Adsorption of small molecules on the V2O5(001) surface

The adsorption of H, NH3, H2O, and NO on the (001) surface of vanadium pentoxide is studied with the semiempirical SCF MO method MSINDO. The (001) surface is modeled with H and OH saturated clusters (V2O5)(n)(H2O)(m) (n = 24-54, m = 20-40). Different adsorption sites are considered, and the effect of cluster size and surface relaxation on the calculated adsorption energies and geometries is investigated. A slight dependence on the cluster size is found for the adsorption energy, while there is a pronounced effect of surface relaxation. This is in qualitative agreement with previous theoretical studies of the V2O5(001) surface. The absolute values of the adsorption energies for most sites are comparable to the results of previous density functional theory calculations, indicating that MSINDO is a reliable tool for studies of surface properties of vanadium pentoxide. (C) 2002 Elsevier Science B.V. All rights reserved.