AVS 52nd International Symposium
    Surface Science Thursday Sessions
       Session SS3-ThM

Paper SS3-ThM10
Experimentally and Theoretically Determined Core-Level Shifts for Ultrathin Pd, Ag and AgPd Films on Ru(0001)

Thursday, November 3, 2005, 11:20 am, Room 203

Session: Reactivity of Bimetallic Surfaces
Presenter: J. Onsgaard, Aalborg University, Denmark
Authors: J. Onsgaard, Aalborg University, Denmark
L. Bech, Aalborg University, Denmark
W. Olovsson, Uppsala University, Sweden
I. Abrikosov, Link@um o@ping University, Sweden
Correspondent: Click to Email
Ultrathin composed metal films deposited on a relatively inert substrate are complex systems that are subject to both thin-film and surface-alloying effects. The evolution during build-up of ultrathin films of Pd and/or Ag deposited on Ru(0001) was followed by means of synchrotron-based photoelectron measurements (PES) of the valence band and of the Pd and Ag 3d5/2 core levels. Similarly, the evolution during stepwise annealing of ultrathin films of Ag and Pd deposited one-by-one on Ru(0001) was followed. LEED was applied to gain information on the atomic structure. The sample temperature was close to room temperature during data acquisition, whereas it typically was kept at ~550 K during metal exposures. Characteristic changes observed during film growth and annealing will be demonstrated. Further, experimentally obtained core level PES measurements will be compared with results of Density Functional Theory (DFT) calculations, which are based on the coherent potential approximation (CPA) and carried out within the complete screening picture, which includes both the initial and final state effects of PES.