Adsorption of O, H, OH, and H2O on Ag(100)

The adsorption of H2O and its dissociation products, O, H, and OH, on Ag(100) has been studied using an ab initio embedding method. Results at different sites (atop, bridge, and hollow) are presented. The four-fold hollow site is found to be the most stable adsorption site for O, H, and OH, and the calculated adsorption energies are 87.1, 42.7, and 76.2 kcal mol-1, respectively. The adsorption energy of water at the atop and bridge sites is almost identical with values of 11.1 and 12.0 kcal mol-1, respectively. The formation of adsorbed OH species by adsorption of water on oxygen-precovered Ag(100) is predicted to be exothermic by 36 kcal mol-1.