On the coexistence of SmC* and SmC_A* phases in binary chiral-dopant antiferroelectric mixtures

Abstract

We present the results from investigations on a series of binary chiral-dopant liquid-crystalline mixtures. The racemic host materials possess tilted smectic phases with varying strengths of synclinic and anticlinic ordering (SmC and SmC_Aphases respectively). The dopants used were either a strongly synclinic-favouring non liquid-crystalline chiral material (commonly used in FLC chiral-dopant mixtures) or a strongly anticlinic (antiferroelectric) material ((S)-MHPOBC). The electrooptic and dielectric properties of the mixtures were investigated in test cells of different thickness and the influence of each mixture component on the observed physical properties is discussed.

Keywords:

• Ferroelectric
• antiferroelectric
• phase coexistence
• cell thickness
• electrooptics
• dielectric spectroscopy