Liquid crystal composition and liquid crystal display device

A liquid crystal composition that has a nematic phase, and contains at least one compound selected from the group of optically active compounds each having an octahydro binaphthalene skeleton or a binaphthalene skeleton represented by formula (1) and formula (2) as an additive, and at least one compound selected from the group of compounds represented by formula (3) as a first component:

• wherein, in formula (1) and formula (2), R1, R2 and R3 are independently hydrogen, halogen, cyano, —SF5 or alkyl having 1 to 10 carbons, and in the alkyl, at least one —CH2— may be replaced by —O—, —COO—, —OCO—, —CH═CH— or —C≡C—, and in the groups, at least one hydrogen may be replaced by fluorine or chlorine;
• ring A, ring B, ring E and ring F are independently 5,6,7,8-tetrahydronaphthalene-1,2-diyl or naphthalene-1,2-diyl;
• ring C, ring D and ring G are independently 1,4-cyclohexylene, 1,4-phenylene, 1,3-dioxane-2,5-diyl, tetrahydropyran-2,5-diyl, tetrahydropyran-3,5-diyl, pyrimidine-2,5-diyl, pyridine-2,5-diyl or 1,4-bicyclo-(2,2,2)-octylene, and in the rings, at least one hydrogen may be replaced by fluorine or chlorine;
• Z1, Z2, Z3, Z4 and Z5 are independently a single bond or alkylene having 1 to 20 carbons, and in the alkylene, at least one —CH2— may be replaced by —O—, —CO—, —COO—, —OCO—, —CH═CH— or —C≡C—, and in the groups, at least one hydrogen may be replaced by fluorine or chlorine;
• and a, b and c are independently 2, 3 or 4, and
• in formula (3), R4 and R5 are independently alkyl having 1 to 12 carbons, alkoxy having 1 to 12 carbons, alkenyl having 2 to 12 carbons, or alkenyl having 2 to 12 carbons in which at least one hydrogen is replaced by fluorine or chlorine;
• ring I and ring J are independently 1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene or 2,5-difluoro-1,4-phenylene;
• Z6 is a single bond, ethylene or carbonyloxy;
• and d is 1, 2 or 3.