Dielectric spectroscopy study of the transition into the hexatic phase in chiral smectics

Abstract Collective molecular motion was studied by dielectric spectroscopy up to 10 MHz in the vicinity of both ferroelectric SmC*-hexatic SmI* and antiferroelectric SmC*A-hexatic SmI*A phase transitions. A single relaxation process has been found in all studied phases except for the SmC*A phase, where no relaxation process could be detected. These relaxations have been attributed to fluctuations of bond orientation order coupled to the tilt and polarization. This coupling is also responsible for the anomalous increase of Ps value at the transition to the hexatic phases.