Variational quantum Monte-Carlo method in surface physics

The role of the variational quantum Monte-Carlo method for homogeneous systems and bulk material, on one hand, and finite aggregates like molecules, on the other, is now well established, mainly for the determination of ground state properties. It has been recently shown that it may be also used in surface investigations. Furthermore, dynamic behavior seems to be accessible, too, in view of the numerical resolution currently achieved. This applies also to surface dynamics. Considering the still smaller energy scales as represented by the electron-phonon interaction represents the actual borderline of accessible resolution. Nevertheless, localized electronic excitations could be investigated in bulk solids in order to yield the changes in excitation energy induced by a deformation, which shows thus a possible access to the deformation potentials. (C) 2003 Elsevier Ltd. All rights reserved.