Epitaxy and structure of the chloride phase formed by reaction of chlorine with Cu(100). A study by X-ray photoelectron diffraction

Chloride layers of thickness of several atomic layers were prepared by low temperature reaction of Cl-2 with a clean Cu(001) surface. The structure of the chloride layer was examined by X-ray photoelectron diffraction (XPD). The results of the comparison of experimental XPD data and calculations carried out using the single scattering cluster-spherical wave (SSC-SW) model show that the chloride grows as epitaxial fee, zincblende CuCl, with the (111) plane parallel to the substrate surface. The results also indicate that the (111) ''chlorine'' termination is the actual termination of the chloride phase, out of the two possible terminations of the polar zincblende structure.