ELECTRONIC-STRUCTURE, BIS, CORE-LEVEL XPS AND XAS IN CEPD7 - EXPERIMENTAL AND THEORETICAL-STUDIES

The electronic structure of CePd7 is studied using various spectroscop ic techniques (BIS, 3d/XPS and 2p/XAS). The strong delocalization of t he Ce 4f electrons, previously suggested by low-temperature specific h eat and magnetic susceptibility measurements, is consistent with the s pectra we present here. A standard LMTO band structure calculation is performed in the case of CePd7 and its-reference compound YPd7. The ba nds thus determined, especially the last valence and first conduction bands, mostly arising from Pd 4d and Ce 4f states, are actually hybrid ized; they provide a good description of the density of states at the Fermi level and a qualitative agreement with Bis spectra. Furthermore the occurrence of satellites in core-level spectra indicates a fairly strongly correlated nature of the 4f states in CePd7. In the next step , the information contained in the LmTo density of states is used to b uild an impurity Anderson Hamiltonian which incorporates the various C oulomb interactions necessary to analyse the above-mentioned spectrosc opic processes within a single set of parameter values for CePd7. Limi ts and relevance of both theoretical models are discussed.