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, phenoxazine, benzofuropyridine, furodipyridine, benzothienopyridine, thienodipyridine, benzoselenophenopyridine, and selenophenodipyridine; and the same or different types of groups selected from aromatic hydrocarbon cyclic groups and aromatic heterocyclic groups, and directly or through at least one of an oxygen atom, a nitrogen atom, a sulfur atom, a silicon atom, a phosphorus atom, a boron atom, a chain structural unit, and an aliphatic cyclic group, and are selected from the group consisting of 2 to 10 cyclic structural units bonded to each other. Each Ar may be unsubstituted or substituted by a substituent selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof.

[0246] In one aspect, Ar 1 ~Ar9 independently, [Chemical formula] (wherein k is an integer from 1 to 20; X 101 ~X 108 is C (including C(CH)) or N; Z 101 is NAr 1 O, or S; Ar 1 has the same group defined above) and is selected from the group consisting of.

[0247] Examples of metal complexes used in HIL or HTL include the following general formula: [Chemical formula] (wherein Met is a metal that can have an atomic weight greater than 40; (Y 101 -Y 102 ) is a bidentate ligand, and Y 101 and Y 102 are independently selected from C, N, O, P, and S; L 101 is a co-ligand; k' is an integer value from 1 to the maximum number of ligands that can bind to the metal; and k'+k'' is the maximum number of ligands that can bind to the metal), but are not limited thereto.

[0248] In one aspect, (Y 101 -Y 102 ) is a 2-phenylpyridine derivative. In another aspect, (Y 101 -Y 102 ) is a carbene ligand. In another aspect, Met is selected from Ir, Pt, Os, and Zn. In a further aspect, the metal complex has a minimum oxidation potential of less than about 0.6 V in solution with respect to the Fc + / Fc couple.

[0249] Non-limiting examples of HIL materials and HTL materials that can be used in OLEDs in combination with the materials disclosed in this specification are the references that disclose these materials: CN102702075, DE102012005215, EP01624500, EP01698613, EP01806334, EP01930964, EP01972613, EP01997799, EP02011790, EP02055700, EP02055701, EP1725079, EP2085382, EP2660300, EP650955, JP07-073529, JP2005112765, JP2007091719, JP2008021687, JP2014-009196, KR20110088898, KR20130077473, TW201139402, US06517957, US20020158242, US20030162053, US20050123751, US20060182993, US20060240279, US20070145888, US20070181874, US20070278938, US20080014464, US20080091025, US20080106190, US20080124572, US20080145707, US20080220265, US20080233434, US20080303417, US2008107919, US20090115320, US20090167161, US2009066235, US2011007385, US20110163302, US2011240968, US2011278551, US2012205642, US2013241401, US20140117329, US2014183517, US5061569, US5639914, WO05075451, WO07125714, WO08023550, WO08023759, WO2009145016, WO2010061824, WO2011075644, WO2012177006, WO2013018530, WO2013039073, WO2013087142, WO2013118812, WO2013120577, WO2013157367, WO2013175747, WO2014002873, WO2014015935, WO2014015937, WO2014030872,Illustrated below together with WO2014030921, WO2014034791, WO2014104514, and WO2014157018.

Chem.

Chem.

Chem.

Chem.

Chem.

[0250] c) EBL: The electron blocking layer (EBL) can be used to reduce the number of electrons and / or excitons exiting the light-emitting layer. The presence of such a blocking layer in a device can result in significantly higher efficiency and / or longer lifetime compared to a similar device lacking the blocking layer. Also, a blocking layer can be used to limit light emission to a desired region of the OLED. In some embodiments, the EBL material has a higher LUMO (closer to the vacuum level) and / or higher triplet energy than the emitter closest to the EBL interface. In some embodiments, the EBL material has a higher LUMO (closer to the vacuum level) and / or higher triplet energy than one or more of the hosts closest to the EBL interface. In one aspect, the compound used in the EBL contains the same molecule or the same functional group as that used as one of the hosts described below.

