Journal of Physical Chemistry B, Vol.115, No.30, 9421-9430, 2011
Prediction of the Temperature Dependence of the Surface Tension Of SO2, N-2, O-2, and Ar by Monte Carlo Molecular Simulations
We report Monte Carlo simulations of the liquid-vapor interface of SO2, O-2, N-2, and Ar to reproduce the dependence of the surface tension with the temperature. Whereas the coexisting densities, critical temperature, density, and pressure are very well reproduced by the two-phase simulations showing the same accuracy as the calculations performed using the Gibbs ensemble Monte Carlo technique (GEMC), the performance of the prediction of the variation of the surface tension with the temperature depends on the magnitude of the electrostatic and repulsive-dispersive interactions. The surface tension of SO2 is very well reproduced, whereas the prediction of this property is less satisfactory for O-2 and N-2, for which the average intermolecular electrostatic interactions are several orders smaller than the dispersion interactions. For argon, we observe significant deviations from experiments. The representation of the surface tension of argon in reduced units shows that our calculations are in line with the existing surface tensions of the Lennard-Jones fluid in the literature. This underlines the difficulty of reproducing the temperature dependence of the surface tension of argon with interactions only modeled by the Lennard-Jones pair potential.