The temperature variation of refractive indices (n
o,ne), birefringence (Δn
), density (ρ) and order parameter (S) of two cholesteric liquid crystals—cholesteryl benzoate and laurate are reported in the smectic, cholesteric and isotropic phases. The order parameters have been evaluated using Aver'yanov's relations. The S values determined are good agreement with NMR data.
The mean polarizabilities (
) of a few cholesteric liquid crystals have been evaluated using (i) the modified method of Lippincott-δ-function potential model and (ii) the additivity rule of bond polarizabilities. There is good agreement between the values of
calculated by these methods and experimental values, thereby suggesting the general applicability of Lippincott-δ-function potential model to liquid crystals.