MONTE-CARLO STUDY OF LOCAL STRUCTURES IN BENZENE-METHANOL MIXTURES

Monte Carlo(MC) calculations have been carried out for three benzene-methanol solutions within conventional NVT ensemble by the Metropolis scheme as an extension of a previous study. Altogether, seven systems have been simulated. The mole fractions of methanol in the benzene-methanol solutions studied are 0.0, 0.05, 0.10, 0.25, 0.50, 0.75 and 1.0, respectively. The MC results show the self-association of methanol, the structure of which changes from spherical at low methanol concentration to flexible chain-like and to network in more concentrated solutions. In spite of the shape change of the associating complex of methanol, the structure of the bulk benzene does not change as much up to the equimolar solution. The complex changes in the local composition ratio demonstrates the difficulties in predicting thermodynamic properties by equations of state.