[0251] d) Host: The light-emitting layer of the organic EL device of the present disclosure preferably contains at least a metal complex as a light-emitting material and may contain a host material using the metal complex as a dopant material. Examples of the host material are not particularly limited, and any metal complex or organic compound can be used as long as the triplet energy of the host is greater than that of the dopant. Any host material can be used with any dopant as long as the triplet criterion is satisfied.

[0252] Examples of metal complexes used as hosts are represented by the following general formula:

Chemical formula

Chemical formula

[0253] In one aspect, the host compound comprises at least one selected from the group consisting of aromatic hydrocarbon cyclic compounds such as benzene, biphenyl, triphenyl, triphenylene, tetraphenylene, naphthalene, anthracene, phenalene, phenanthrene, fluorene, pyrene, chrysene, perylene, and azulene; aromatic heterocyclic compounds such as dibenzothiophene, dibenzofuran, dibenzoselenophene, furan, thiophene, benzofuran, benzothiophene, benzoselenophene, carbazole, indolocarbazole, pyridylindole, 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, phenoxazine, benzofuropyridine, furodipyridine, benzothienopyridine, thienodipyridine, benzoselenophenopyridine, and selenophenodipyridine; and at least one selected from the group consisting of 2 to 10 cyclic structural units which are the same or different types of groups selected from aromatic hydrocarbon cyclic groups and aromatic heterocyclic groups and are directly or via at least one of an oxygen atom, a nitrogen atom, a sulfur atom, a silicon atom, a phosphorus atom, a boron atom, a chain structural unit, and an aliphatic cyclic group and are bonded to each other. Each option within each group may be unsubstituted or substituted by a substituent selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof.

[0254] In one aspect, the host compound has the following groups in the molecule: [Chemical formula] (wherein R 101 is selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof, and when this is aryl or heteroaryl, it has the same definition as Ar above. k is an integer from 0 to 20 or from 1 to 20. X 101 ~X 108 is independently selected from C (including CH) or N. Z 101 and Z 102 are independently selected from NR 101 , O, or S. ) and includes at least one of them.

[0255] Non-limiting examples of host materials that can be used in OLEDs in combination with the materials disclosed in this specification are illustrated below together with the references that disclose those materials: EP2034538, EP2034538A, EP2757608, JP2007254297, KR20100079458, KR20120088644, KR20120129733, KR20130115564, TW201329200, US20030175553, US20050238919, US20060280965, US20090017330, US20090030202, US20090167162, US20090302743, US20090309488, US20100012931, US20100084966, US20100187984, US2010187984, US2012075273, US2012126221, US2013009543, US2013105787, US2013175519, US2014001446, US20140183503, US20140225088, US2014034914, US7154114, WO2001039234, WO2004093207, WO2005014551, WO2005089025, WO2006072002, WO2006114966, WO2007063754, WO2008056746, WO2009003898, WO2009021126, WO2009063833, WO2009066778, WO2009066779, WO2009086028, WO2010056066, WO2010107244, WO2011081423, WO2011081431, WO2011086863, WO2012128298, WO2012133644, WO2012133649, WO2013024872, WO2013035275, WO2013081315, WO2013191404, WO2014142472, US20170263869, US20160163995, US9466803.

Chem.

Chem.

[0256] e) Additional emitter: One or more additional emitter dopants may be used in combination with the compounds of the present disclosure. Examples of additional emitter dopants are not particularly limited, and any compound may be used as long as it is a compound usually used as an emitter material. Examples of suitable emitter materials include, but are not limited to, compounds that can emit light through phosphorescence, fluorescence, thermally activated delayed fluorescence, i.e., TADF (also called E-type delayed fluorescence), triplet-triplet annihilation, or a combination of these processes.

