Influence of Optical Purity on the Pressure-Temperature Phase Diagram of Antiferroelectric Liquid Crystals

Abstract

We have investigated the dielectric properties and the spontaneous polarization in antiferroelectric liquid crystals under pressure. In MHPOBC 52%ee, the width of the ferroelectric SmC^* phase slightly expanded as the pressure was increased. The spontaneous polarization and the dielectric constant showed a decrease only in low pressures. On the other hand, the SmC^* phase in R-MHPOBC vanished at least 50MPa. However, the SmC_α^* and SmC_γ^* phases did not vanish. Therefore, it is suggested that the stability of the SmC^* phase under pressure changes with changing optical purity.