AVS 51st International Symposium
    Surface Science Monday Sessions
       Session SS-MoP

Paper SS-MoP4
Chemical Bonding of Saturated Hydrocarbons to Metal Surfaces

Monday, November 15, 2004, 5:00 pm, Room Exhibit Hall B

Session: Poster Session
Presenter: H. Öström, Stockholm University, Sweden
Authors: H. Öström, Stockholm University, Sweden
L. Triguero, KTH syd, Sweden
M. Nyberg, Stockholm University, Sweden
H. Ogasawara, Stanford Synchrotron Radiation Laboratory
L.G.M. Pettersson, Stockholm University, Sweden
A. Nilsson, Stockholm University, Sweden
Correspondent: Click to Email
We have investigated the electronic and geometric structure of saturated hydrocarbons adsorbed on metal surfaces using x-ray absorption spectroscopy (XAS) and x-ray emission spectroscopy (XES) in combination with density functional theory (DFT) spectrum calculations. XES, which probes the occupied density of states, reveals new adsorption-induced states, which we assign to interaction between the both occupied and unoccupied CH orbitals and the metal d-band. By performing a systematic investigation of how the XA and XE spectra are influenced by different structural parameters, we conclude that the geometry is significantly distorted relative to the gas phase. The bonding to the surface leads to strengthening of CC bonds and weakening of CH bonds. Comparison between different metals shows that the position of the metal d-band is important for the bonding to the surface. These results can be useful for the understanding of the CH bond cleaving mechanism, which is important in catalysis.