XPS and STM studies of pseudo-AgX monolayers organized on Ag(111) and Au/Ag(111) surfaces

Simple and well-defined model AgX surfaces are useful to illuminate a variety of surface-related phenomena associated with AgX microcrystals in a different perspective with fewer experimental impediments. From this viewpoint, we discuss a couple of pseudo-AgX monolayers that can be organized on a highly planar sputter-grown Ag(111) or ultrathin-Au-covered Ag(111) film. The monolayer structures have been satisfactorily characterized by combination of XPS and STM methods. In particular, the monolayer AgX formed on Au/Ag(111) proved to have an almost identical structure with the bilayer AgX(111) atomic configuration, thus serving as a superior monolayer model of AgX or pseudo 2D ionic crystal for deeper understanding of the processes involving the AgX surfaces.