UC Irvine

X-ray photoemission and bremsstrahlung isochromat spectroscopies have been used to probe the occupied and unoccupied states of UBe13. Between two and three electrons are found to populate the tail of a surprisingly broad 5f band ( 5 eV) of extended states. With our resolution (0.5 eV) it is not possible to observe directly at the Fermi energy any peculiarity of the density of states explaining the extraordinary properties of this compound. However, the drastic differences between the core-level spectra of U and Be indicate that the 5f states remain essentially confined around the U atoms and are only weakly hybridized with the sp-band states originating from the Be atoms. © 1984 The American Physical Society.