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After preparing a biphenyl derivative possessing two 2,3-difluoro-1,4-diphenylbenzene units, we investigated its phase transition behaviour. It showed a phase sequence of isotropic liquid–nematic phase–anticlinic smectic C phase. A mixture with a chiral additive with a high twisting power exhibited a cubic blue phase and/or an amorphous blue phase III (BPIII). The compound doped with 10 wt% of the chiral additive showed a phase sequence of Iso 85.4 °C BPIII 70.6 °C cubic BP 47.3 °C chiral nematic 37.3 °C unidentified smectic phase. We investigated electro-optical switching in BPIII and in the cubic BP of the mixture. Transmittance without an applied electric field in the BPIII was 0%, whereas that in the cubic BP was 4.6%. Threshold and driving voltages in the BPIII are lower than in the cubic BP. Furthermore, the BPIII exhibits no voltage-induced hysteresis effects on transmittance. Amorphous BPIII has superior potential for use in next-generation displays. [ABSTRACT FROM AUTHOR]

Supermolecules composed of pre-organized mesogenic units have attracted much attention because they can form secondary and tertiary structures with unique physical properties. This Feature Article reviews recent progress in thermotropic supermolecular liquid-crystalline materials with a hierarchical structure. We take the concepts of molecular dynamics, electrostatic core–core interactions, hydrocarbon–fluorocarbon amphiphilicity and intramolecular chirality transfer, and apply them to the creation of new materials. The liquid crystal oligomers in which conventional mesogenic units are pre-organized in a classical shape can produce unusual phase structures and unique physical properties. [ABSTRACT FROM AUTHOR]

A novel dichiral compound possessing both an asymmetric axis and a chiral centre induces opposite twist senses and distinct helical pitches in different host nematic liquid crystals; the host–guest effect on chirality transfer is discussed in terms of molecular recognition. [ABSTRACT FROM AUTHOR]