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arXiv · 2104.10090

Ab initio ligand field approach to determine electronic multiplet properties

R. O. Kuzian·O. Janson·A. Savoyant·Jeroen van den Brink·R. Hayn
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Abstract

A method is developed to calculate the ligand field (LF) parameters and the multiplet spectra of local magnetic centers with open $d$- and $f$-shells in solids in a parameter-free way. This method proceeds from density functional theory and employs Wannier projections of nonmagnetic band structures onto local $d$- or $f$-orbitals. Energies of multiplets and optical, as well as X-ray spectra are determined by exact numerical diagonalization of a local Hamiltonian describing Coulomb, LF, and spin-orbit interactions. The method is tested for several 3$d$- and 5$f$-compounds for which the LF parameters and multiplet spectra are experimentally well known. In this way, we obtain good agreement with experiment for La$_2$NiO$_4$, CaCuO$_2$, Li$_2$CuO$_2$, ZnO:Co, and UO$_2$.

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R. O. Kuzian, O. Janson, A. Savoyant, Jeroen van den Brink, R. Hayn. 2021-04-20. Ab initio ligand field approach to determine electronic multiplet properties. https://doi.org/10.1103/physrevb.104.085154

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