Liquid crystal composition and liquid crystal display device using the same

A liquid crystal composition comprising at least one compound represented by general formula (i):

• in the formula, Ri1 represents an alkynyl group having 2 to 12 carbon atoms, one —CH2— or two or more non-adjacent —CH2— in the alkynyl group may each independently be substituted with —CH═CH—, —C≡C—, —O—, —CO—, —COO—, or OCO—, and one or two or more hydrogen atoms present in Ri1 may each independently be substituted with a fluorine atom,
• Yi1 represents a hydrogen atom, a cyano group, or an alkyl group having 1 to 12 carbon atoms, one —CH2— or two or more non-adjacent —CH2— in the alkyl group may each independently be substituted with —CH═CH—, —C≡C—, —O—, —CO—, —COO—, or OCO—,
• Xi1 to Xi4 each independently represent a hydrogen atom or a fluorine atom, Xi1 and Xi2 never represent fluorine atoms at the same time, Xi3 and Xi4 never represent fluorine atoms at the same time, but at least one of Xi1 to Xi4 is a fluorine atom,
• Ai1 represents a group selected from the group consisting of:
• (a) a 1,4-cyclohexylene group, one —CH2— or two or more non-adjacent —CH2— present in this group may each be substituted with —O—,
• (b) a 1,4-phenylene group, one —CH═ or two or more non-adjacent —CH═ present in this group may each be substituted with —N═, and
• (c) a naphthalene-2,6-diyl group, a 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, or a decahydronaphthalene-2,6-diyl group, one —CH═ or two or more non-adjacent —CH═ present in the naphthalene-2,6-diyl group or the 1,2,3,4-tetrahydronaphthalene-2,6-diyl group may each be substituted with —N═,
• where the group (a), the group (b), and the group (c) may each independently be substituted with a halogen atom or a cyano group,
• Zi1 represents —OCH2—, —CH2O—, —C2H4—, —C4H8—, —COO—, —OCO—, —CH═CH—, —CF═CF—, —CF2O—, —OCF2—, —CF2CF2—, —C≡C— or a single bond, and
• mi1 represents 0 or 1.