Density functional theory was used to investigate the adsorption and diffusion of H2O on Al{100}. The favored adsorption site for H2O was the on-top site with a binding energy of about 0.35eV. The H2O bonded only very weakly at bridge sites, and did not adsorb at four-fold hollow sites. The activation energies for H2O diffusion depended upon the specific orientation, of the H2O molecule upon the surface, and ranged from 0.307 to 0.327eV. It was shown that the barriers to H2O diffusion were always higher than the difference in adsorption energies between H2O at the most stable (on-top) and next most stable (bridge) adsorption sites.

First-Principles Study of H2O Diffusion on a Metal Surface - H2O on Al{100}. A.Michaelides, V.A.Ranea, P.L.de Andres, D.A.King: Physical Review B, 2004, 69[7], 075409 (4pp)