The present disclosure provides coinage metal carbene emitters of Formula I; organic light emitting device (OLED) comprising an anode, a cathode, and an organic layer, disposed between the anode and the cathode, comprising a compound of Formula I; and consumer products comprising an OLED comprising a compound of Formula I:

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The present invention relates to a an organic electroluminescent device comprising at least one light-emitting layer B comprising at least one host material H.sup.B, at least one thermally activated delayed fluorescence (TADF) material E.sup.B, and at least one small full width at half maximum (FWHM) emitter S.sup.B wherein E.sup.B transfers energy to S.sup.B and S.sup.B emits light with an emission maximum in the wavelength range from 500 nm to 560 nm.

The present invention provides nanostructure compositions and methods of producing nanostructure compositions. The nanostructure compositions comprise a population of nanostructures comprising donor-acceptor ligands. The present invention also provides nanostructure films comprising the nanostructure compositions and methods of making nanostructure films using the nanostructure compositions.

An organic EL device includes: an anode, a cathode, and an emitting layer, in which the emitting layer contains a first compound of a formula (1), a second compound of a formula (2), and a third compound that exhibits delayed fluorescence, and singlet energies S.sub.1 of the first compound, the second compound, and the third compound satisfy Numerical Formula 1 and Numerical Formula 2.

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In the formula (1), A represents a group of a formula (a1) or the like, L represents a linking group or the like, and B represents an aryl group or the like. The first compound of the formula (1) has no carbonyl group. In the formula (2), Y.sub.21 to Y.sub.26 each independently represent an N atom, CR.sub.A, or the like. R.sub.A represents a substituent, a group of a formula (2A), or the like.

A thermally activated delayed fluorescent molecular material, a method for synthesizing the same, and an organic electroluminescent device are provided. The thermally activated delayed fluorescent molecular material includes an electron donor and an electron acceptor containing an indenyl group. A phenyl group in diphenylamine or triphenylamine in a donor molecule is replaced with an indenyl group, so that the electron-donating ability of the donor is increased, and the non-radiative transition rate is effectively suppressed, thereby increasing the photoluminescence quantum yield (PLQY) of the molecule. Further, the torsion angle between the electron donor and the electron acceptor is also increased, while the electron cloud overlap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) is reduced, thereby obtaining a smaller ΔE.sub.ST value.

The invention relates to an organic electroluminescent device comprising a light-emitting layer B comprising a host material H.sup.B, a thermally activated delayed fluorescence (TADF) material E.sup.B, and a depopulation agent S.sup.B.

A series of novel donor-acceptor type TADF luminogens have been designed with the aim of developing stable OLEDs with enhanced operational stability and improved color purity. These materials could be found utilization for full color displays and lighting applications.

Provided are an organic electroluminescent device, a display panel, and a display apparatus. An exciton layer adjacent to a light-emitting layer is added, and the exciton layer serves as an exciton recombination region and achieves the effect of increasing the density of excitons, where the singlet-state energy level of the exciton layer is higher than the singlet-state energy level of a host material in the light-emitting layer, and an emission spectrum of the exciton layer and an absorption spectrum of the host material in the light-emitting layer have an overlapping area. Moreover, the exciton layer allows triplet-state excitons formed in the exciton layer to form singlet-state excitons via a reverse intersystem crossing process.

Provided is an organic light-emitting device including a first electrode; a second electrode; and an organic layer between the first electrode and the second electrode and comprising an emission layer, wherein the organic layer includes at least one condensed cyclic compound represented by Formula 1.

An organic electroluminescence device includes a first electrode, a second electrode facing the first electrode, and a plurality of organic layers disposed between the first electrode and the second electrode. At least one organic layer includes a fused polycyclic compound represented by Formula 1, thereby exhibiting improved luminous efficiency.