Chirality in Liquid Crystals

Phosphoric acids as amplifiers of molecular chirality in liquid crystalline media.

[structure: see text] A new system for the double amplification of the molecular chirality of simple chiral amines in achiral liquid crystalline media is described. It involves a conformationally flexible phosphoric acid based receptor that by binding to chiral amines induces chirality in the liquid crystalline matrix. Efficient cholesteric phase formation was shown by several chiral amines tha...

Weak Chirality in Ordered Dna Phases

Recent experiments on aligned DNA show hexatic order with no sign of macroscopic chirality. I make the analogy between smectic liquid crystals and chiral hexatics and show how the absence of chirality cannot occur in a thermodynamic phase of chiral molecules. In addition, I discuss the microscopic origin of chiral mesophases in liquid crystals and show that, within the context of central forces...

Correlation length and chirality of the fluctuations in the isotropic phase of nematic and cholesteric liquid crystals.

Light-scattering measurements of the correlation length in the isotropic phase of a nematic liquid crystal reveal a temperature dependence following Landau-de Gennes theory for the isotropic phase with a bare correlation length smaller than has been measured in other liquid crystals. Similar measurements in a cholesteric liquid crystal demonstrate that the correlation length in the isotropic ph...

New electromechanical effect in chiral smectic C* liquid crystals

Order and Frustration in Chiral Liquid Crystals

This paper reviews the complex ordered structures induced by chirality in liquid crystals. In general, chirality favors a twist in the orientation of liquidcrystal molecules. In some cases, as in the cholesteric phase, this favored twist can be achieved without any defects. More often, the favored twist competes with applied electric or magnetic fields or with geometric constraints, leading to ...

Phase behavior in the reentrant-nematic region of chiral frustrated smectic liquid crystals

A high-resolution ac calorimetric study has been carried out on two homologous polar liquid crystals with aromatic cores containing three phenyl groups and a flexible chiral linking group. The expected smectic polymorphism occurs, and there are several prominent thermal features in the nematic range between smecticAd and smectic-C̃ phases. It is suggested on the basis of characteristic thermal s...