https://doi.org/10.1140/epjb/e2013-40564-6
Regular Article
Effect of van der Waals interactions on H2 dissociation on clean and defected Ru(0001) surface
1
Lappeenranta University of Technology,
P.O. Box 20, 53851
Lappeenranta,
Finland
2
Aalto University, School of Science, Department of Applied
Physics, P.O. Box
11100, 00076
Aalto,
Finland
a
e-mail: mikko.puisto@lut.fi
Received: 12 June 2013
Received in final form: 5 August 2013
Published online: 25 September 2013
Ab initio computational methods are used to study the relevance of van der Waals interactions in the case of a hydrogen molecule adsorption on the Ru(0001) surface. In addition to the clean surface, the effects of ruthenium adatom and vacancy on the process are studied. The adsorption characteristics are analyzed in terms of two dimensional cuts of the potential energy surface (PES). Based on the earlier studies for such systems, we mostly concentrate on the trajectories where the hydrogen molecule approaches the surface in parallel orientation. The results indicate that for a clean Ru(0001) the calculations applying the non-local van der Waals potentials yield higher barriers for the dissociation of the H2 molecule. Of the high symmetry sites on Ru(0001), the top site is found to be the most reactive one. The vacancy and ruthenium adatom sites exhibit high dissociation barriers compared with the clean surface.
Key words: Computational Methods
© EDP Sciences, Società Italiana di Fisica and Springer-Verlag, 2013