Regensburg 2007 – wissenschaftliches Programm

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O: Fachverband Oberflächenphysik

O 51: Metal Substrates: Adsorption III

O 51.1: Vortrag

Donnerstag, 29. März 2007, 11:15–11:30, H39

Sub-surface oxygen in Pd(100): Density-functional theory calculations — •Jörg Meyer and Karsten Reuter — Fritz-Haber-Institut, Faradayweg 4-6, D-14195 Berlin, Germany

We use density-functional theory to investigate a possible incorporation of oxygen into the Pd(100) surface at low coverages. As a first step, we compare the stability of oxygen atoms in high-symmetry sites between the first and second substrate layer with that of oxygen adsorbed on the surface. In agreement with similar results for other (100) and (111) late transition metal surfaces, sub-surface oxygen is found to be significantly less favorable. Calculated barriers show furthermore, that even if populated, sub-surface oxygen will rapidly pop up to the surface at room temperature. We discuss a possible stabilization in the sub-surface sites through nearby on-surface O atoms, and perform molecular dynamics simulations to study the accessibility of sub-surface sites in molecular beam experiments.