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

High-resolution images of the vacuum oxide surface atomic structure of Ag111-p(4×4)-O reveal large terraces of a perfect (4×4) reconstruction. Under certain conditions, the surface Ag atoms at the interface between the reconstructed oxide layer and the underlying Ag111 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.