Vibrational Studies on the Dynamics of Switching between the Surface-Stabilized States of a Ferroelectric Liquid Crystal by Asynchronous Time-Resolved Fourier Transform Infrared Spectroscopy

Time-resolved polarized infrared spectra have been observed from a ferroelectric liquid crystal (chiral smectic C phase) consisting of a chiral dopant and a nonchiral smectic base during the course of switching between the surface-stabilized states. A primary fast process and the subsequent slow process have been observed for all infrared bands. The chiral dopant and smectic base molecules move simultaneously. The observed time behavior of the infrared bands can be mostly explained by the reorientation of a rigid molecule whose rotational motion around the molecular long axis is almost free. The static intensities and the time behavior of the ester and keto C=O stretching bands do not seem to be consistent with the simple view on the role of these groups.