A First-Order Transition of the Smectic A-Smectic C* in Ferroelectric Liquid Crystals

Abstract

The static dielectric constant is calculated as a function of temperature using a mean field model close to the smectic A-smectic C* transition for the ferroelectric liquid crystal 4-(3-methyl-2-chlorobutanoyloxy)-4'-heptyloxybiphenyl (A7). This calculation of the dielectric constant is performed for the pure optically active compound (T-c = 73.4 degrees C) and the temperature range is determined for a first-order smectic A-smectic C* transition from the mean field model. Our predicted values describe adequately the observed behaviour of the dielectric constant close to the smectic A-smectic C* transition and also the temperature range in the smectic A phase of A7.