[0257] Non-limiting examples of emitter materials that can be used in OLEDs in combination with the materials disclosed in this specification, references that disclose those materials: CN103694277, CN1696137, EB01238981, EP01239526, EP01961743, EP1239526, EP1244155, EP1642951, EP1647554, EP1841834, EP1841834B, EP2062907, EP2730583, JP2012074444, JP2013110263, JP4478555, KR1020090133652, KR20120032054, KR20130043460, TW201332980, US06699599, US06916554, US20010019782, US20020034656, US20030068526, US20030072964, US20030138657, US20050123788, US20050244673, US2005123791, US2005260449, US20060008670, US20060065890, US20060127696, US20060134459, US20060134462, US20060202194, US20060251923, US20070034863, US20070087321, US20070103060, US20070111026, US20070190359, US20070231600, US2007034863, US2007104979, US2007104980, US2007138437, US2007224450, US2007278936, US20080020237, US20080233410, US20080261076, US20080297033, US200805851, US2008161567, US2008210930, US20090039776, US20090108737, US20090115322, US20090179555, US2009085476, US2009104472, US20100090591, US20100148663, US20100244004, US20100295032, US2010102716, US2010105902, US2010244004, US2010270916, US20110057559,US20110108822, US20110204333, US2011215710, US2011227049, US2011285275, US2012292601, US20130146848, US2013033172, US2013165653, US2013181190, US2013334521, US20140246656, US2014103305, US6303238, US6413656, US6653654, US6670645, US6687266, US6835469, US6921915, US7279704, US7332232, US7378162, US7534505, US7675228, US7728137, US7740957, US7759489, US7951947, US8067099, US8592586, US8871361, WO06081973, WO06121811, WO07018067, WO07108362, WO07115970, WO07115981, WO08035571, WO2002015645, WO2003040257, WO2005019373, WO2006056418, WO2008054584, WO2008078800, WO2008096609, WO2008101842, WO2009000673, WO2009050281, WO2009100991, WO2010028151, WO2010054731, WO2010086089, WO2010118029, WO2011044988, WO2011051404, WO2011107491, WO2012020327, WO2012163471, WO2013094620, WO2013107487, WO2013174471, WO2014007565, WO2014008982, WO2014023377, WO2014024131, WO2014031977, WO2014038456, WO2014112450 are exemplified below., [Chemical formula] [Chemical formula] [Chemical formula] [Chemistry]

[0258] f) HBL: The hole-blocking layer (HBL) can be used to reduce the number of holes and / or excitons emitted from the light-emitting layer. The presence of such a blocking layer in the device can result in significantly higher efficiency and / or longer lifetime compared to a similar device lacking the blocking layer. Also, the blocking layer can be used to limit light emission to a desired region of the OLED. In some embodiments, the HBL material has a lower HOMO (farther from the vacuum level) and / or higher triplet energy than the emitter closest to the HBL interface. In some embodiments, the HBL material has a lower HOMO (farther from the vacuum level) and / or higher triplet energy than one or more of the hosts closest to the HBL interface.

[0259] In one aspect, the compound used in the HBL contains the same molecule or the same functional group as that used as the host described above.

[0260] In another aspect, the compound used in the HBL has the following group in the molecule [Chemistry] (wherein k is an integer from 1 to 20; L 101 is another ligand, and k' is an integer from 1 to 3) and contains at least one of them.

[0261] g) ETL: The electron transport layer (ETL) can include a material capable of transporting electrons. The electron transport layer can be intrinsic (undoped) or can be doped. Doping can be used to enhance conductivity. Examples of ETL materials are not particularly limited, and any metal complex or organic compound can be used as long as it is normally used for transporting electrons.

[0262] In one aspect, the compound used in the ETL has the following groups in the molecule:

Chemical formula

[0263] In another aspect, the metal complex used in the ETL has the following general formula:

Chemical formula

[0264] Non-limiting examples of ETL materials that can be used in OLEDs in combination with the materials disclosed in this specification are exemplified below together with the references that disclose those materials: CN103508940, EP01602648, EP01734038, EP01956007, JP2004-022334, JP2005149918, JP2005-268199, KR0117693, KR20130108183, US20040036077, US20070104977, US2007018155, US20090101870, US20090115316, US20090140637, US20090179554, US2009218940, US2010108990, US2011156017, US2011210320, US2012193612, US2012214993, US2014014925, US2014014927, US20140284580, US6656612, US8415031, WO2003060956, WO2007111263, WO2009148269, WO2010067894, WO2010072300, WO2011074770, WO2011105373, WO2013079217, WO2013145667, WO2013180376, WO2014104499, WO2014104535. [Chemical formula] [Chemical formula]

