Au-induced charge redistribution on Si(1 1 1)-7 × 7 surface

We combined scanning tunneling microscope/spectroscopy studies and first-principles calculations to investigate the evolution of the electronic structures associated with the adsorption of Au on the Si(1 1 1)-7 × 7 surface. The charge transfer between the deposited Au and its adjacent Si atoms was clearly revealed by the local density of states and charge density difference. The Au-5d states are hybridized with the Si-3p states and the dangling bonds of Si atoms are saturated, which induced a reduction of empty states at about +0.4 eV and an increase of filled states with additional peaks at about −0.6 eV and −1.5 eV.