Dielectric properties of subphases SmC~*_α and SmC~*γ in an antiferroelectric liquid crystal

摘要

Recently synthesized in Institute of Chemistry, Military University of Technology (Warsaw), antiferroelectric liquid crystal compound ( MHPOPOPC) has been studied by means of low frequency dielectric spectroscopy. This compound shows very broad temperature range of ferrielectric subphases: the SmC~*_α, the SmC~*_β, and the SmC~*_γ in cooling process. The dielectric characteristic of these subphases are presented. In the SmC~*_α phase only soft mode was observed which suggest the antiferroelectric nature of this subphase in the investigated compound. In the SmC~*_β, phase relaxation process of characteristic antiferroelectric ordering was observed. In the SmC~*_γ ferrielectric Goldstone mode was registered. The temperature dependence of parameter of these modes were presented.