Regensburg 2013 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
O: Fachverband Oberflächenphysik
O 78: Surface Dynamics I
O 78.2: Vortrag
Donnerstag, 14. März 2013, 16:15–16:30, H42
Adsorption & dissociation of O2 on Ag(100) – How much do we really know? — •Vanessa Bukas, Jörg Meyer, and Karsten Reuter — Technische Universität München, Germany
Despite the considerable attention it has received over the past decades, the adsorption of oxygen on silver surfaces remains elusive of an exact microscopic description [1,2]. Connecting and elucidating past results, the present theoretical work revisits the O2-Ag(100) interaction from a density-functional theory (DFT) perspective – starting from the interpolated potential energy surface (PES) constructed by Alducin et al. within a recent dynamical study [2]. An extensive global search on this PES allows us to obtain all stable molecular adsorption configurations, corresponding vibrational modes as well as minimum energy paths leading from the former towards dissociation. While barriers of more than 1.2 eV do rationalize the low dissociative sticking probability [2], a conclusive assignment for the two species of adsorbed O2 reported by Vattuone et al. [3] cannot be reached. Re-interpolation of the existing DFT data with a different technique [1] fails to account for potential shortcomings of the PES. Aiming to go beyond the limits of the previously employed pseudo potentials [2] in future dynamical studies, we will finally present first results of highly-accurate all-electron DFT calculations using the FHI-aims code [4].
[1] I. Goikoetxea et al., New J. Phys. 14, 013050 (2012).
[2] M. Alducin et al., J. Chem. Phys. 129, 224702 (2008).
[3] L. Vattuone et al., Surf. Sci. 377, 671 (1997).
[4] V. Blum et al., Comp. Phys. Comm. 180, 2175 (2009).