Polarized FT-IR study on SmCβ* and SmC* of antiferroelectric liquid crystals

Abstract

Alignment of molecules and hindered rotation of molecular segments in SmCp* and SmC* of antiferroelectric and ferroelectric liquid crystals were studied by the polarized infrared absorption spectroscopy. The experimental results show that the apparent molecular tilt angle in SmC_β* increases not monotonously but as a two-step staircase with increasing dc bias field, and the characteristics of hindered rotation of carbonyl groups in unwound state of helix are the same as that of SmC*.

Keywords:

• antiferroelectric liquid crystal
• chiral smectic C_βphase
• polarized infrared absorption spectroscopy