Chemical-Shift Photoelectron Diffraction from Molecular Adsorbates

By using the chemical shift in core-level photoemission from adsorbed species, we apply the technique of energy-scan photoelectron diffraction to molecules containing nonequivalent atoms of the same element. As an example, we demonstrate the complete structural characterization of the surface acetate species on Cu{110} including independent determination of the sites of the two inequivalent carbon atoms.