Imaging the Surface and the Interface Atoms of an Oxide Film onAg{111}by Scanning Tunneling Microscopy: Experiment and Theory

High-resolution images of the vacuum oxide surface atomic structure of $\mathrm{Ag}\{111\}-p(4\times 4)-\mathrm{O}$ reveal large terraces of a perfect $(4\times 4)$ reconstruction. Under certain conditions, the surface Ag atoms at the interface between the reconstructed oxide layer and the underlying $\mathrm{Ag}\{111\}$ lattice are also imaged, providing the structural registry. Scanning tunneling microscopy simulations reveal a strong sensitivity to structure and comparison with the experimental images, therefore providing an atom-by-atom model for the entire metal-oxide-vacuum structure.