A density functional study of CO2 adsorption on the (100) face of Cu(9,4,1) cluster model

The adsorption modes of inert CO2 on the (100) face of Cu(9,4,1) cluster model have been studies by the Slater DFT code of the Amsterdam density; functional (ADF) program. The side-on adsorption mode with near linear CO2 lying at the short bridge site has the highest binding energy of 26.31 kJ mol(-1). The binding energies of CO2 in similar geometry on the cross bridge, hollow, and on-top sites vary from 19.66 to 21.8 kJ mol(-1). The investigation also revealed that a number of CO2 bent modes with O-C-O angles equal to approximate to 150 degrees can coordinate with the surface with binding energies ranging from 9.66 to 23.56 kJ mol(-1). Further calculations indicated that to cause the CO2 molecule to bend to approximate to 150 degrees, there is negative charge transferred from the copper cluster to the CO2 molecule. (C) 1997 Elsevier Science B.V.