Dresden 2011 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
O: Fachverband Oberflächenphysik
O 19: Metal substrates: Adsorption of O / H and inorganic molecules II
O 19.1: Vortrag
Montag, 14. März 2011, 17:15–17:30, WIL A317
Hydrogen adsorption on sulfur- and chlorine-precovered Pd(100) studied by ab initio molecular dynamics simulations — •Axel Groß — Institute of Theoretical Chemistry, Ulm University, D-89069 Ulm/Germany
The influence of coadsorbates on the adsorption properties of metal surfaces is of considerable technological and fundamental importance. For example, sulfur is well-known as a catalyst poison, i.e. its presence reduces the activity of catalysts. On the other hand, the electrochemical metal-liquid interface is typically characterized by halogen adsorption from the electrolyte. As a model system to understand the effect of such coadsorbates, the adsorption of hydrogen on sulfur- und chlorine-precovered Pd(100) has been studied by ab initio molecular dynamics simulations. The sticking probability has been determined as a function of the kinetic energy, the angle of incidence and the internal degrees of freedom of the impinging H2 molecules. The results will also be compared to previous quantum dynamical studies on a fixed substrate [1]. It will be shown that sulfur and chlorine affect the adsorption properties of Pd(100) in a rather similar way, but there are also characteristic differences.
[1] A. Groß and M. Scheffler, Phys. Rev. B 61, 8425 (2000).