The present invention relates to a device containing an organometal-complex luminescent material. The device comprises a luminescent layer. The luminescent layer contains an organometal complex which has a structural formula (I), wherein A, B and C refer to substituted or unsubstituted C, N, O and S atoms independently; a dashed ring for linkage between A and B atoms refers to a substituted or unsubstituted conjugated ring structure; L1, L2, L3 and L4 are single bonds or double bonds independently, wherein L3 and L4 are part of the conjugated ring structure for linkage between A and B atoms; X, X1, Y and Y1 are C, N, O and S atoms independently; Ar1 and Ar2 are substituted or unsubstituted conjugated ring structures independently; M refers to Pt, W and Au atoms. An organometal complex in the luminescent material is high in fluorescence quantum efficiency and heat stability and low in quenching constant and can be used for manufacturing high-efficiency and low-efficiency roll-off red-light OLEDs. ##STR00001##

Imidazophenanthridine ligands and metal complexes are provided. The compounds exhibit improved stability through a linking substitution that links a nitrogen bonded carbon of an imidizole ring to a carbon on the adjacent fused aryl ring. The compounds may be used in OLEDs, particularly as emissive dopants in the emissive region in the OLEDs, providing devices with improved efficiency, stability, and manufacturing. In particular, the compounds provided herein may be used in blue devices having high efficiency.

Provided are a compound of Formula 1; an organic electric element comprising a first electrode, a second electrode, and an organic material layer formed between the first electrode and the second electrode, comprising a mixture of a compound of Formula 1 and a compound of Formula 2, or comprising a compound of Formula 3, a subgenus of Formula 1, in the organic material layer; and an electronic device comprising the element, which has lowered driving voltage and increased luminous efficiency and life time.

A compound of Formula I ##STR00001## wherein X.sup.1, X.sup.2, X.sup.3, and X.sup.4 are independently selected from the group consisting of CR.sup.A and N; X.sup.5, X.sup.6, X.sup.7, and X.sup.8 are independently selected from the group consisting of CR.sup.B and N; Y is selected from the group consisting of NR.sup.2, O, S, CR.sup.3R.sup.4, SiR.sup.3R.sup.4 and GeR.sup.3R.sup.4; Z is selected from the group consisting of B, SiR.sup.5, and GeR.sup.6;
wherein R.sup.A and R.sup.B represent mono to the maximum allowable substitution, or no substitution; and R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6 and R.sup.7 are independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, silyl, aryl, heteroaryl, acyl, nitrile, and combinations thereof. The compounds of Formula I will have at least one of R.sup.A, R.sup.B, R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5 and R.sup.6 that comprises a structure selected from the group consisting of: ##STR00002## wherein X is selected from the group consisting of NR.sup.7, O, S and Se; and X.sup.9-X.sup.41 are each independently selected from the group consisting of C and N; and at least one of X.sup.34-X.sup.41 is N. We also describe an OLED comprising an organic layer that includes a compound of Formula I and a consumer product that includes the OLED.

Provided are a compounds comprising a first ligand L.sub.A of ##STR00001##

An organic compound is represented by formula (1). In the formula (1), R.sub.1 to R.sub.24 are each independently selected from the group consisting of a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted amino group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a substituted or unsubstituted aryloxy group, a silyl group, and a cyano group. ##STR00001##

Provided is a light-emitting element with high external quantum efficiency and a low drive voltage. The light-emitting element includes a light-emitting layer which contains a phosphorescent compound and a material exhibiting thermally activated delayed fluorescence between a pair of electrodes, wherein a peak of a fluorescence spectrum and/or a peak of a phosphorescence spectrum of the material exhibiting thermally activated delayed fluorescence overlap(s) with a lowest-energy-side absorption band in an absorption spectrum of the phosphorescent compound, and wherein the phosphorescent compound exhibits phosphorescence in the light-emitting layer by voltage application between the pair of electrodes.

To increase emission efficiency of a fluorescent light-emitting element by efficiently utilizing a triplet exciton generated in a light-emitting layer. The light-emitting layer of the light-emitting element includes at least a host material and a guest material. The triplet exciton generated from the host material in the light-emitting layer is changed to a singlet exciton by triplet-triplet annihilation (TTA). The guest material (fluorescent dopant) is made to emit light by energy transfer from the singlet exciton. Thus, the emission efficiency of the light-emitting element is improved.

Provided is a light-emitting element including a fluorescence-emitting material with high emission efficiency. The light-emitting element includes a pair of electrodes and an EL layer between the pair of electrodes. The EL layer includes a first organic compound, a second organic compound, and a guest material. The first organic compound has a function of emitting a thermally activated delayed fluorescence at room temperature. The guest material has a function of emitting fluorescence. A HOMO level of the first organic compound higher than or equal to a HOMO level of the second organic compound. A LUMO level of the first organic compound is lower than or equal to a LUMO level of the second organic compound.

A light-emitting element including a fluorescent material as a light-emitting material and having high emission efficiency is provided. The light-emitting element includes a pair of electrodes and an EL layer provided between the pair of electrodes. The EL layer includes a host material and a guest material. The host material is capable of exhibiting thermally activated delayed fluorescence at room temperature. The guest material is capable of exhibiting fluorescence. The second triplet excitation energy level of the guest material is higher than or equal to the lowest singlet excitation energy level of the guest material.