Calorimetric and optical microscopic studies on one ferroelectric liquid-crystal compound with the smectic-A/emph> phase

Detailed calorimetric measurements have been carried out on the chiral and racemic versions of one chiral liquid-crystal compound that exhibits an unusual and new smectic-A* (Sm-A*) phase in the pure chiral compound. Both the smectic-A (Sm-A)smectic-C (Sm-C) transition in the racemic compound and the Sm-A*chiralSm-C transition in the pure chiral compound display a first-order transition with heat-capacity anomalies qualitatively similar to but quantitatively different from that observed in the ordinary Sm-ASm-C transition. Results from optical microscopic studies on the phase diagram of binary mixtures of the dextro and levo versions of the chiral compounds are reported.