Article,
Angular distributions in stimulated desorption: Photodesorption of ammonia from a Cu(111) surface
CHEMICAL PHYSICS LETTERS, 257 (1-2): 155-162 (July 1996)
DOI: {10.1016/0009-2614(96)00527-1}
Abstract
The angular distributions of flux and mean translational energy in
stimulated desorption contain valuable information about the influence
of substrate corrugation on the desorption dynamics. We present a simple
model which predicts angular distributions of desorbing neutrals if the
particle momentum parallel to the surface is conserved during the
desorption process. The model allows the calculation of the temperature
dependence of angular distributions and the observed decrease in
translational energy with increasing angle of desorption. For the
photostimulated desorption of NH3 from Cu(111) at two sample
temperatures our analysis shows that substrate corrugation has no
significant influence on the angular flux distributions which are
essentially broadened by thermal motions of the molecules within the
surface plane, i.e. due to the frustrated translation.
