An examination of the five-site potential (TIP5P) for water

Abstract

Parameterization of the five-site model (TIP5P) for water [M. W. Mahoney and W. L. Jorgensen, J. Chem. Phys. 112, 8910 (2000)] has been examined by several computer simulation methods accounting properly for long-range forces. The structural and thermodynamic properties at a pressure of 1 atm over the temperature range (−25 °C,+75 °C) and the vapor–liquid coexistence have been determined. It is shown that the simple spherical cutoff method used in the original simulations to find optimized parameters of this five-site model yields results that differ from those obtained by both the Ewald summation and reaction field methods. Consequently, the pivot property to which the parameters were adjusted, the location of the density maximum at 1 atm, does not agree with experimental values. The equilibrium properties then show only a fair agreement with experimental data and are uniformly inferior to those of the four-site TIP4P water over the entire coexistence range.