A light-emitting element includes an anode, a cathode, a light-emitting layer which is provided between the anode and the cathode and emits light in a wavelength range of 700 nm or more by conducting electricity between the anode and the cathode, and an electron transport layer which is provided between the light-emitting layer and the cathode, and includes a first electron transport layer located on the cathode side and a second electron transport layer located on the light-emitting layer side, wherein organic materials contained in the light-emitting layer, a hole injection layer, the first electron transport layer, and the second electron transport layer have a glass transition temperature Tg of 135 C. or higher or do not have a glass transition temperature.

A phosphorescent emitter or delayed fluorescent and phosphorescent emitters represented by Formula 1 or Formula II, where M is platinum or palladium. ##STR00001##

Described herein are molecules for use in organic light emitting diodes. Example molecules comprise at least one moiety A and at least one moiety D. Values and preferred values of the moieties A and D are described herein. The molecules comprise at least one atom selected from Si, Se, Ge, Sn, P, or As.

Compounds comprising phosphorescent metal complexes comprising cyclometallated imidazo[1,2-f]phenanthridine and diimidazo[1,2-a:1,2-c]quinazoline ligands, or isoelectronic or benzannulated analogs thereof, are described. Organic light emitting diode devices comprising these compounds are also described.

The present disclosure provides a nitrogen-containing heterocyclic compound having general formula (I) and an organic photoelectric apparatus thereof. ##STR00001## where A.sub.1, A.sub.2, A.sub.3, A.sub.4, A.sub.5, A.sub.6, A.sub.7, and A.sub.8 are independently selected from a hydrogen atom, at least one compound having the general formula (II) and at least one compound having the general formula (III), ##STR00002## where Y.sub.1, Y.sub.2, and Y.sub.3 are independently selected from C and N; R.sub.3 and R.sub.4 are independently selected from C.sub.6-30 aromatic group and C.sub.2-30 heterocyclic aromatic group, ##STR00003## wherein X is selected from any one of oxyl group (O), sulfhydryl group (S), substituted or non-substituted imino group, substituted or non-substituted methylene group, and substituted or non-substituted silicylene group; R.sub.5, R.sub.6, R.sub.7, R.sub.8, R.sub.9, R.sub.10, R.sub.11, and R.sub.12 are independently selected from hydrogen, deuterium, C.sub.1-30 alkyl group, C.sub.6-30 aromatic group, or C.sub.2-30 heterocyclic aromatic group.

Compounds comprising phosphorescent metal complexes comprising cyclometallated imidazo[1,2-f]phenanthridine and diimidazo[1,2-a:1,2-c]quinazoline ligands, or isoelectronic or benzannulated analogs thereof, are described. Organic light emitting diode devices comprising these compounds are also described.

Compounds comprising phosphorescent metal complexes comprising cyclometallated imidazo[1,2-f]phenanthridine and diimidazo[1,2-a:1,2-c]quinazoline ligands, or isoelectronic or benzannulated analogs thereof, are described. Organic light emitting diode devices comprising these compounds are also described.

Compounds comprising phosphorescent metal complexes comprising cyclometallated imidazo[1,2-f]phenanthridine and diimidazo[1,2-a:1,2-c]quinazoline ligands, or isoelectronic or benzannulated analogs thereof, are described. Organic light emitting diode devices comprising these compounds are also described.

Provided are an organic EL device which is practically satisfactory in terms of a light-emitting characteristic, a driving voltage, and durability, and a compound for organic EL devices to be used in the device. The organic EL device is an organic EL device produced by laminating, on a substrate, an anode, a plurality of organic layers including a light-emitting layer, and a cathode, the organic EL device containing, in at least one organic layer selected from the light-emitting layer, a hole-transporting layer, an electron-transporting layer, a hole-blocking layer, and an electron-blocking layer, a boron compound having two indolocarbazolyl groups in a molecule thereof. The boron compound is represented by Y-L-B(A)a-L-Y or Y-L(Z)b-Y, where Y represents an indolocarbazolyl group, L represents an aromatic group, and Z represents a boron-containing group.

Provided are a compound of Formula 1 and an organic electric element including a first electrode, a second electrode, and an organic material layer between the first and the second electrodes, where the organic material layer contains the compound of Formula 1 and improves luminous efficiency, stability, and life span of the element.