New temperature scan method (TSM) for revealing the chiral smectic polar phases

A new simple and reliable method to identify the antiferro-, ferri- and ferro-electric and the SCα phases has been worked out, involving temperature scanning of the liquid crystalline sample under a square wave electric field. The d.c. current recorded during the temperature run provides information about the phases and the phase transition temperatures. The resolution power of the method is checked by the study of three compounds. The results obtained by this new Temperature Scan Method (TSM) are compared to those found from dielectric measurements and from the study of the optical and dielectric hysteresis loops.