Abstract: A substance having a hole-transport property and a wide band gap is provided. A fluorene compound represented by a general formula (G1) is provided. In the general formula (G1), ?1 and ?2 separately represent a substituted or unsubstituted arylene group having 6 to 13 carbon atoms; Ar1 represents a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, a substituted or unsubstituted 4-dibenzothiophenyl group, or a substituted or unsubstituted 4-dibenzofuranyl group; n and k separately represent 0 or 1; Q1 represents sulfur or oxygen; and R1 to R15 separately represent hydrogen, an alkyl group having 1 to 12 carbon atoms, or an aryl group having 6 to 14 carbon atoms.

Abstract: A novel substance with which an increase in life and emission efficiency of a light-emitting element can be achieved is provided. A carbazole compound having a structure represented by General Formula (G1) is provided. Note that a substituent which makes the HOMO level and the LUMO level of a compound in which a bond of the substituent is substituted with hydrogen deep and shallow, respectively is used as each of substituents in General Formula (G1) (R1, R2, Ar3, and ?3). Further, a substituent which makes the band gap (Bg) and the T1 level of a compound in which a bond of the substituent is substituted with hydrogen wide and high is used as each of the substituents in General Formula (G1) (R1, R2, Ar3, and ?3).

Abstract: A light-emitting element is provided, in which n (n is a natural number of two or more) EL layers are provided between an anode and a cathode. Between the m-th (in is a natural number, 1?m?n?1) EL layer and the (m+1)-th EL layer, a first layer containing any of an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal compound, an alkaline earth metal compound, and a rare earth metal compound, a second layer containing a substance having high electron-transport properties in contact with the first layer, and a charge-generation layer containing a substance having high hole-transport properties and an acceptor substance in contact with the second layer are provided in this order over the anode. The charge-generation layer does not have a peak of an absorption spectrum in a visible light region.

Abstract: A light-emitting element that emits light with high luminance and can be driven at low voltage. The light-emitting element includes n (n is a natural number greater than or equal to 2) EL layers between an anode and a cathode, and includes a first layer, a second layer, and a third layer between an m-th (m is a natural number, 1?m?n?1) EL layer from the anode and an (m+1)th EL layer. The first layer functions as a charge-generation region, has hole-transport properties, and contains an acceptor substance. The third layer has electron-transport properties and contains an alkali metal or the like. The second layer is formed of a phthalocyanine-based material and is provided between the first layer and the third layer, whereby an injection barrier at the time of injecting electrons generated in the first layer into the m-th EL layer through the third layer can be lowered.

Abstract: An object is to provide a light-emitting element with high emission efficiency which includes a novel carbazole derivative that has a wide energy gap and can be used for a transport layer or a host material in a light-emitting element. A carbazole derivative in which the 4-position of dibenzothiophene or dibenzofuran is bonded to the 2- or 3-position of carbazole has been able to be provided by use of the carbazole derivative. Further, a light-emitting element having high emission efficiency has been able to be provided by use of the carbazole derivative.

Abstract: A light-emitting element which emits light with high luminance and can be driven at low voltage. The light-emitting element includes n (n is a natural number of 2 or more) EL layers between an anode and a cathode, and includes a first layer, a second layer, and a third layer between an m-th (m is a natural number, 1?m?n?1) EL layer from the anode and an (m+1)th EL layer. The first layer functions as a charge-generation region, has hole-transport properties, and contains an acceptor substance. The third layer has electron-transport properties and contains an alkali metal or the like. The second layer formed of a metal complex having a metal-oxygen bond and an aromatic ligand is provided between the first and third layers, whereby an injection barrier at the time of injecting electrons generated in the first layer into the m-th EL layer through the third layer can be lowered.

Abstract: A novel substance with which an increase in life and emission efficiency of a light-emitting element can be achieved is provided. A carbazole compound having a structure represented by General Formula (G1) is provided. Note that a substituent which makes the HOMO level and the LUMO level of a compound in which a bond of the substituent is substituted with hydrogen deep and shallow, respectively is used as each of substituents in General Formula (G1) (R1, R2, Ar3, and ?3). Further, a substituent which makes the band gap (Bg) and the T1 level of a compound in which a bond of the substituent is substituted with hydrogen wide and high is used as each of the substituents in General Formula (G1) (R1, R2, Ar3, and ?3).

Abstract: Provided are a light-emitting element in which a driving voltage increase can be suppressed and a light-emitting device which has reduced power consumption by including the light-emitting element. The element includes an EL layer between an anode and a cathode, and has a first, a second, and a third layer between the cathode and the EL layer. The first layer is between and in contact with the cathode and the second layer and includes a hole-transport substance. The second layer is between and in contact with the first the third layers and includes a phthalocyanine-based material. The third layer is between and in contact with the second and EL layers and includes an alkali metal, an alkaline-earth metal, a rare-earth metal, an alkali metal compound, an alkaline-earth metal compound, or a rare-earth metal compound. The phthalocyanine-based material has a metal-oxygen bond.

Abstract: Provided is a novel substance that can emit phosphorescence. Alternatively, provided is a novel substance with high emission efficiency. An organometallic complex in which a 4-arylpyrimidine derivative is a ligand and iridium is a central metal is provided. Specifically, an organometallic complex having a structure represented by a general formula (G1) is provided. In the general formula (G1), R1 represents a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms or a substituted or unsubstituted aryl group having 6 to 10 carbon atoms, R2 represents any of hydrogen, a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, and a substituted or unsubstituted phenyl group, R3 represents hydrogen or a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, and Ar1 represents a substituted or unsubstituted arylene group having 6 to 10 carbon atoms.