[0265] h) Charge generation layer (CGL) In tandem or stacked OLEDs, the CGL plays an important role in performance and consists of an n-doped layer and a p-doped layer for electron and hole injection, respectively. Electrons and holes are supplied from the CGL and the electrodes. The consumed electrons and holes in the CGL are replenished by the electrons and holes injected from the cathode and anode, respectively, and then the bipolar current gradually reaches a stable state. Typical CGL materials include n-type and p-type conductive dopants used in the transport layer.

[0266] In any of the above compounds used in each layer of the OLED device, the hydrogen atoms can be partially or fully deuterated. The minimum amount of hydrogen in the deuterated compound is selected from the group consisting of 30%, 40%, 50%, 60%, 70%, 80%, 90%, 95%, 99%, and 100%. Thus, without limitation, any specifically listed substituents such as methyl, phenyl, pyridyl, etc. may be in their non-deuterated, partially deuterated, and fully deuterated versions. Similarly, classes of substituents such as alkyl, aryl, cycloalkyl, heteroaryl, etc., without being limited to these, may also be in their non-deuterated, partially deuterated, and fully deuterated versions.

[0267] It is understood that the various embodiments described herein are merely by way of example and are not intended to limit the scope of the present invention. For example, many of the materials and structures described herein can be replaced with other materials and structures without departing from the spirit of the present invention. Thus, the present invention as claimed may include variations from the specific examples and preferred embodiments described herein, as will be apparent to those skilled in the art. It is understood that the various theories as to why the present invention works are not intended to be limiting.

[0268] E. Experimental Data Synthesis Example Synthesis of 5-neopentyl-1-phenyl-1H-pyrazole:

Chemical Formula

[0269] Synthesis of 4-bromo-5-neopentyl-1-phenyl-1H-pyrazole:

Chemical formula

[0270] Synthesis of 5-neopentyl-1,4-diphenyl-1H-pyrazole:

Chemical formula

[0271] Synthesis of iridium dimer:

Chemical formula

[0272] Synthesis of iridium solvent triflate:

Chemical formula

[0273] Synthesis of representative compounds of the present invention:

Chemical formula

[0274] All related compounds of the present invention can generally be synthesized in the same manner by following the above synthetic method.

[0275] Non-limiting exemplary embodiments:

[0276] The following numbered embodiments are within the scope of the present invention disclosed herein. Exemplary embodiment 1. A compound having a first ligand L A wherein the first ligand L A has the structure of formula I:

Chemical formula

Chemical formula

Chemical Formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical Structure

Chemical Structure

Chemical Structure

Chemical Structure

Chemical Structure

Chem.

Chem.

Chem.

Chem.

Chem.

Chem.

Chem.

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Claims

1. The first ligand L Ａ A compound having the formula: The ligand L Ａ has the structure of Formula I: 【Chemistry 1】 wherein moieties A and B are each independently a monocyclic ring or a polycyclic fused ring system, and each ring of said monocyclic ring or said polycyclic fused ring system is independently a 5-10 membered carbocyclic or heterocyclic ring; Z １ ~Z ４ are each independently C or N; K １ and K. ２ are each independently a direct bond, O, S, N(R α ), P(R α ), B(R α ), C(R α ) (R β ), and Si(R α ) (R β ) selected from the group consisting of; L １ is a direct bond, BR, BRR', NR, PR, P(O)R, O, S, Se, C=O, C=S, C=Se, C=NR', C=CRR', S=O, SO ２ , CR, CRR′, SiRR′, and GeRR′; R Ａ and R Ｂ each independently represent one substitution up to the maximum permitted number of substitutions, or no substitution; Each R, R', R α , R β , R Ａ , and R Ｂ are independently hydrogen or a substituent selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, germyl, boryl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, selenyl, and combinations thereof; L Ａ is coordinated to a metal M; M is coordinated to at least one ancillary ligand; L Ａ can be combined with one or more additional ligands to form a tridentate, tetradentate, pentadentate, or hexadentate ligand; The compound has a perpendicular dipole ratio of 0.33 or greater; At least one of the following statements is true: (1) At least one R Ａ Or R Ｂ contains an electron withdrawing group which is not fluorine; (2) At least one R Ａ Or R Ｂ contains a fluorine atom directly attached to a fused polycyclic ring system; (3) at least one R Ａ Or R Ｂ contains a silyl group or a germyl group; (4) the compound contains at least two metal atoms; (5) The compound is chiral, that is, one enantiomer or diastereomer is present in at least 5% enantiomeric excess; (6) K １ Or K ２ is not a direct bond; and 【Chemistry 2】 But not a compound.

