Abstract
The coexisting densities for an ab-initio model for water have been calculated using grand canonical Monte Carlo simulations with the histogram reweighting technique. Although good agreement with experimental data is found for the radial distribution function at room temperature, the predicted critical density and temperature are well below both the experimental value as well as predictions from semi-empirical potentials. Improvement in the repulsive part of the ab-initio potential is suggested as a way to obtain better agreement with experiment.