Abstract: A light-emitting element that contains a fluorescent compound, which has high efficiency is provided. A light-emitting element in which the proportion of delayed fluorescence to the total light emitted from the light-emitting element is higher than that in a conventional light-emitting element is provided. Emission efficiency of the light-emitting element containing a fluorescent compound can be improved by increasing the probability of TTA caused by an organic compound in an EL layer, converting energy of triplet excitons, which does not contribute to light emission, into energy of singlet excitons, and making the fluorescent compound emit light by energy transfer of the singlet excitons.

Abstract: To provide a light-emitting element having high luminous efficiency and to provide a light-emitting device and an electronic device which consumes low power and is driven at low voltage, a carbazole derivative represented by the general formula (1) is provided. In the formula, ?1, ?2, ?3, and ?1 each represent an azylene stoup having less than or equal to 13 carbon atoms; Ar1 and Ar2 each represent an aryl group having less than or equal to 13 carbon atoms; R1 represents any of a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted phenyl group, and a substituted or unsubstituted biphenyl group; and R2 represents any of an alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted phenyl group, and a substituted or unsubstituted biphenyl group. In addition, l, m, and n are each independently 0 or 1.

Abstract: A light-emitting element with high emission efficiency and high reliability is provided. The light-emitting element includes a light-emitting layer containing a first organic compound, a second organic compound, and a guest material. The first organic compound has a nitrogen-containing six-membered heteroaromatic skeleton. In the light-emitting layer, the weight ratio of an organic compound having a nitrogen-containing five-membered heterocyclic skeleton with an NH group, a secondary amine skeleton with an NH group, or a primary amine skeleton with an NH group to the first organic compound is less than or equal to 0.03, or alternatively, the weight ratio of the organic compound having a nitrogen-containing five-membered heterocyclic skeleton with an NH group, a secondary amine skeleton with an NH group, or a primary amine skeleton with an NH group to the second organic compound is less than or equal to 0.01.

Abstract: To provide a light-emitting element with high emission efficiency. In a light-emitting element including an organic compound between a pair of electrodes, the molecular weight X of the organic compound is 450 or more and 1500 or less, and the absorption edge of the organic compound is at 380 nm or more. By liquid chromatography mass spectrometry in a positive mode in which an argon gas is made to collide with the organic compound subjected to separation using a liquid chromatograph at any energy higher than or equal to 1 eV and lower than or equal to 30 eV, a product ion is detected at least around m/z=(X?240).

Abstract: An object is to provide a light-emitting element having high light-emission efficiency by provision of a novel fluorene derivative as represented by General Formula (G1) below In the formula, R1 to R8 independently represent any of a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted phenyl group, or a substituted or unsubstituted biphenyl group. Further, ?1 to ?4 independently represent any of a substituted or unsubstituted arylene group having 6 to 12 carbon atoms. Furthermore, Ar1 and Ar2 independently represent any of an aryl group having 6 to 13 carbon atoms in a ring and Ar3 represents an alkyl group having 1 to 6 carbon atoms or a substituted or unsubstituted aryl group having 6 to 12 carbon atoms. J, k, m, and n each independently represent 0 or 1.

Abstract: A light-emitting element includes a light-emitting layer including a guest, an n-type host and a p-type host between a pair of electrodes, where the difference between the energy difference between a triplet excited state and a ground state of the n-type host (or p-type host) and the energy difference between a triplet excited state and a ground state of the guest is 0.15 eV or more. Alternatively, in such a light-emitting element, the LUMO level of the n-type host is higher than the LUMO level of the guest by 0.1 eV or more, or the HOMO level of the p-type host is lower than the HOMO level of the guest by 0.1 eV or more.

Abstract: A highly reliable light-emitting element having high emission efficiency is provided. The light-emitting element includes a light-emitting layer including a first organic compound and a guest material. The first organic compound has a substituted or unsubstituted carbazole skeleton. In the light-emitting layer, the weight ratio of a hydrocarbon group substitution product in which at least one of hydrogen atoms in the first organic compound is substituted by a hydrocarbon group having 1 to 6 carbon atoms to the first organic compound is greater than 0 and less than or equal to 0.1.

Abstract: To provide a novel fluorescent organic compound (a fluorescent compound). The organic compound is a substance that emits fluorescence and an organic compound (a host material) in which TTA can occur efficiently. In the organic compound, triplet excitons, which do not contribute to light emission, can be efficiently converted into singlet excitons. The use of such an organic compound can increase emission efficiency of a light-emitting element.

Abstract: To provide a light-emitting element having high luminous efficiency and to provide a light-emitting device and an electronic device which consumes low power and is driven at low voltage, a carbazole derivative represented by the general formula (1) is provided. In the formula, ?1, ?2, ?3, and ?4 each represent an arylene group having less than or equal to 13 carbon atoms; Ar1 and Ar2 each represent an aryl group having less than or equal to 13 carbon atoms; R1 represents any of a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted phenyl group, and a substituted or unsubstituted biphenyl group; and R2 represents any of an alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted phenyl group, and a substituted or unsubstituted biphenyl group. In addition, l, m, and n are each independently 0 or 1.

