CHIRAL DISCRIMINATION EFFECT IN REENTRANT LIQUID-CRYSTALS

In order to study the effect of varying chirality on re-entrant phenom ena in liquid crystals, we determined temperature-chirality-chain-leng th phase surfaces for phase transitions in mixtures of racemic and ena ntiomeric compounds belonging to a novel AZY series. We observed that the location of the chiral nematic-partly bilayer smectic-A-chiral re- entrant nematic (N-SmA(d)-N(re*) double-critical point depends signif icantly on chirality, and determined some relevant thermodynamic param eters. We argue that this effect is due to the chiral discrimination i n orientationally ordered but untwisted media.