Surface physics of thermotropic liquid crystals

Abstract

Phenomena occurring at the interface of liquid crystals with other (solid, liquid, and gaseous) phases are reviewed. The basic parameters of the macroscopic surface physics of thermotropic liquid crystals are studied: the adhesion energy, the surface order parameter, and the surface polarization; the basic methods for determining them experimentally are described. A great deal of attention is devoted to methods for obtaining a uniform orientation of liquid crystals. The role of the surface in phase transitions is analyzed in detail. The effect of the interface on the formation and structure of defects in liquid crystals is described. The role of van der Waals forces in the orientation of liquid crystals and in local Fredericks transitions is analyzed.