Electronic structures of Ag-adsorbed Si(111) surface

Abstract

The electronic structure of the Si(111) 3 × 3 -Ag surface is investigated by the first principles DV-Xα SCC and SCM methods with the use of a model suggested by Yang et al. and an embedded model. The calculated total energy and the binding energy of the Ag 4Si 13H 16 cluster for Yang's model are lower than that for the embedded model. The variation in binding energy of the AgSi 7H 13 cluster with the Ag position has an energy minimum at the Ag position of 0.05 Å above the first Si layer which implies that the atomic geometry of Yang's model is more reasonable. The contour map of charge density distribution reveals that the binding between Ag and Si atoms is weak.