Premium
Ordering and mobility of ferroelectric liquid crystal dimer as studied by FT‐IR spectroscopy with 2D‐IR correlation analysis
Author(s) -
Shilov Sergej V.,
Skupin Holger,
Kremer Friedrich,
Wittig Tobias,
Zentel Rudolf
Publication year - 1997
Publication title -
macromolecular symposia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.257
H-Index - 76
eISSN - 1521-3900
pISSN - 1022-1360
DOI - 10.1002/masy.19971190127
Subject(s) - mesogen , liquid crystal , ferroelectricity , dimer , materials science , methylene , infrared spectroscopy , crystallography , electric field , phase (matter) , side chain , chemistry , polymer , organic chemistry , composite material , optoelectronics , liquid crystalline , dielectric , physics , quantum mechanics
Both a conservative rapid‐scan FT‐IR technique and a novel step‐scan FT‐IR technique with 2D correlation analysis were used to study the orientation and the mobility of a ferroelectric liquid crystal dimer during switching under an electric field. The detailed mutual arrangements of different molecular segments (mesogen, poly(methylene) chain, polysiloxane chain) in a smectic C* phase were derived from the static spectra. It was shown that the long mesogen axis, the average poly(methylene) and the average polysiloxane chain axes do not coincide with each other. The hindered rotation of the carbonyl group is confirmed. Time‐resolved FT‐IR technique was used to follow the segmental motion with a time resolution of 5 μs. The temperature and electric field strength dependencies of the mobility of these segments are discussed. 2D correlation analysis of time‐resolved data reveals small differences in the behavior of the carbonyl and the benzoic rings in the mesogen moieties, that can be explained as differences in the orientation distribution functions of these moieties.