A light emitting photonic crystal having an organic light emitting diode and methods of making the same are disclosed. An organic light emitting diode disposed within a photonic structure having a band-gap, or stop-band, allows the photonic structure to emit light at wavelengths occurring at the edges of the band-gap. Photonic crystal structures that provide this function may include materials having a refractive index that varies.

A compound having a structure of ##STR00001##
is disclosed. In these formulas, each R.sub.1, R.sub.2, and R.sub.3 is independently selected from hydrogen, alkyl, and aryl; at least one of R.sub.1 and R.sub.2 is a branched alkyl containing at least 4 carbon atoms, where the branching occurs at a position further than the benzylic position; where R.sub.1 and R.sub.3 are mono-, di-, tri-, tetra-, or no substitutions; and R.sub.2 is mono-, di-, or no substitutions. Heteroleptic iridium complexes including such compounds, and devices including such compounds are also disclosed.

An organometallic compound represented by Formula 1:

##STR00001## wherein, in Formula 1, groups and variables are the same as described in the specification.

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.

Compounds containing indolocarbazole compounds of Formula I or Formula II comprising terphenyl groups and compounds of Formula III comprising triazine groups are disclosed in this application. These compounds are useful for application in organic electroluminescent devices. ##STR00001##

A novel compound having a first ligand L.sub.A of

##STR00001##

is disclosed. The compound is useful as emitter dopant in OLEDs.

The present invention relates to indane derivatives of the formula (I) and mixtures thereof, wherein X is selected from groups of the formula -A-(NAr.sub.2), wherein A is a chemical bond or phenylene which is unsubstituted or substituted by 1, 2 or 3 substituents selected from C.sub.1-C.sub.6-alkyl and C.sub.1-C.sub.6-alkoxy; Ar is unsubstituted or substituted aryl, wherein two groups Ar bound to the same nitrogen atom may together with the nitrogen atom also form a fused ring system having 3 or more than 3 unsubstituted or substituted rings; and the variables Y, n, m, k and l are as defined in the claims and the description. The invention further relates to methods for preparing such compounds and their use in organic electronics, in particular as hole transport material or electron blocking material. ##STR00001##

The present disclosure relates to an organic electroluminescent compound and an organic electroluminescent device comprising the same. By comprising the organic electroluminescent compound of the present disclosure, an organic electroluminescent device having low driving voltage, high luminous efficiency, and/or excellent lifespan characteristics can be provided.

A novel organic compound is provided. That is, a novel organic compound that is effective in improving reliability of a light-emitting element is provided. The organic compound includes a condensed ring including a pyrimidine ring and is represented by General Formula (G1). In General Formula (G1), A represents a group having 6 to 100 carbon atoms and includes at least one of an aromatic ring and a heteroaromatic ring. The aromatic ring and the heteroaromatic ring may each include a substituent. Furthermore, Q represents oxygen or sulfur. A ring X represents a substituted or unsubstituted naphthalene ring or a substituted or unsubstituted phenanthrene ring.

The present invention includes novel platinum complexes with tridentate ligands forming dimeric structures that are calculated to have blue emission. The ligand backbone and pendant donor rings can be altered to give different emission maxima. The present invention also includes various pendant donor rings and multiple different ligand backbones. Such complexes are suitable for use as an emitter in organic light emitting devices.