Volume 80, Number 5, December 2007
Article Number 53002
Number of page(s) 6
Section Atomic, Molecular and Optical Physics
Published online 01 November 2007
EPL, 80 (2007) 53002
DOI: 10.1209/0295-5075/80/53002

Relevant effects of localized atomic interactions and surface density of states on charge transfer in ion-surface collisions

F. Bonetto1, M. A. Romero1, E. A. García1, R. Vidal1, J. Ferrón1, 2 and E. C. Goldberg1, 2

1  Instituto de Desarrollo Tecnológico para la Industria Química, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Güemes 3450 CC 91, S3000GLN Santa Fé, Argentina
2  Departamento de Ingeniería de Materiales, Facultad de Ingeniería Química, Universidad Nacional del Litoral - Santa Fé, Argentina

received 9 May 2007; accepted in final form 10 October 2007; published December 2007
published online 1 November 2007

Through a time-dependent quantum-mechanical calculation of the H+ scattering by a highly oriented pyrolitic graphite (HOPG) surface, we are able to satisfactorily reproduce the interesting features we observed in ion scattering experiments in H+/HOPG system. We found that the combined effects of the semimetal character of HOPG together with the localized nature of the carbon atom states primarily determine the angular dependence and the magnitude of the ion fractions for large outgoing angles. The spin fluctuation effects (not considered in the present calculation) are discussed as one of the the main causes of the disagreement between the spinless theory results and the experiments for small exit angles.

34.50.Dy - Interactions of atoms and molecules with surfaces; photon and electron emission; neutralization of ions.
34.70.+e - Charge transfer.
81.05.Uw - Carbon, diamond, graphite.

© Europhysics Letters Association 2007