Highly under-coordinated atoms at Rh surfaces: Interplay of strain and coordination effects on core level shift

Abstract

The electronic structure of highly under-coordinated Rh atoms, namely adatoms and ad-dimers, on homo-metallic surfaces has been probed by combining high-energy resolution core level photoelectron spectroscopy and density functional theory calculations. The Rh3d5/2 core level shifts are shown to be proportional to the number of Rh nearest-neighbours (n = 3, 4 and 5). A more refined analysis shows that the energy position of the different core level components is correlated with the calculated changes of the individual interatomic bond length and to the energy changes of the d-band centre, which is known to be a reliable descriptor of local chemical reactivity. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.