Dielectric relaxation of a nematic eutectic mixture with a high glass temperature

Abstract

Dielectric relaxation measurements in the frequency range from 2 Hz to 100 kHz have been carried out on an oriented binary nematic mixture of low molecular liquid crystals with a glass temperature of 307 K. For both relaxation frequencies, f _R‖ and f _R⊥, a glass behaviour according to the Vogel-Fulcher law could be detected. The Cole-Cole distribution parameter for reorientation around the long molecular axis increases strongly with decreasing temperature. This effect is discussed with regard to the optical biaxiality of the mixture.