화학공학소재연구정보센터
Journal of Chemical Physics, Vol.104, No.13, 5240-5243, 1996
On the Realism of the Re-Engineered Simple Point-Charge Water Model
The realism of the recently proposed high-temperature reparameterization of the simple point charge (SPC) water model [C. D. Berweger, W. F. van Gunsteren, and F. Muller-Plathe, Chem. Phys. Lett. 232, 429 (1995)] is tested by comparing the simulated microstructure and dielectric properties to the available experimental data. The test indicates that the new parameterization fails dramatically to describe the microstructural and dielectric properties of water at high temperature : it predicts rather strong short-range site-site pair correlations, even stronger than those for water at ambient conditions, and a threefold smaller dielectric constant. Moreover, the resulting microstructure suggests that the high-temperature force-field parameters would predict a twofold higher critical density. The failure of the high-temperature parameterization is analyzed and some suggestions on alternative choices of the target properties for the weak-coupling are discussed.