Optically isotropic liquid crystal medium, and optical device

A liquid crystal composition, comprising a compound of Formula (1) and a chiral dopant, and exhibiting an optically isotropic liquid crystal phase:

• wherein in Formula (1), R1 is hydrogen or a C1-20 alkyl, wherein arbitrary —CH2— in the alkyl may be replaced by —O—, —S—, —COO—, —OCO—, —CH═CH—, —CF═CF—, or —C≡C—, and arbitrary hydrogen in the alkyl and the alkyl with arbitrary —CH2— replaced by —O—, —S—, —COO—, —OCO—, —CH═CH—, —CF═CF—, or —C≡C— may be replaced by halogen or a C1-3 alkyl;
• rings A1, A2, A3, A4, and A5 are independently a benzene ring, naphthalene ring, thiophene ring, piperidine ring, cyclohexene ring, bicyclo-octane ring, tetrahydronaphthalene ring, or a cyclohexane ring, where arbitrary hydrogen in the rings may be replaced by halogen, a C1-3 alkyl, a C1-3 alkoxy, or a C1-3 haloalkyl, —CH2— in the rings may be replaced by —O— or —S—, —CH═ may be replaced by —N═;
• Z1, Z2, Z3, Z4, Z5, and Z6 are independently a single bond or a C1-4 alkylene, wherein arbitrary —CH2— in the alkylene may be replaced by —O—, —S—, —COO—, —OCO—, —CSO—, —OCS—, —CH═CH—, —CF═CF—, or —C≡C—, and arbitrary hydrogen in the alkylene and the alkylene with arbitrary —CH2— replaced by —O—, —S—, —COO—, —OCO—, —CSO—, —OCS—, —CH═CH—, —CF═CF—, or —C≡C— may be replaced by halogen, provided that at least one of Z1, Z2, Z3, Z4, Z5, and Z6 is —CF2O—;
• L1 and L2 are independently hydrogen or halogen;
• X1 is hydrogen, halogen, —C≡N, —N═C═S, —C≡C—C≡N, —SF5, or a C1-10 alkyl, wherein arbitrary —CH2— in the alkyl may be replaced by —O—, —S—, —CH═CH—, or —C≡C—, and arbitrary hydrogen in the alkyl and the alkyl with arbitrary —CH2— replaced by —O—, —S—, —CH═CH—, or —C≡C— may be replaced by halogen;
• and l, m, n, o, and p are independently 0 or 1, and l+m+n+o+p≦4.