GIBBS ENSEMBLE MONTE-CARLO SIMULATION OF THE PROPERTIES OF WATER WITHA FLUCTUATING CHARGES MODEL

A Gibbs ensemble Monte Carlo calculation of the properties of water us ing the four point transferable intermolecular potential with fluctuat ing charges model (TIP4Pfq) is presented. The model yields very good r esults for the thermodynamic properties, comparable with the ones obta ined with fixed charges models and with the experimental data. Remarka ble results for the liquid phase chemical potential at room temperatur e are obtained. The dielectric constant calculation is improved with r espect to the model with fixed charges, and gives similar results when compared with a molecular dynamics simulation for the same water mode l. The intermolecular potential model used here seems to be a promisin g one for studying the properties of aqueous solutions, where the diel ectric behavior of the solvent makes a direct and substantial contribu tion to the solution properties. (C) 1997 American Institute of Physic s.