The natural line shape of the 3${\mathit{d}}_{5/2}$ bulk and surface core levels of Rh(110) and Rh(100) single crystals have been measured using synchrotron radiation. The (100) surface peak has a Lorentzian line width which is approximately 90 meV wider than that of the bulk, while for the (110) surface the difference is 80 meV. The singularity index of the bulk and the (100) and (110) surfaces are 0.21, 0.20, and 0.32, respectively. The trend in singularity index is consistent with a model in which the most open face, (110), is most atomiclike. The increased Lorentzian broadening is associated with shorter lifetimes of the core holes of the surface peaks, but the trend is not consistent with the model. © 1996 The American Physical Society.

• Received 20 June 1996

DOI:https://doi.org/10.1103/PhysRevB.54.7713