Abstract: A novel organometallic complex is provided. The organometallic complex is represented by General Formula (G1). In the organometallic complex represented by General Formula (G1), each of R1, R13, and R14 independently represents an alkyl group that has 1 to 6 carbon atoms and includes deuterium, each of R2 to R12 independently represents hydrogen (including deuterium) or an alkyl group that has 1 to 6 carbon atoms and includes deuterium, each of R15 to R21 independently represents hydrogen (including deuterium), and n represents 1 or 2.

Abstract: A light-emitting device having favorable characteristics is provided. The light-emitting device includes a first electrode, a second electrode, an intermediate layer positioned between the first and second electrodes, a first light-emitting layer, a second light-emitting layer, a first electron-transport layer, and a second electron-transport layer.

Abstract: A light-emitting device having favorable characteristics is provided. The light-emitting device includes a first electrode, a second electrode, an intermediate layer therebetween, a first light-emitting layer, a second light-emitting layer, a first electron-transport layer, and a second electron-transport layer. The first light-emitting layer is between the first electrode and the intermediate layer. The second light-emitting layer is between the intermediate layer and the second electrode. The first electron-transport layer is between the first light-emitting layer and the intermediate layer. The second electron-transport layer is between the second light-emitting layer and the second electrode. The second electron-transport layer has a stacked-layer structure. The intermediate layer contains a second organic compound having a phenanthroline skeleton. The first light-emitting layer and the second light-emitting layer contain the same emission center substance.

Abstract: A light-emitting device having high emission efficiency is provided. The light-emitting device includes a light-emitting layer between a pair of electrodes. The light-emitting layer includes a first compound, a material configured to convert triplet excitation energy into light emission, and a material configured to convert singlet excitation energy into light emission. At least one of the first compound and the material configured to convert triplet excitation energy into light emission includes deuterium. Light emission is obtained from the material configured to convert singlet excitation energy into light emission.

Abstract: A novel organic compound and a light-emitting device using the organic compound are provided. The organic compound includes a benzofuropyrimidine skeleton or a benzothienopyrimidine skeleton, a first substituent, and a second substituent. The first substituent represents a carbazole skeleton. The second substituent represents any of a carbazole skeleton, a dibenzofuran skeleton, a tetraphenylsilane skeleton, and a triphenylene skeleton. The first substituent is bonded to a pyrimidine ring included in the benzofuropyrimidine skeleton or the benzothienopyrimidine skeleton. The second substituent is bonded to a benzene ring included in the benzofuropyrimidine skeleton or the benzothienopyrimidine skeleton.

Abstract: A highly reliable light-emitting device is provided. The light-emitting device includes a first electrode, a second electrode, and a light-emitting layer. The light-emitting layer is positioned between the first electrode and the second electrode. The light-emitting layer includes a first organic compound, a second organic compound, and a substance that can convert triplet excitation energy into light emission. The first organic compound includes a ?-electron deficient heteroaromatic ring. The second organic compound includes a ?-electron rich heteroaromatic ring or an aromatic amine skeleton. The first organic compound and the second organic compound each contain deuterium. A difference between the lowest triplet excitation level of the first organic compound and that of the second organic compound is less than or equal to 0.10 eV.

Abstract: A light-emitting device having excellent characteristics is provided. A light-emitting apparatus material contains an organic compound. In the light-emitting apparatus material, the inner product of a vector A connecting two most distant atoms in the lowest excited state of the organic compound and a vector B that is a transition dipole moment relating to light emission from the organic compound is greater than or equal to 2.5. The length of the vector A is represented in nm, and the magnitude of the vector B is represented in debye. The direction of the vector A is set such that an angle formed by the vector A and the vector B is less than or equal to 90°.

Abstract: To provide an organometallic complex that can be used as a light-emitting material. The organometallic complex is represented by General Formula (G1). In the formula, each of R2 and R8 represents a deuterated alkyl group having 1 to 10 carbon atoms, each of R1, R3 to R7, and R9 to R26 independently represents hydrogen (including deuterium), an alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, at least one of R4 to R6 represents an alkyl group having 1 to 10 carbon atoms, and at least one of R22 to R26 represents an alkyl group having 3 to 10 carbon atoms.

Abstract: An organic semiconductor device with low driving voltage is provided. The organic semiconductor device includes a layer containing an organic compound between a pair of electrodes. The layer containing an organic compound includes a hole-transport region. The hole-transport region includes a first layer and a second layer. The first layer is positioned between the anode and the second layer. When a potential gradient of a surface potential of an evaporated film is set as GSP (mV/nm), a value obtained by subtracting GSP of an organic compound in the second layer from GSP of an organic compound in the first layer is less than or equal to 20 (mV/nm).

Abstract: 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.

