IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Surface Science Tuesday Sessions
       Session SS3-TuP

Paper SS3-TuP19
Adsorbate Induced Electronic Relaxation at Transition Metal > Surfaces

Tuesday, October 30, 2001, 5:30 pm, Room 134/135

Session: Adsorption/Desorption Poster Session
Presenter: G. Fahsold, Universität Heidelberg, Germany
Authors: G. Fahsold, Universität Heidelberg, Germany
A. Priebe, Universität Heidelberg, Germany
M. Sinther, Universität Heidelberg, Germany
A. Pucci, Universität Heidelberg, Germany
Correspondent: Click to Email
We investigate the relaxation of electrons at transition metal surfaces by means of IR-spectroscopy. The adsorbate induced relaxation of electrons is responsible for the DC-resistivity of metal thin films, it is connected to the damping of adsorbate motion, and it contributes to enhancement effects observed in adsorbate vibrational spectroscopy. We measured the contribution of adsorbates (CO, O) to the relaxation of electrons at iron and copper surfaces by observing adsorbate induced broadband changes, firstly, in the IR-reflectivity from thick (opague) epitaxial films and, secondly, in the IR-transmission through ultrathin (< 5 nm) smooth epitaxial films. The higher (compared to IRAS measurements) sensitivity for adsorbate resistivity in IR-transmission is well demonstrated by our experimental results. We understand our results on the basis of a proper description of the optical properties of bulk metals and metal thin films. The talk will focus on the importance of the inclusion of non free-electron-like properties for calculating both the magnitude, the sign, and the spectral shape of adsorbate induced broadband effects.