Dielectric characteristics of chiral smectic C subphases in liquid crystal MHPOPB

Recently the antiferroelectric liquid crystal compound (MHPOPB), synthesized in the Institute of Chemistry, Military University of Technology (Warsaw), has been studied by means of low frequency dielectric spectroscopy. This compound shows a very broad temperature range of chiral smectic C subphases: the SmCα*, the SmCβ*, and the SmCγ* in the cooling process. The dielectric characteristics of these subphases are presented. In the SmCα* phase only a weak Goldstone mode was observed. In the SmCβ* phase a relaxation process of characteristic antiferroelectric ordering was observed. In the SmCγ* phase a ferrielectric Goldstone mode was registered. The temperature dependence of parameters describing these modes is also presented.