IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Surface Science Friday Sessions
       Session SS2-FrM

Paper SS2-FrM3
Surface Temperature Effects in Molecular Beam Scattering: Inelastic State-to-state Scattering and the Dissociation of Hydrogen and Deuterium

Friday, November 2, 2001, 9:00 am, Room 121

Session: Gas-Solid Dynamics: Theory and Experiment
Presenter: S. Holloway, University of Liverpool, UK
Authors: Z. Wang, University of Texax, Austin
G.R. Darling, University of Liverpool, UK
S. Holloway, University of Liverpool, UK
Correspondent: Click to Email
We have carried out quantum mechanical wavepacket calculations on a parameterized LDA potential energy surface for the surface temperature dependence of the inelastic scattering of hydrogen and deuterium molecules from Cu(111). We find, in agreement with experimental data, that the surface temperature dependence of each cross-section invariably has an Arrhenius form with an 'activation energy' that depends upon the translational energy of the molecules. Additional calculations for the dissociation probability reveal very similar results. On the basis of the wavepacket calculations, it has been possible to develop a simple model to explain the results. The model is quite general, robust and results will be presented for vibrationally inelastic scattering and dissociative adsorption. We shall discuss exactly the origins of the Arrhenius form for a system where thermal equilibrium is never established, and the meaning of the derived "activation energy" in terms of the parameters entering into the dynamical model.