First-Principles Calculation of Ligand Field Parameters for <i>L</i>-Edge Spectra of Transition Metal Sites of Arbitrary Symmetry

Abstract

Recently we have proposed a simple method for obtaining the parameters of a ligand field multiplet model for L-edge spectra calculations from density functional theory. Here we generalize the method to systems where the metal site has arbitrary point symmetry. The ligand field-induced splitting of the metal d-level becomes a hermitian matrix with cross-terms between the different d-orbitals. The anisotropy of the covalency is fully taken into account and it rescales the electron–electron interaction and the oscillator strength in an orbital-dependent way. We apply the method to polarization-dependent V L-edge spectra of vanadium pentoxide and obtain very good agreement with the experiment.

Keywords

• ligand field multiplet theory
• X-ray absorption spectra
• transition metal <i>L</i>-edge
• density functional theory
• vanadium oxide