The invention provides highly fluorescent materials comprising a heterocyclic systems represented by formula (I): ##STR00001##
wherein i is 0 and Het is ##STR00002##
wherein X is selected from the group consisting of N(A.sub.0)-. The chromophores are particularly useful for absorption and emission of photons in the visible and near infrared wavelength range. The photo-stable highly luminescent chromophores are useful in various applications, including in wavelength conversion films. Wavelength conversion films have the potential to significantly enhance the solar harvesting efficiency of photovoltaic or solar cell devices.

A composition formed of a mixture of two compounds having similar thermal evaporation properties that are pre-mixed into an evaporation source that can be used to co-evaporate the two compounds into an emission layer in OLEDs via vacuum thermal evaporation process is disclosed. The first and second compounds can have an evaporation temperature T.sub.1 and T.sub.2, respectively, of 150 to 350 C., and the absolute value of T.sub.1-T.sub.2 can be less than 20 C. The first compound can have a concentration C.sub.1 in the mixture and a concentration C.sub.2 in a film formed by evaporating the mixture in a vacuum deposition tool at a constant pressure between 110.sup.6 Torr to 110.sup.9 Torr, at a 2 /sec deposition rate on a surface positioned at a predefined distance away from the mixture being evaporated, where the absolute value of (C.sub.1C.sub.2)/C.sub.1 is less than 5%.

To provide a light-emitting element which emits light in a near-infrared range and has high efficiency and long life, and a light-emitting device, an authentication device, and an electronic apparatus, each of which includes this light-emitting element. A light-emitting element 1 of the invention includes an anode 3, a cathode 8, a light-emitting layer 5 which is provided between the anode 3 and the cathode 8 and emits light in a wavelength range of 700 nm or more by applying a current between the anode 3 and the cathode 8, and an electron transport layer 6 which is provided between the light-emitting layer 5 and the cathode 8, and includes a first electron transport layer 6b located on the cathode 8 side and a second electron transport layer 6a located on the light-emitting layer 5 side, wherein the first electron transport layer 6b contains a first anthracene-based compound, which has an anthracene skeleton and a nitrogen-containing heterocyclic skeleton, and has an average thickness of less than 8 nm, and the second electron transport layer 6a contains a second anthracene-based compound, which has an anthracene skeleton but does not have a heterocyclic skeleton.

Described herein are wavelength conversion films which utilize photostable organic chromophores. In some embodiments, wavelength conversion films and chromophores exhibit improved photostability. In some embodiments, a wavelength conversion film comprising luminescent compounds is useful for improving the solar harvesting efficiency of solar cells, solar panels, or photovoltaic devices. In some embodiments, a wavelength conversion film comprising multiple luminescent compounds is useful for greenhouse roofs. Some embodiments provide an improved solar light wavelength profile for improved plant nutrition and/or growth.

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 relates to an organometallic compound having the structure of Chemical Formula 1, Ir(L.sub.A).sub.m(L.sub.B).sub.n, an organic light emitting diode (OLED) where the organometallic compound is applied to an emitting material layer and an organic light emitting device. The luminous efficiency, color purity and luminous lifespan of the OLED and the organic light emitting device can be improved.

Specifically substituted aza-dibenzofurans and aza-dibenzothiophenes of formula (I) and their use in electronic devices, especially electroluminescent devices. When used as charge transport material, charge blocker material and/or host material in electroluminescent devices, the specifically substituted aza-dibenzofurans and aza-dibenzothiophenes may provide improved efficiency, stability, manufacturability, or spectral characteristics of electroluminescent devices and reduced driving voltage of electroluminescent devices. In formula (I) Y is S or O; one of X.sup.1-X.sup.8 is N; another X.sup.1-X.sup.8 is C-L(R.sup.9)-[X.sup.9X.sup.10X.sup.11]Ring; and the remaining X.sup.1-X.sup.8 are CR.sup.1CR.sup.8 wherein R.sup.1-R.sup.8 are independently H, alkyl, alkenyl, aryl, etc.

##STR00001##

A composition formed of a mixture of two compounds having similar thermal evaporation properties that are pre-mixed into an evaporation source that can be used to co-evaporate the two compounds into an emission layer in OLEDs via vacuum thermal evaporation process is disclosed. The first and second compounds can have an evaporation temperature T.sub.1 and T.sub.2, respectively, of 150 to 350 C., and the absolute value of T.sub.1T.sub.2 can be less than 20 C. The first compound can have a concentration C.sub.1 in the mixture and a concentration C.sub.2 in a film formed by evaporating the mixture in a vacuum deposition tool at a constant pressure between 110.sup.6 Torr to 110.sup.9 Torr, at a 2 /sec deposition rate on a surface positioned at a predefined distance away from the mixture being evaporated, where the absolute value of (C.sub.1C.sub.2)/C.sub.1 is less than 5%.

Novel phosphorescent metal complexes containing ligands having the Formula I:

##STR00001##

bearing either a naphthalene or other fused heterocycle moieties such as benzofuran and benzothiophene useful as emitters in OLEDs and improve the device efficiency and the FWHM of the emission are disclosed.

The present disclosure provides a new series of compounds exhibiting high fluorescence quantum yields in the solid state. In one embodiment, the compounds include a series of 2,3,4,5-tetraphenylgermoles with the same or different 1,1-substituents. In another embodiment, substituted germafluorenes, germa-fluoresceins/rhodamines, and germapins are described. These germanium heterocycles possess ideal photophysical and thermostability properties, which makes them excellent candidates for chemical or biological sensors, host materials for electroluminescent devices and solar cells, and emissive and/or electron-transport layer components in organic light emitting diode devices.