Energy loss of atoms at metal surfaces due to electron-hole pair excitations: first-principles theory of "chemicurrents".
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.
Trail
J R
JR
Department of Physics, University of Bath, Bath BA2 7AY, United Kingdom. j.r.trail@bath.ac.uk
Graham
M C
MC
Bird
D M
DM
Persson
M
M
Holloway
S
S