Embodiments provide an organometallic compound, a light-emitting device including the organometallic compound, and an electronic apparatus including the light-emitting device. The light-emitting device includes a first electrode, a second electrode facing the first electrode, an interlayer between the first electrode and the second electrode and including an emission layer, and the organometallic compound, which is represented by Formula 1.

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The description of Formula 1 is provided in the specification.

A light-emitting device includes an electron transport region including a first electron transport layer and a second electron transport layer. The first electron transport layer includes a first compound, the second electron transport layer includes a second compound, the first compound includes a pyrimidine group, the second compound includes a triazine group, and an absolute value of a lowest unoccupied molecular orbital (LUMO) energy of the first compound (E.sub.LUMO_E1) is less than an absolute value of a LUMO energy of the second compound (E.sub.LUMO_E2). An electronic apparatus including the light-emitting device.

Provided is an organic electroluminescent device. The organic electroluminescent device is a blue delayed fluorescent device including an anode, a cathode, an emissive layer disposed between the anode and the cathode and a hole blocking layer disposed between the emissive layer and the cathode, where the hole blocking layer comprises a hole blocking material having a structure of Formula 1, and the emissive layer comprises a first host material, a second host material and a blue delayed fluorescent material having a structure of Formula 3. The blue delayed fluorescent device exhibits excellent overall device performance, such as higher efficiency and longer lifetime. Further provided are a light-emitting device comprising a blue delayed fluorescent unit, a green phosphorescent unit and a red phosphorescent unit and a display assembly comprising the blue delayed fluorescent device and the light-emitting device.

Provided are organometallic compounds having a structure of

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Also provided are formulations that include these organometallic compounds. Further provided are OLEDs and related consumer products that utilize these organometallic compounds.

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.

Disclosed is a device that includes an emissive material or region including a host that is doped with a first material as an emitter that is an acceptor and a phosphorescent-capable second material as a sensitizer. The first material and the second material each has a first singlet state and a first triplet state. The first triplet state of the second material is not lower than the first triplet state of the first material. The second material transfers excitons to the first material and the excitons that transition to the first triplet state of the first material can be activated to the first singlet state of the first material through a thermal activation process.

An organic light-emitting device including a first electrode; a second electrode facing the first electrode; an emission layer between the first electrode and the second electrode; a hole transport region between the first electrode and the emission layer; and an electron transport region between the emission layer and the second electrode, wherein: the emission layer includes a first compound, at least one of the hole transport region and the electron transport region includes a second compound, the first compound is represented by Formula 1A or 1B, and the second compound is represented by Formula 2A or 2B: ##STR00001##

The present invention relates to an organic electronic device comprising at least one inverse coordination complex, the N inverse coordination complex comprising: (i) a core consisting of one atom or of a plurality of atoms forming together a covalent cluster; (ii) a first coordination sphere consisting of at least four electropositive atoms having each individually an electronegativity according to Allen of less than 2,4; and (iii) a second coordination sphere comprising a plurality of ligands; wherein the first coordination sphere is closer to the core than the second coordination sphere; and all atoms of the core have a higher electronegativity according to Allen than any of the electropositive atoms of the first coordination sphere and a method for preparing the same.

A compound and an organic optoelectronic device, the compound being represented by Chemical Formula 1-3a-I or Chemical Formula 1-4a-I: ##STR00001##

An organic light-emitting device including a first electrode, a second electrode, an emission layer disposed between the first electrode and the second electrode, a hole transport region disposed between the first electrode and the emission layer, and an electron transport region disposed between the emission layer and the second electrode, wherein the emission layer includes a host and a dopant, wherein the dopant is an iridium-free organometallic compound, and wherein a dopant concentration profile of the emission layer satisfies predetermined parameters disclosed in the specification.