title: Energy loss of atoms at metal surfaces due to electron-hole pair excitations: first-principles theory of "chemicurrents".
abstract: A method is presented for calculating electron-hole pair excitation due to an incident atom or molecule interacting with a metal surface. Energy loss is described using an ab initio approach that obtains a position-dependent friction coefficient for an adsorbate moving near a metal surface from a total energy pseudopotential calculation. A semiclassical forced oscillator model is constructed to describe excitation of the electron gas due to the incident molecule. This approach is applied to H and D atoms incident on a Cu(111) surface, and we obtain theoretical estimates of the "chemicurrents" measured by Nienhaus et al. [Phys. Rev. Lett. 82, 446 (1999)] for these atoms incident on the surface of a Schottky diode.
authors.affiliation: Department of Physics, University of Bath, Bath BA2 7AY, United Kingdom. j.r.trail@bath.ac.uk
authors.forename: J R
authors.initials: JR
authors.lastname: Trail
authors.forename: M C
authors.initials: MC
authors.lastname: Graham
authors.forename: D M
authors.initials: DM
authors.lastname: Bird
authors.forename: M
authors.initials: M
authors.lastname: Persson
authors.forename: S
authors.initials: S
authors.lastname: Holloway