Interfacial reconstruction in the system Pb/Ag(1 1 0)

We have examined the Pb/Ag(1 1 0) adsorption system using low energy electron diffraction (LEED) and synchrotron radiation X-ray photoemission spectroscopy (SRXPS). At a temperature of 120 K, layer-by-layer growth occurs and no superstructure is observed by LEED. On heating a two monolayer film to 230 K, or on deposition of two monolayers at 300 K temperature, a c(2 × 4) superstructure is observed. We interpret this as a reconstruction involving a (1 × 2) Ag substrate, and a buckled hexagonal overlayer of Pb. The reconstruction is unusual as it is induced at a solid–solid interface, rather than by an adsorbate at the solid–vacuum interface. Core level shifts of the Pb 5d and 4f and Ag 3d levels are also reported.