Molecular orbital studies of the electronic structure of lanthanide and actinide complexes—III chemical bonding and satellite structure in the X-ray photoelectron spectrum of uranium dioxide

Abstract

Abstract Using the multiple scattering Xα method, molecular orbital calculations of the electronic structure of UO 2 are performed by considering a cubic (UO 8 ) 12− cluster. It is shown that the typical features of the uranium 5 f shell in such complexes are well reproduced in the calculations. The greater part of the chemical bonding in UO 2 is predicted to be due to covalent interactions between U5 f and O2 p electrons. Then, a separate SCF calculation is performed for the 4 f ionized configuration of the cluster in an attempt to understand the satellite structure observed as accompanying the 4 f photoelectron signals. The calculations suggest that the satellites originate from an interatomic shake-up process involving the predominantly O2 p and U5 f molecular orbitals.