Abstract: An object is to provide a light-emitting element having high light-emission efficiency by provision of a novel fluorene derivative as represented by General Formula (G1) below. In the formula, R1 to R8 independently represent any of a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted phenyl group, or a substituted or unsubstituted biphenyl group. Further, ?1 to ?4 independently represent any of a substituted or unsubstituted arylene group having 6 to 12 carbon atoms. Furthermore, Ar1 and Ar2 independently represent any of an aryl group having 6 to 13 carbon atoms in a ring and Ar3 represents an alkyl group having 1 to 6 carbon atoms or a substituted or unsubstituted aryl group having 6 to 12 carbon atoms. J, k, m, and n each independently represent 0 or 1.

Abstract: A composite material which includes an organic compound and an inorganic compound and has a high carrier-transport property is provided. A composite material having a good property of carrier injection into an organic compound is provided. A composite material in which light absorption due to charge-transfer interaction is unlikely to occur is provided. A composite material having a high visible-light-transmitting property is provided. A composite material including a hydrocarbon compound and an inorganic compound exhibiting an electron-accepting property with respect to the hydrocarbon compound is provided. The hydrocarbon compound has a substituent bonded to a naphthalene skeleton, a phenanthrene skeleton, or a triphenylene skeleton and has a molecular weight of 350 to 2000, and the substituent has one or more rings selected from a benzene ring, a naphthalene ring, a phenanthrene ring, and a triphenylene ring.

Abstract: A novel organic compound is provided. An organic compound that emits light with high chromaticity is provided. An organic compound that emits blue light with high chromaticity is provided. An organic compound with high emission efficiency is provided. An organic compound having an excellent hole-transport property is provided. An organic compound having high reliability is provided. An organic compound that has a naphtho[2,3-b;7,6-b?]bisbenzofuran skeleton or a naphtho[2,3-b;7,6-b?]bisbenzothiophene skeleton and has a molecular weight of less than or equal to 5000 is provided. The present inventors have found that the organic compound is a significantly effective skeleton as a luminophor of a light-emitting element. The organic compound has high emission efficiency and exhibits favorable blue light emission; thus, a light-emitting element using the organic compound can be a blue light-emitting element with high emission efficiency.

Abstract: A light-emitting element includes a light-emitting layer including a guest, an n-type host and a p-type host between a pair of electrodes, where the difference between the energy difference between a triplet excited state and a ground state of the n-type host (or p-type host) and the energy difference between a triplet excited state and a ground state of the guest is 0.15 eV or more. Alternatively, in such a light-emitting element, the LUMO level of the n-type host is higher than the LUMO level of the guest by 0.1 eV or more, or the HOMO level of the p-type host is lower than the HOMO level of the guest by 0.1 eV or more.

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 subsistent 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 emitting phosphorescence and having high emission efficiency, in which a property of injecting holes to a light-emitting layer is increased, is provided. The light-emitting layer of the light-emitting element includes a first organic compound represented by the following general formula (G1) and a second organic compound which is a phosphorescent compound. The difference between the HOMO level of the first organic compound and the HOMO level of the second organic compound is lower than or equal to 0.3 eV.

Abstract: A novel light-emitting element or a highly reliable light-emitting element is provided. The light-emitting element includes an anode, a cathode, and an EL layer between the anode and the cathode. The EL layer includes at least a light-emitting layer. The light-emitting layer includes at least a first organic compound and a second organic compound. The energy for liberating halogen from a halogen-substituted product of the first organic compound in a radical anion state and in a triplet excited state is less than or equal to 1.00 eV. The amount of halogen-substituted product in the second organic compound is not increased with an increase in driving time of the light-emitting element.

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 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 subsistent 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: To increase emission efficiency of a fluorescent light-emitting element by efficiently utilizing a triplet exciton generated in a light-emitting layer. The light-emitting layer of the light-emitting element includes at least a host material and a guest material. The triplet exciton generated from the host material in the light-emitting layer is changed to a singlet exciton by triplet-triplet annihilation (TTA). The guest material (fluorescent dopant) is made to emit light by energy transfer from the singlet exciton. Thus, the emission efficiency of the light-emitting element is improved.

Abstract: A composite material which includes an organic compound and an inorganic compound and has a high carrier-transport property is provided. A composite material having a good property of carrier injection into an organic compound is provided. A composite material in which light absorption due to charge-transfer interaction is unlikely to occur is provided. A composite material having a high visible-light-transmitting property is provided. A composite material including a hydrocarbon compound and an inorganic compound exhibiting an electron-accepting property with respect to the hydrocarbon compound is provided. The hydrocarbon compound has a substituent bonded to a naphthalene skeleton, a phenanthrene skeleton, or a triphenylene skeleton and has a molecular weight of 350 to 2000, and the substituent has one or more rings selected from a benzene ring, a naphthalene ring, a phenanthrene ring, and a triphenylene ring.