2014/05/31 by T. Ribic, E. Assmann, A. Toth +1 · 1 citation
Physics and Astronomy · #cond-mat.str-el #cond-mat.mtrl-sci
paper · pdf · doi:10.1103/physrevb.90.165105
published as Phys. Rev. B 90, 165105 (2014) · 9 pages, 3 figures, 6 tables; as published
arxiv created 2014/10/07 · arxiv updated 2014/10/09
Many-body calculations for multi-orbital systems at present typically employ Slater or Kanamori interactions which implicitly assume a full rotational invariance of the orbitals, whereas the real crystal has a lower symmetry. In cubic symmetry, the low-energy t2g orbitals have an on-site Kanamori interaction, albeit without the constraint U = U' + 2J implied by spherical symmetry (U: intra-orbital interaction, U': inter-orbital interaction, J: Hund's exchange). Using maximally localized Wannier functions we show that deviations from the standard, spherically symmetric interactions are indeed significant for 5d orbitals (∼25% for BaOsO3 ; ∼12% if screening is included), but less important for 3d orbitals (∼6% for SrVO3; ∼1% if screened).