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

We present the results from investigations on a series of binary chiral-dop ant liquid-crystalline mixtures. The racemic host materials possess tilted smectic phases with varying strengths of synclinic and anticlinic ordering (SmC and SmCA phases 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 m ixtures were investigated in test cells of different thickness and the infl uence of each mixture component on the observed physical properties is disc ussed.