MOLECULAR-ORBITAL STUDIES OF THE ELECTRONIC-STRUCTURE OF LANTHANIDE AND ACTINIDE COMPLEXES .3. CHEMICAL BONDING AND SATELLITE STRUCTURE IN THE X-RAY PHOTOELECTRON-SPECTRUM OF URANIUM-DIOXIDE

Using the multiple scattering Xα method, molecular orbital calculations of the electronic structure of UO2 are performed by considering a cubic (UO8)12- cluster. It is shown that the typical features of the uranium 5f shell in such complexes are well reproduced in the calculations. The greater part of the chemical bonding in UO2 is predicted to be due to covalent interactions between U5f and O2p electrons. Then, a separate SCF calculation is performed for the 4f ionized configuration of the cluster in an attempt to understand the satellite structure observed as accompanying the 4f photoelectron signals. The calculations suggest that the satellites originate from an interatomic shake-up process involving the predominantly O2p and U5f molecular orbitals. © 1979.