Localized description of surface energy gap effects in the resonant charge exchange between atoms and surfaces

A. IGLESIAS GARCÍA; EVELINA A. GARCÍA; E. C. GOLDBERG

JOURNAL OF PHYSICS CONDENSED MATTER

IOP PUBLISHING LTD

Lugar: USA; Año: 2011 vol. 23 p. 45003 - 45003

0953-8984

The resonant charge exchange between atoms and surfaces is described by considering alocalized atomistic view of the solid within the Anderson model. The presence of a surfaceenergy gap is treated within a simplified tight-binding model of the solid, and a propercalculation of the Hamiltonian terms based on a LCAO expansion of the solid eigenstates isperformed. It is found that interference terms jointly with a surface projected gap maximum atthe  point and the Fermi level inside it, lead to hybridization widths negligible around theFermi level. This result can explain experimental observations related to long-lived adsorbatestates and anomalous neutral fractions of low energy ions in alkali/Cu(111) systems.