A DFT study of dioxymethylene adsorption on the copper (111) surface

Quantum density functional theory (DFT) results are reported for the adsorp tion of H2CO2 on the Cu (111) metallic surface as modelled by a Cu-30 clust er. The calculations suggest that the H2CO2 species stabilises in the cross -bridge site with the two oxygen atoms located at different distances from the surface. The H2CO2 species prefers an orientation with the OCO plane no rmal to the surface. Mulliken population analysis in the adsorbed species s hows that there is charge donation from the copper surface to the double ra dical. The internal geometry of the adsorbed species is very different from that of the free molecules and this is the result of the strong interactio n with the metal surface. The bonding of this adsorbate to the copper surfa ce is essentially ionic. (C) 1999 Elsevier Science Ltd. All rights reserved .