Thermodynamic Model to Study the Phase Transition Properties of SmC_A^* Phase in Antiferroelectric Mesogen W-358 Series

Abstract

Employing the thermodynamic model which is centred on Landau-de-Gennes theory, the electro-optical properties of the Sm  phase in antiferroelectric mesogen has been studied. The wave vector q, the polarisation vector P, and the couplings between these order parameters are used to express the system's free-energy density. The Landau coefficients involved in the free-energy density have been computed using experimental data of tilt angle and spontaneous polarisation in the Sm  phase of chiral compounds (6F2OBi and 3F5HBM6(S)). Theoretical and experimental data have been compared in investigations