Monte Carlo simulation on nematic order of chain model using mean field potential - Order parameter in binary mixture

Monte Carlo simulations for the linear chain model composed of four success ive atoms have been performed using the method of Vacatello and lovino base d on the Flory-Ronca-Irvine mean field theory. We assumed three kinds of mo lecules having different ordering parameters and calculated each pure syste m and the binary systems of these molecules. The ordering properties for ea ch component have been determined as a function of temperature and composit ion. In the binary system consisting of substances exhibiting the nematic p hase with different order parameters, there is an approximately linear rela tionship between the order parameter and the composition. When the isotropi c molecules are mixed with the nematic substance, the order parameter decre ases with increasing mole fraction of the isotropic molecule, and the nemat ic phase changes into the isotropic phase at a certain composition.