2. The compound has a first constraint vector M that connects any two atoms in the compound and passes within 2 Å of the metal. １ A first free vector F １ and the first constraint vector M １ the length of the second constraint vector M connecting any two atoms in the compound is greater than 18 Å; ２ A second free vector F represented by ２ and the second constraint vector M ２ the length of the transition dipole moment vector defined on said compound is greater than 18 Å; １ and F ２ The compound of claim 1 , which forms an angle of less than 45 degrees with the cross product of

3. The compound has two metal coordinate bonds in a trans configuration; The compound has a first vector W formed between any atom in the periphery of the compound and the metal M. １ having The compound is a second vector W formed between any other atom in the periphery of the compound and the metal M. ２ having The first vector W １ and the second vector W ２ are greater than 9.5 Å in size, respectively; and the transition dipole moment vector of the compound and the first vector W １ and the second vector W ２ 2. The compound of claim 1 , wherein the angle between the cross product of

4. The ligand L Ａ but, 【Chemistry 3】 【Chemistry 4】 【Chemistry 5】 wherein T is selected from the group consisting of B, Al, Ga, and In; E is selected from the group consisting of O, S, Se, and Te; K １’ is a direct bond or NR ｅ , P.R. ｅ , O, S, and Se; Each Y １ ~Y １３ is independently selected from the group consisting of carbon and nitrogen; Y' is BR ｅ , N.R. ｅ , P.R. ｅ , O, S, Se, C=O, S=O, SO ２ , C.R. ｅ R ｆ , SiR ｅ R ｆ , and GeR ｅ R ｆ selected from the group consisting of: R ｅ and R ｆ can be fused or linked to form a ring; Each R ａ , R ｂ , R ｃ , and R ｄ can independently represent from one substitution up to the maximum possible number of substitutions, or no substitution; Each R ａ１ , R ｂ１ , R ｃ１ , R ｄ１ , R ａ , R ｂ , R ｃ , R ｄ , R ｅ , and R ｆ is independently hydrogen or a substituent selected from the group consisting of General Substituents defined herein; and R ａ１ , R ｂ１ , R ｃ１ , R ｄ１ , R ａ , R ｂ , R ｃ , and R ｄ any two adjacent substituents of may be fused or linked to form a ring or to form a multidentate ligand.

5. M (L Ａ ) ｐ (L Ｂ ) ｑ (L Ｃ ) ｒ wherein L Ｂ and L Ｃ are each a bidentate ligand; p is 1, 2, or 3; q is 0, 1, or 2; r is 0, 1, or 2; and p+q+r is the oxidation state of the metal M.

6. Ir(L Ａ ) ３ , Ir(L Ａ ) (L Ｂ ) ２ , Ir(L Ａ ) ２ (L Ｂ ), Ir(L Ａ ) ２ (L Ｃ ), and Ir(L Ａ ) (L Ｂ ) (L Ｃ ) wherein L Ａ , L Ｂ , and L Ｃ The compound according to claim 5 , wherein:

7. At least one R ａ１ , R ｂ１ , R ｃ１ , R ｄ１ , R ａ , R ｂ , R ｃ , R ｄ , R ｅ , or R ｆ The compound of claim 4 , wherein comprises silyl or germyl.

