Micellar shape anisotropy and elastic constants in discotic lyotropic liquid crystals

Abstract

The elastic constants of a discotic lyotropic nematic liquid crystal are\ncalculated by means of a pseudo-molecular approach as functions of the micellar\nshape anisotropy. By assuming that the temperature dependence of the ratio of\nthe elastic constants comes from the temperature dependence of the micellar\nshape anisotropy, the theoretical predictions are connected with experimental\nmeasurements for the ratio $K_{33}/K_{11}$. This procedure permits to\ndetermine, in a phenomenological way, the temperature dependence for the ratio\nof elastic constants and for the micellar shape anisotropy near the\nnematic-isotropic transition in agreement with the experimental data.\n