Temperature-induced surface transition in nematic liquid crystals orientedby evaporated SiOx - art. no. 021703

Temperature induced surface transitions observed in nematic liquid crystals oriented by obliquely evaporated SiOx are analyzed. It is shown that the e xperimental data can be interpreted with a theory for the thermal renormali zation of the anisotropic part of the surface energy based on the mean fiel d approximation. By assuming that the nematic scalar order parameter is giv en by the Maier-Saupe theory, the fit is obtained with only one free parame ter. The temperature behaviors of the polar and azimuthal angles are in agr eement with the proposed model over the whole temperature range.