The present disclosure relates to an organic electroluminescent device comprising an anode, a cathode, and an organic layer between the anode and the cathode, wherein the organic layer comprises one or more light-emitting layers; and at least one light-emitting layer comprises one or more dopant compounds and two or more host compounds. The organic electroluminescent device of the present disclosure has low driving voltage, high color purity, high luminous efficiency, and a long lifespan.

Tridentate platinum, palladium, and gold complexes of Formulas A-I and A-II and tridentate iridium and rhodium compounds of Formulas B-I, B-II, and B-III suitable for delayed fluorescent and phosphorescent or phosphorescent emitters in display and lighting applications.

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The present disclosure relates to compounds capable of emitting delayed fluorescence, and uses of these compounds in organic light-emitting diodes.

The present invention provides a luminescent film containing at least a phosphorescent compound and a fluorescent compound, wherein the convolution integral value J of the emission spectrum of the phosphorescent compound and the absorption spectrum of the fluorescent compound satisfies equation (1), the light emission from the fluorescent compound accounts for at least 90% of the emission spectrum of the luminescent film, and the absolute photoluminescence quantum efficiency (PLQE) of the luminescent film is represented by equation (2). Equation (1): J≥1.5×10.sup.14, Equation (2): PLQE (a film composed of a phosphorescent compound and a host compound)×0.9≤PLQE (a film containing a phosphorescent compound and a fluorescent compound) [The lowest triplet excited state of the host compound is higher than the lowest triplet excited state of the phosphorescent compound, and does not suppress the luminescent property of the phosphorescent compound.]

The near-infrared window of fluorescent heptamethine cyanine dyes greatly facilitates biological imaging because there is deep penetration of the light and negligible background fluorescence. But dye instability, aggregation, and poor pharmacokinetics are current drawbacks that limit performance and the scope of possible applications. All these limitations are simultaneously overcome with a new molecular design strategy that produces a charge balanced and sterically shielded fluorochrome. The key design feature is a meso-Aryl group that simultaneously projects two shielding arms directly over each face of a linear heptamethine polyene. Cell and mouse imaging experiments compared a shielded heptamethine cyanine dye (and several peptide and antibody bioconjugates) to benchmark heptamethine dyes and found that the shielded systems possess an unsurpassed combination of photophysical, physiochemical and biodistribution properties that greatly enhance bioimaging performance.

A light emitting element that includes a first electrode, a second electrode on the first electrode, and at least one functional layer between the first electrode and the second electrode is provided. The at least one functional layer includes a polycyclic compound represented by a specific chemical structure, and has a high efficiency and low driving voltage properties.

According to an aspect of the present disclosure, a compound having a metal planar tetradentate coordination configuration is disclosed. In the compounds, the metal M is Pt or Pd; the four coordinating atoms are Z.sup.1, Z.sup.2, Z.sup.3, and Z.sup.4 and are each selected from N, C, and O. The compound includes a substituent R, and atoms M, Z.sup.1, Z.sup.2, Z.sup.3, and Z.sup.4 are used to define a first plane that passes through the metal M and is positioned to have a minimum sum of shortest distances with Z.sup.1, Z.sup.2, Z.sup.3, and Z.sup.4. At least one non-hydrogen atom in R falls within a distal circle of a cylinder extending perpendicular to the first plane, where the distal circle of the cylinder is a height h from the base circle and the height h ranges from 3.3 Å to 4.8 Å.

The invention relates to an organic molecule, in particular for use in organic optoelectronic devices. According to the invention, the organic molecule has one first chemical moiety with a structure of formula I, ##STR00001## and one second chemical moiety with a structure of formula II, ##STR00002## wherein the first chemical moiety is linked to the second chemical moiety via a single bond.

The present invention relates to heteroleptic carbene complexes comprising at least two different carbene ligands, to a process for preparing the heteroleptic carbene complexes, to the use of the heteroleptic carbene complexes in organic light-emitting diodes, to organic light-emitting diodes comprising at least one inventive heteroleptic carbene complex, to a light-emitting layer comprising at least one inventive heteroleptic carbene complex, to organic light-emitting diodes comprising at least one inventive light-emitting layer, and to devices which comprise at least one inventive organic light-emitting diode.

The present invention relates to spiro compounds containing electron-conducting groups and to electronic devices, in particular organic electroluminescent devices, comprising these compounds.