Metal complexes with cyclic ligands having Formula (I), ##STR00001##
are disclosed. Ligands with cyclic structure are believed to be beneficial to the rigidity and stability of the metal complexes, which is desirable for improving OLED device performance.

An organic light-emitting device includes a first electrode, a second electrode facing the first electrode, an emission layer between the first electrode and the second electrode, and a hole transport region between the first electrode and the emission layer. The emission layer includes a first compound represented by Formula 1, and the hole transport region includes a second compound represented by Formula 2: ##STR00001##

Provided is a light-emitting device and an electronic apparatus including the same. 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 a capping layer, wherein the emission layer includes a first emitter, the first emitter emits a first light having a first emission spectrum, the capping layer is in a path along which the first light travels, an emission peak wavelength of the first light is about 520 nm to about 550 nm, the first emitter includes platinum, the capping layer includes an amine-containing compound, and a value of a ratio of CIEy to reflective index (RCR value) of the first light extracted to the outside through the capping layer is 38 or less, and the RCR value is calculated according to Equation 1.

CIEy/R(cap)×100  Equation 1

A light-emitting device and an electronic apparatus including the same are provided. 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 a capping layer. The emission layer includes a first emitter, the first emitter emits a first light having a first emission spectrum, the capping layer is in a path on which the first light travels, an emission peak wavelength of the first light is about 510 nm to about 550 nm. The first emitter includes platinum, the capping layer includes an amine-free compound, and a value of a ratio of CIEy to a reflective index (RCR value) of the first light extracted to the outside through the capping layer is 38 or less, and the RCR value is calculated according to CIEy/R(cap)×100.

An organometallic compound is represented by Formula 1. A light-emitting device includes a first electrode, a second electrode facing the first electrode, and an interlayer between the first electrode and the second electrode and including an emission layer, wherein the emission layer includes the organometallic compound. An electronic apparatus including the light-emitting device:

##STR00001##

The description of Formula 1 is the same as in the specification.

A light-emitting device including an organometallic compound represented by Formula 1, an electronic apparatus including the light-emitting device, and the organometallic compound represented by Formula 1 are provided.

##STR00001##

Provided are a light-emitting device and an electronic apparatus including the same. The light-emitting device includes a first electrode, a second electrode facing the first electrode, and an interlayer between the first electrode and the second electrode. The interlayer includes an emission layer, and a hole transport region between the first electrode and the emission layer. The emission layer includes a transition metal-containing organometallic compound. The hole transport region includes an electron-blocking layer. The electron-blocking layer includes a first electron-blocking material and a second electron-blocking material, and the first electron-blocking material and the second electron-blocking material have different hole mobilities.

A light-emitting device includes: a first electrode; a second electrode facing the first electrode; and an interlayer between the first electrode and the second electrode and including an emission layer, wherein the emission layer includes at least one organometallic compound represented by Formula 1:

##STR00001##

wherein Formula 1 is the same as described herein.

A light-emitting device includes an organometallic compound represented by Formula 1, an electronic apparatus including the light-emitting device, and the organometallic compound represented by Formula 1 are provided:

##STR00001##

wherein substituents of Formula 1 are the same as described in the present specification.

A light-emitting device includes a first electrode, a second electrode facing the first electrode, and an interlayer between the first electrode and the second electrode. The interlayer includes an emission layer and a hole transport layer between the first electrode and the emission layer. The emission layer includes a first host, a second host, and a dopant, wherein the first host includes a hole-transporting host, and the second host includes an electron-transporting host or a bipolar host. The hole transport layer includes multiple hole transport layers, the hole transport layers each include a carbazole-based compound, and highest occupied molecular orbital (HOMO) energy levels of the carbazole-based compounds respectively included in neighboring ones of the hole transport layers are different from each other.