X-ray and optical studies of an isothiocyanato liquid crystal mixture

Abstract

ABSTRACTIn this work, X-ray and optical studies have been carried out on a four-component isothiocyanato liquid crystal mixture with laterally substituted fluorine atoms. Molecular characteristics, such as effective inter molecular distances and apparent molecular length of the average-simulated molecule have been determined from X-ray studies at various temperatures in the liquid crystalline phase. From the nature of molecular alignment as envisaged from X-ray photographs, the orientational order parameter and its variation with temperature have been determined. Optical studies have also been conducted at various temperatures to investigate the thermal variations of birefringence. Macroscopic orientational order parameter and its thermal variation have been determined from these studies. The nature of order parameter variation obtained from the two studies, X-ray and optical have been compared.