Molecular Theory on Liquid Crystalline Mixtures

Abstract

We studied theoretically liquid crystalline order of mixtures of rod-like and disk-like molecules by using simple molecule model and mean field approximation. We found in the mixtures two types of the nematic phase, optically positive and negative, because of the differences of interaction potential between the different kind of molecules and between the same kinds. Calculating the nematic-isotropic phase transition temperature, transition entropy and orientational order parameter as functions of the composition, we found that the 1st order phase transitions between the different types of the nematic phase can occur due to the changes of temperature and composition.