IR absorption spectra of liquid crystals: II. Preorientation potential barriers of the molecules from the homologous series of p-azoxyanisole in crystal, nematic crystal and isotropic phases

Abstract

The half-width temperature dependence of various IR bands from the homologous series of p-azoxyanisole in crystal, nematic crystal and isotropic liquid phases is investigated. The preorientation potential barrier U OR is determined. The dependence of U OR, on the number of carbon atoms in the alkyl chain shows an even-odd effect. A relationship between the value of U OR and mesophase stability was found.