Temperature Dependence of the Anisotropy of Turbidity and Elastic Constants of Nematic Liquid Crystal Mixture E7

The three principal elastic constants, K11, K11, and K33, of the eutectic nematic liquid crystal mixture E7 have been determined as a function of temperature by following changes in the anisotropy of turbidity of a magnetically aligned specimen. The agreement with values of K22 obtained by a previous capacitance-voltage method is excellent, whereas the values of K11 and K33 derived from the absorption coefficients are systematically higher.