Vapor-liquid equilibrium simulations of the SCPDP model of water

Molecular simulations were carried out using the self-consistent point dipole polarizability model (SCPDP) of water in the region of vapor-liquid equilibrium. The methods of isothermal-isochoric molecular dynamics (NVT-MD) and Gibbs ensemble Monte Carlo (GEMC) were employed to calculate orthobaric densities and vapor pressures; NVT-MD also yields surface tensions and interface thickness. Agreement was found between the two methods, particularly at lower temperatures, but compared with experimental results, this model over-predicts vapor pressures and densities, and under-predicts the liquid density, surface tension, and interface thickness. The interface thickness predicted by the SCPDP model showed better agreement with experimental results than a simpler extended point charge model (SPC/E). (C) 2002 Elsevier Science B.V. All rights reserved.