A reoptimization of the five-site water potential (TIP5P) for use with Ewald sums

The five-site transferable interaction potential (TIP5P) for water [M. W. Mahoney and W. L. Jorgensen, J. Chem. Phys. 112, 8910 (2000)] is most accurate at reproducing experimental data when used with a simple spherical cutoff for the long-ranged electrostatic interactions. When used with other methods for treating long-ranged interactions, the model is considerably less accurate. With small modifications, a new TIP5P-like potential can be made which is very accurate for liquid water when used with Ewald sums, a more physical and increasingly more commonly used method for treating long-ranged electrostatic interactions. The new model demonstrates a density maximum near 4degreesC, like the TIP5P model, and otherwise is similar to the TIP5P model for thermodynamic, dielectric, and dynamical properties of liquid water over a range of temperatures and densities. An analysis of this and other commonly used water models reveals how the quadrupole moment of a model can influence the dielectric response of liquid water. (C) 2004 American Institute of Physics.