8. L Ａ But, L Ａｉ where i is an integer from 1 to 98; and L Ｂ L Ｂｋ where k is an integer from 1 to 836; The compound has the formula Ir(L Ａｉ ) ３ When the compound has Ir(L Ａ１ ) ３ ~Ir(L Ａ９８ ) ３ selected from the group consisting of: The compound has the formula Ir(L Ａｉ ) (L Ｂｋ ) ２ When the compound has Ir(L Ａ１ ) (L Ｂ１ ) ２ ~Ir(L Ａ９８ ) (L Ｂ８３６ ) ２ selected from the group consisting of: The compound has the formula Ir(L Ａｉ ) ２ (L Ｂｋ ), the compound has Ir(L Ａ１ ) ２ (L Ｂ１ ) to Ir(L Ａ９８ ) ２ (L Ｂ８３６ ) selected from the group consisting of; The compound has the formula Ir(L Ａｉ ) ２ (L Ｃｊ－Ｉ ), the compound has Ir(L Ａ１ ) ２ (L Ｃ１－Ｉ ) to Ir(L Ａ９８ ) ２ (L Ｃ１４１６－Ｉ ) selected from the group consisting of; and The compound has the formula Ir(L Ａｉ ) ２ (L Ｃｊ－ＩＩ ), the compound has Ir(L Ａ１２ (L Ｃ１－ＩＩ ) to Ir(L Ａ９８ ) ２ (L Ｃ１４１６－ＩＩ ) selected from the group consisting of; Each L Ｂｋ is a structure defined as follows: 【Chemistry 6】 【Chemistry 7】 【Chemistry 8】 【Chemistry 9】 【Chemistry 10】 【Chemistry 11】 【Chemistry 12】 【Chemistry 13】 【Chemistry 14】 【Chemistry 15】 【Chemistry 16】 【Chemistry 17】 【Chemistry 18】 【Chemistry 19】 【Chemistry 20】 【Chemistry 21】 【Chemical 22】 【Chemistry 23】 【Chemistry 24】 【Chemistry 25】 【Chemistry 26】 【Chemical 27】 【Chemistry 28】 【Chemical Formula 29】 【Chemistry 30】 【Chemistry 31】 【Chemistry 32】 【Chemical 33】 【Chemical Formula 34】 【Chemistry 35】 【Chemical 36】 【Chemical 37】 【Chemical 38】 【Chemical 39】 【Chemistry 40】 【Chemistry 41】 【Chemistry 42】 【Chemistry 43】 where j is an integer from 1 to 1416, and each L Ｃｊ－Ｉ is the formula 【Chemistry 44】 having a structure based on Each L Ｃｊ－ＩＩ is the formula 【Chemistry 45】 wherein L Ｃｊ－Ｉ and L Ｃｊ－ＩＩ Each L in Ｃｊ About R ２０１ and R ２０２ are each independently one of the following: 【Chemistry 46】 【Chemistry 47】 【Chemistry 48】 【Chemistry 49】 【Chemistry 50】 【Chemistry 51】 【Chemistry 52】 【Chemistry 53】 It is defined as follows: Ｄ１ ~R Ｄ２４６ has the following structure: 【Chemical 54】 【Chemistry 55】 【Chemistry 56】 【Chemistry 57】 7. The compound of claim 6 having the formula:

