PERTURBATION-THEORY FOR MIXTURES OF POLAR AND NONPOLAR ANISOTROPIC MOLECULES

The perturbation theory of fluids of polar non-spherical molecules proposed recently, is extended to mixtures. In this perturbation expansion the mixture of Kihara molecules is taken as a reference; to evaluate perturbation terms resulting from the electrostatic interactions, the distribution function of the corresponding Gaussian overlap fluid is substituted for the molecular distribution function of the Kihara system. The described method is applied to several model binary systems and compared with simulation data when available. The effect of the permanent dipole moment and polarizability on excess thermodynamic functions of binary systems, formed by molecules of the same size and shape which differ in value for the permanent dipole moment and polarizability, is studied.