Effects of Breit interaction on the L-2,L-3 x-ray absorption near-edge structures of 3d transition metals

Abstract

L2, 3 x-ray absorption near-edge structures (XANES) of 3d transition metal (TM) ions and their compounds are calculated by the all-electron relativistic configuration interaction method. The Breit interaction term, which is the first relativistic correction term for the electron-electron interaction in the quantum electrodynamics, is taken into account in the many-electron Hamiltonian. Then the effects on the multiplet structure for 3d TM L2, 3 XANES are investigated. The energy separation between L3 and L2 edges of theoretical spectrum decreases when the Breit interaction term is taken into account. At the final states of L2, 3 XANES, the Breit interaction energies linearly depend on the occupation number of TM 2p3/2 orbitals. They are not influenced by the valency and the crystal field. This main contribution of the Breit interaction term is, therefore, calculated to be the reduction of the separation between L3 and L2 edges, which ranges from 0.49 to 1.52 eV for Sc to Cu.