Structural and electronic properties of Au onTiO2(110)

The structure and electronic properties of 1-ML Au supported on ${\mathrm{TiO}}_{2}(110)$ have been theoretically investigated using the full potential linearized augmented plane-wave method. Based on total-energy and atomic-force calculations, the preferential adsorption site for the Au adatom is predicted to be the atop site above the fivefold surface Ti atom, with a bond length of ${d}_{\mathrm{A}\mathrm{u}\ensuremath{-}\mathrm{T}\mathrm{i}}=2.66\AA{}$ and an adsorption energy of -1.49 eV per adatom. The adsorption of Au enhances the binding energies of the valence bands and core levels of the surface Ti and O atoms, the Au d bands are destabilized with metallic gap states appearing near the Fermi level. This Au-substrate interaction leads to a more active Au site for the ${\mathrm{A}\mathrm{u}/\mathrm{T}\mathrm{i}\mathrm{O}}_{2}(110)$ system compared to the Au(001) surface, in agreement with recent experimental observations.