Chemisorption of atomic oxygen on silicon surface

We investigated the electronic structure of oxygen adsorbed on silicon surface in a head-on position, and showed that only the corresponding bonding structure is able to explain the features in UPS and ELS spectra that were not interpreted satisfactorily before. We also found that charge is transferred from backbonds to SiO bond and induces empty states localized between the first and second layers of the silicon surface.