XENON ADSORPTION AS A TOOL FOR LOCAL SURFACE-STRUCTURE DETERMINATION AT IR(100) SURFACES

The adsorption of Xe at reconstructed (5 × 1), unreconstructed (1 × 1) and partially reconstructed Ir(100) surfaces has been studied using UV photoemission. It is found that the Xe induced photoemission peaks, due to emission from Xe 5p 1 2 and 5p 3 2 orbitals, are displaced by 0.3 eV comparing spectra obtained at (1 × 1) and (5 × 1) Ir(100) surfaces at saturation Xe coverage. In addition, with both surface structures the Xe induced 5p photoemission features shift to higher binding energies with increasing coverage in accord with various other Xe/metal systems. Using the Xe 5p emission as a fingerprint of the surface structure, spectra obtained at partially reconstructed Ir(100) surfaces clearly are composed of weighted contributions from Xe adsorbed at (1 × 1) and (5 × 1) surfaces, respectively. From this it can be concluded that adsorbed Xe senses the local surface structure present in patches of (1 × 1) and (5 × 1) surface geometry. © 1979.