Influence of substrate dynamics on CO-MgO(001) bonding--using molecular dynamics snapshots in quantum-chemical calculations.
Combined molecular dynamics (MD) and quantum mechanics (QM) calculations have been performed for CO adsorbed on MgO(001) at 50 K. The changes in the adsorption energy caused by the surface dynamics have been analyzed, and a clear correlation was found between the dynamic variation of the adsorption energy and the electrostatic field above the adsorption site. By separating the electrostatic contributions arising from the local structure at the adsorption site from those originating from the rest of the slab, a linear expression of these contributions could be fitted which closely reproduces the dynamic changes in the adsorption energy. Using this simple linear expression, the distribution of adsorption energies for CO above the Mg(2+) sites on the MgO(001) surface at 50, 80, and 150 K have been predicted.
Department of Materials Chemistry, The Angström Laboratory, Uppsala University, Box 538, S-751 21 Uppsala, Sweden.
Björn
B
Herschend
Micael
M
Baudin
Kersti
K
Hermansson