INTRINSIC PART OF THE SURFACE-ENERGY FOR NEMATICS IN A PSEUDOMOLECULAR APPROACH - COMPARISON WITH EXPERIMENTAL RESULTS

The surface energy is introduced by means of a pseudo-molecular model which utilizes the Maier-Saupe approximation for the intermolecular in teraction and supposes the interaction volume of ellipsoidal shape. It is shown that the intrinsic contribution of the anisotropic part of t he surface energy depends on the eccentricity of the interaction volum e, and it is different from the form proposed by Rapini and Papoular. The theoretical predictions are compared with experimental data on the surface energy and they are shown to be of an order of magnitude whic h is compatible with the experimental results. In this way the intrins ic part of the anisotropic surface energy can never be neglected.