Investigation of the indices of refraction near the smectic-A—smectic-Ctransition: Orientational order

Abstract
The results of direct measurements of the principal indices of refraction in the smectic-A and smectic-C phases of two homologous liquid crystals are reported. These results are compared qualitatively with the orientational model of Straley and with a model based on anisotropic nematic fluctuations due to coupling between orientational and translational order.