Photoemission Study of U-Ge Compoundsby the Use of Synchrotron Radiation

Abstract

The photoelectron spectra of U-Ge compounds, UGe 2 , U 3 Ge 4 and U 5 Ge 3 , have been measured at room temperature for excitation photon energies from 32 to 120 eV using synchrotron radiation. The spectral distributions of the state density of the U 5 f electron and those of electrons in the states other than the U 5 f states are obtained by means of resonant photoemission. The observed profiles of the U 5 f photoelectron spectra resemble each other. They have sharp Fermi edges and the emission intensity decreases monotonically toward higher binding energy. The excitation spectra for the 5 d -5 f resonant photoemission have two peaks. One occurring at a lower excitation energy with a weaker intensity corresponds to prethreshold lines found in the case of the 4 d -4 f resonance excitation spectra of lanthanide compounds.