9. anode; A cathode; and An organic layer disposed between the anode and the cathode. wherein the organic layer comprises a first ligand L Ａ Compounds having the formula: The ligand L Ａ has the structure of Formula I: 【Chemistry 58】 wherein moieties A and B are each independently a monocyclic ring or a polycyclic fused ring system, and each ring of the monocyclic ring or polycyclic fused ring system is independently a 5-10 membered carbocyclic or heterocyclic ring; Z １ ~Z ４ are each independently C or N; K １ and K. ２ are each independently a direct bond, O, S, N(R α ), P(R α ), B(R α ), C(R α ) (R β ), and Si(R α ) (R β ) selected from the group consisting of; L １ is a direct bond, BR, BRR', NR, PR, P(O)R, O, S, Se, C=O, C=S, C=Se, C=NR', C=CRR', S=O, SO ２ , CR, CRR′, SiRR′, and GeRR′; R Ａ and R Ｂ each independently represent one substitution up to the maximum permitted number of substitutions, or no substitution; Each R, R', R α , R β , R Ａ , and R Ｂ are independently hydrogen or a substituent selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, germyl, boryl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, selenyl, and combinations thereof; L Ａ is coordinated to a metal M; M is coordinated to at least one ancillary ligand; L Ａ can be combined with one or more additional ligands to form a tridentate, tetradentate, pentadentate, or hexadentate ligand; The compound has a perpendicular dipole ratio of 0.33 or greater; At least one of the following statements is true: (1) At least one R Ａ Or R Ｂ contains an electron withdrawing group which is not fluorine; (2) At least one R Ａ Or R Ｂ contains a fluorine atom directly attached to a fused polycyclic ring system; (3) at least one R Ａ Or R Ｂ contains a silyl group or a germyl group; (4) the compound contains at least two metal atoms; (5) The compound is chiral, that is, one enantiomer or diastereomer is present in at least 5% enantiomeric excess; (6) K １ Or K ２ is not a direct bond; and The compound is 【Chemistry 59】 Nor is it an organic light emitting device (OLED).

10. anode; A cathode; and An organic layer disposed between the anode and the cathode. wherein the organic layer comprises a first ligand L Ａ Compounds having the formula: The ligand L Ａ has the structure of Formula I: 【Chemistry 60】 wherein moieties A and B are each independently a monocyclic ring or a polycyclic fused ring system, and each ring of the monocyclic ring or polycyclic fused ring system is independently a 5-10 membered carbocyclic or heterocyclic ring; Z １ ~Z ４ are each independently C or N; K １ and K. ２ are each independently a direct bond, O, S, N(R α ), P(R α ), B(R α ), C(R α ) (R β ), and Si(R α ) (R β ) selected from the group consisting of; L １ is a direct bond, BR, BRR', NR, PR, P(O)R, O, S, Se, C=O, C=S, C=Se, C=NR', C=CRR', S=O, SO ２ , CR, CRR′, SiRR′, and GeRR′; R Ａ and R Ｂ each independently represent one substitution up to the maximum permitted number of substitutions, or no substitution; Each R, R', R α , R β , R Ａ , and R Ｂ are independently hydrogen or a substituent selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, germyl, boryl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, selenyl, and combinations thereof; L Ａ is coordinated to a metal M; M is coordinated to at least one ancillary ligand; L Ａ can be combined with one or more additional ligands to form a tridentate, tetradentate, pentadentate, or hexadentate ligand; The compound has a perpendicular dipole ratio of 0.33 or greater; At least one of the following statements is true: (1) At least one R Ａ Or R Ｂ contains an electron withdrawing group which is not fluorine; (2) At least one R Ａ Or R Ｂ contains a fluorine atom directly attached to a fused polycyclic ring system; (3) at least one R Ａ Or R Ｂ contains a silyl group or a germyl group; (4) the compound contains at least two metal atoms; (5) The compound is chiral, that is, one enantiomer or diastereomer is present in at least 5% enantiomeric excess; (6) K １ Or K ２ is not a direct bond; and The compound is 【Chemistry 61】 But not. The consumer product is one of a flat panel display, a computer monitor, a medical monitor, a television, a billboard, a light for indoor or outdoor illumination and / or signaling, a head-up display, a fully or partially transparent display, a flexible display, a laser printer, a telephone, a mobile phone, a tablet, a phablet, a personal digital assistant (PDA), a wearable device, a laptop computer, a digital camera, a camcorder, a viewfinder, a microdisplay less than 2 inches diagonal, a 3-D display, a virtual reality or augmented reality display, a vehicle, a video wall including multiple displays aligned together, a theater or stadium screen, a light therapy device, and a signage.

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