Abstract: A light-emitting element includes an EL layer between an anode and a cathode, and a first layer, a second layer, and a third layer between the cathode and the EL layer. The first layer provided between the cathode and the second layer is in contact with the cathode and the second layer, and includes a substance having a hole-transport property and an acceptor substance. The second layer provided between the first layer and the third layer is in contact with the first layer and the third layer, and includes a phthalocyanine-based material. The third layer provided between the second layer and the EL layer is in contact with the second layer and the EL layer, and includes an alkali metal, an alkaline-earth metal, a rare-earth metal, an alkali metal compound, an alkaline-earth metal compound, or a rare-earth metal compound.

Abstract: A substance having a hole-transport property and a wide band gap is provided. A fluorene compound represented by a general formula (G1) is provided. In the general formula (G1), ?1 and ?2 separately represent a substituted or unsubstituted arylene group having 6 to 13 carbon atoms; Ar1 represents a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, a substituted or unsubstituted 4-dibenzothiophenyl group, or a substituted or unsubstituted 4-dibenzofuranyl group; n and k separately represent 0 or 1; Q1 represents sulfur or oxygen; and R1 to R15 separately represent hydrogen, an alkyl group having 1 to 12 carbon atoms, or an aryl group having 6 to 14 carbon atoms.

Abstract: In the light-emitting element in which a plurality of EL layers is separated from each other by a charge generation layer, provided are an electron relay layer in contact with an anode side of the charge generation region and an electron transport layer in contact with the electron relay layer. The electron transport layer contains an alkaline earth metal. A concentration gradient of the alkaline earth metal contained in the electron transport layer is such that the concentration of the alkaline earth metal becomes lower from an interface between the electron transport layer and the electron relay layer to the anode.

Abstract: An object is to provide a light-emitting element which exhibits light emission with high luminance and can be driven at low voltage. Another object is to provide a light-emitting device or an electronic device with reduced power consumption. Between an anode and a cathode, n (n is a natural number of two or more) EL layers are provided, where between a first EL layer and a second EL layer, a first layer containing any of an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal compound, an alkaline earth metal compound, and a rare earth metal compound, a second layer containing a material having a high electron-transporting property in contact with the first layer, and a region containing a material having a high hole-transporting property and an acceptor material in contact with the second layer are provided in this order from the anode side.

Abstract: Provided is a novel substance that can emit phosphorescence. Alternatively, provided is a novel substance with high emission efficiency. An organometallic complex in which a 4-arylpyrimidine derivative is a ligand and iridium is a central metal is provided. Specifically, an organometallic complex having a structure represented by a general formula (G1) is provided. In the general formula (G1), R1 represents a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms or a substituted or unsubstituted aryl group having 6 to 10 carbon atoms, R2 represents any of hydrogen, a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, and a substituted or unsubstituted phenyl group, R3 represents hydrogen or a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, and Ar1 represents a substituted or unsubstituted arylene group having 6 to 10 carbon atoms.

Abstract: Light-emitting elements in which an increase of driving voltage can be suppressed are provided. Light-emitting devices whose power consumption is reduced by including such light-emitting elements are also provided. In a light-emitting element having an EL layer between an anode and a cathode, a first layer in which carriers can be produced is formed between the cathode and the EL layer and in contact with the cathode, a second layer which transfers electrons produced in the first layer is formed in contact with the first layer, and a third layer which injects the electrons received from the second layer into the EL layer is formed in contact with the second layer.

Abstract: A substance having a hole-transport property and a wide band gap is provided. A heterocyclic compound represented by a general formula (G1) is provided. In the formula, ?1 and ?2 separately represent a substituted or unsubstituted arylene group having 6 to 13 carbon atoms; n and k separately represent 0 or 1; Q1 and Q2 separately represent sulfur or oxygen; and R1 to R22 separately represent hydrogen, an alkyl group having 1 to 12 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 14 carbon atoms.

Abstract: Light-emitting elements in which an increase of driving voltage can be suppressed are provided. Light-emitting devices whose power consumption is reduced by including such light-emitting elements are also provided. In a light-emitting element having an EL layer between an anode and a cathode, a first layer in which carriers can be produced is formed between the cathode and the EL layer and in contact with the cathode, a second layer which transfers electrons produced in the first layer is formed in contact with the first layer, and a third layer which injects the electrons received from the second layer into the EL layer is formed in contact with the second layer.

Abstract: A substance having a hole-transport, property and a wide band gap is provided. A heterocyclic compound represented by a general formula (G1) is provided. In the formula, ?1 and ?2 separately represent a substituted or unsubstituted arylene group having 6 to 13 carbon atoms; n and k separately represent 0 or 1; Q1 and Q2 separately represent sulfur or oxygen; and R1 to R22 separately represent hydrogen, an alkyl group having 1 to 12 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 14 carbon atoms.

Abstract: An object is to provide a light-emitting element with high emission efficiency which includes a novel carbazole derivative that has a wide energy gap and can be used for a transport layer or a host material in a light-emitting element. A carbazole derivative in which the 4-position of dibenzothiophene or dibenzofuran is bonded to the 2- or 3-position of carbazole has been able to be provided by use of the carbazole derivative. Further, a light-emitting element having high emission efficiency has been able to be provided by use of the carbazole derivative.

Abstract: An object is to provide a light-emitting element with high emission efficiency which includes a novel carbazole derivative that has a wide energy gap and can be used for a transport layer or a host material in a light-emitting element. A carbazole derivative in which the 4-position of dibenzothiophene or dibenzofuran is bonded to the 2- or 3-position of carbazole has been able to be provided by use of the carbazole derivative. Further, a light-emitting element having high emission efficiency has been able to be provided by use of the carbazole derivative.