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We applied the self-consistent polarization density functional theory (SCP-DFT) to water. SCP-DFT requires only minimal parametrization, self-consistently includes the dispersion interaction neglected by standard DFT functionals, and has a cost similar to standard DFT despite its improved performance. Compared to the DFT functionals BLYP and BLYP-D (where the latter contains a simple dispersion correction), SCP-DFT yields interaction energies per molecule and harmonic frequencies of clusters in better agreement with experiment, with errors in the former of only a few tenths of a kcal/mol. BLYP and BLYP-D underbind and overbind the clusters, respectively, by up to about 1 kcal/mol. For liquid water, both BLYP and SCP-DFT predict radial distribution functions that are similar and overstructured compared to experiment. However, SCP-DFT improves over BLYP in predicting the experimental enthalpy of vaporization. A decomposition of the dimer interaction energy attempts to rationalize the performance of SCP-DFT. The SCP-DFT approach holds promise as an efficient and accurate method for describing large hydrogen-bonded systems, and has the potential to model complex systems with minimal parametrization. [ABSTRACT FROM AUTHOR]

We have applied an efficient electronic structure approach, the semiempirical self-consistent polarization neglect of diatomic differential overlap (SCP-NDDO) method, previously parametrized to reproduce properties of water clusters by Chang, Schenter, and Garrett [J. Chem. Phys. 2008, 128, 164111] and now implemented in the CP2K package, to model ambient liquid water at 300 K (both the bulk and the liquid-vapor interface) and cubic ice at 15 and 250 K. The SCP-NDDO potential retains its transferability and good performance across the full range of conditions encountered in the clusters and the bulk phases of water. In particular, we obtain good results for the density, radial distribution functions, enthalpy of vaporization, self-diffusion coefficient, molecular dipole moment distribution, and hydrogen bond populations, in comparison to experimental measurements. [ABSTRACT FROM AUTHOR]