Modification of the Fixman’s Analytic Function in Binary Liquid Mixtures

The mode-coupling theory of Fixman failed to explain the experimental behavior of the binary liquid mixtures at critical concentration and above critical temperature. The analytic function of Fixman’s theory was modified in order to get an agreement with the experimental behavior of the binary liquid mixtures at critical concentration and above the critical temperature. Ultrasonic absorption and velocity of some binary liquid mixtures were used to test the validity of the Modified-Fixman’s theory. It is found that the ratio of heat capacities γ_0=C_p/C_V (at constant pressure and volume) of the binary liquid mixtures is the term which plays the role to modify the Fixman’s theory to get a good agreement with the experimental behavior.