An ab initio study of atomic geometry, electronic states and
bonding for H2S-adsorption on III-V(110)-(1x1) surfaces
Department of Physics, University of Exeter, Stocker Road, Exeter
EX4 4QL, UK
Abstract
Ab initio calculations, based on pseudopotentials and the
density functional theory, have been made to investigate the
equilibrium atomic geometry, electronic states and bonding of the
H2S molecule on the InP(110), GaAs(110) and GaP(110)
surfaces within a dissociative adsorption model. In general the
adsorption of H2S on the three semiconductors shows similar
behaviour. The calculated average distances between the topmost InP,
GaAs and GaP layer and the sulphur atom are 1.87, 1.67, and 1.65 A,
respectively. In all the cases studied here, the fundamental band gap
is free of surface states, with an occupied surface state close to the
valence band maximum. The calculated electronic states are in
agreement with reported angle-resolved photoemission data.