Abstract: A furopyrazine derivative that is a novel organic compound is provided. The organic compound has a furopyrazine skeleton and is represented by General Formula (G1). In General Formula (G1), Q represents oxygen or sulfur, Ar1 represents a substituted or unsubstituted condensed aromatic ring, R1 and R2 independently represent hydrogen or a group having 1 to 100 total carbon atoms, and at least one of R1 and R2 has a hole-transport skeleton.

Abstract: Provided is a novel organic compound, a benzofuropyrimidine derivative or a benzothienopyrimidine derivative, which is an organic compound represented by General Formula (G1) below. In General Formula (G1), Q represents oxygen or sulfur. Furthermore, A is a group having 12 to 100 carbon atoms in total and includes one or more of a benzene ring, a naphthalene ring, a fluorene ring, a phenanthrene ring, a triphenylene ring, a heteroaromatic ring including a dibenzothiophene ring, a heteroaromatic ring including a dibenzofuran ring, a heteroaromatic ring including a carbazole ring, a benzimidazole ring, and a triphenylamine structure.

Abstract: A light-emitting device with high resolution and high efficiency is provided. A first electrode, a second electrode, a first EL layer, an intermediate layer, and a second EL layer are provided, the first electrode is positioned to face the second electrode with the intermediate layer therebetween, the first EL layer is positioned between the first electrode and the intermediate layer, the second EL layer is positioned between the intermediate layer and the second electrode, and the intermediate layer contains an organic compound represented by General Formula (G1) below.

Abstract: A novel organometallic complex with high reliability is provided. A light-emitting element includes an EL layer between a pair of electrodes. The EL layer includes at least a light-emitting layer. The light-emitting layer contains an organometallic complex. The organometallic complex includes a first ligand and a second ligand which are coordinated to a central metal. The HOMO is distributed over the first ligand, and the LUMO is distributed over the second ligand. The first ligand and the second ligand are cyclometalated ligands.

Abstract: 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.

Abstract: An organic semiconductor device with low driving voltage is provided. The organic semiconductor device includes a layer containing an organic compound between a pair of electrodes. The layer containing an organic compound includes a hole-transport region. The hole-transport region includes a first layer and a second layer. The first layer is positioned between the anode and the second layer. When a potential gradient of a surface potential of an evaporated film is set as GSP (mV/nm), a value obtained by subtracting GSP of an organic compound in the second layer from GSP of an organic compound in the first layer is less than or equal to 20 (mV/nm).

Abstract: An organic compound having high heat resistance is provided. An organic compound represented by a general formula (G1) is provided. In the formula, Q represents carbon or silicon; each of R1 and R2 independently represents an alkyl group, a cycloalkyl group, or an aryl group; n represents an integer from 1 to 3; each of ?1 to ?4 independently represents a phenylene group or a biphenylene group; at least one of R15, R25, R31 and at least one of R45, R55, and R61 represent single bonds and the others thereof represent H, an alkyl group, or an aryl group; and R11 to R14, R21 to R24, R32 to R35, R41 to R44, R51 to R54, and R62 to R65 represent H, an alkyl group, a cycloalkyl group, or an aryl group.

Abstract: A novel compound and a light-emitting element with high emission efficiency and a long lifetime are provided. The novel compound includes a benzofuropyrazine skeleton or a benzothienopyrazine skeleton, and each of a benzene ring and a pyrazine ring in the benzofuropyrazine skeleton or the benzothienopyrazine skeleton independently includes a substituent with a total number of carbon atoms of 6 to 100 inclusive. The light-emitting element includes the compound.

Abstract: A benzofuropyrimidine derivative or benzothienopyrimidine derivative that is a novel organic compound is provided. An organic compound represented by General Formula (G1) below. Q represents oxygen or sulfur. Ar1, Ar2, Ar3, and Ar4 each independently represent an aromatic hydrocarbon ring, and the number of carbon atoms included in the aromatic hydrocarbon ring is 6 to 25. m and n are each 0 or 1. A is a group having 12 to 100 carbon atoms in total and includes one or more of a benzene ring, a naphthalene ring, a fluorene ring, a phenanthrene ring, a triphenylene ring, a heteroaromatic ring including a dibenzothiophene ring, a heteroaromatic ring including a dibenzofuran ring, a heteroaromatic ring including a carbazole ring, a benzimidazole ring, and a triphenylamine structure.

Abstract: A light-emitting element that includes a fluorescent material and has a high emission efficiency is provided. A light-emitting element in which a delayed fluorescence component due to TTA accounts for a high proportion of emissive components is provided. A novel light-emitting device with a high emission efficiency and a low power consumption is provided. A light-emitting element includes an anode, a cathode, and an EL layer. The EL layer includes a light-emitting layer including a host material and an electron-transport layer including a first material in contact with the light-emitting layer. The LUMO level of the first material is lower than that of the host material. The proportion of a delayed fluorescence component due to TTA is greater than or equal to 10 percent of the light emission from the EL layer. The proportion of the delayed fluorescence component due to TTA may be greater than or equal to 15 percent of the light emission.