Study of Molecular Orientational States and Dielectric Properties of Surface Stabilized Ferroelectric Liquid Crystals

Abstract

The study of the molecular orientational states and the dielectric properties of surface stabilized ferroelectric liquid crystals (SSFLCs) was reviewed. The molecular orientational models were presented and they gave us a total understanding of the orientational states which appear in SSFLCs with parallel rubbing. Using the molecular orientational models, the dielectric properties of SSFLCs were studied. Three dielectric permittivities were measured for each of two samples, the permittivity of the homeotropic cell and the permittivity of the planar homogeneous cell with and without the DC bias, and then the dielectric tensor components were calculated based on the molecular orientational models. Results for Merck SCE-8 are reported. The novel frequency dependence of the dielectric biaxiality was found. The sign of the dielectric biaxiality inverted around 1kHz, being negative at low frequencies and positive at high frequencies. The relationship between the dielectric behavior of SSFLC cells and the dielectric biaxiality is discussed.