Cholesterol-based photo-switchable mesogenic dimers. Strongly bent molecules versus an intercalated structure

A homologous series of cholesterol-based liquid crystalline dimers were synthesized and characterized by polarizing optical microscopy, DSC, and powder and single-crystal XRD.

Bent-core dimers with top-to-bottom linkage between central units

A structurally new type of core-to-core dimer with a top-to-bottom linkage between the central cores of bent molecules is presented. The structure of the bent-core molecules was modified by changing the length of the spacer between the central cores and terminal chains, by changing the type of linkage groups in the bent-core arms and by variation of the terminal chain polarity – introducing polyfluoroalkyl and oligosiloxane units. Additionally, the outer phenyl ring was substituted with three alkyl chains to mimic a polycatenar system. For all compounds the mesophase behaviour and structural parameters were established to gain information about the molecular structure–mesomorphic property relationship.

A study of bent-core liquid crystalline dimers with a unique top-to-bottom molecular structure.

Core-to-core dimers forming switchable mesophase

We report structurally new type of dimers composed of bent-core molecules connected through their central cores by an alkylene spacer. Various self-assembling structures are discovered when prolonging the terminal alkyl chains in arms. Among diverse mesophases, the antiferroelectric type of switching under an applied electric field is observed.