Multipolar and orbital ordering in ferro-pnictides
(English)Manuscript (preprint) (Other academic)
The stability of different solutions corresponding to various arrangement of magnetic rank-4 multipoles are evaluated for the ferro-pnictides LaOFeAs, BaFe2As2 and CaFe2As2 compounds. For LaOFeAs, the ground-state solution is identiﬁed with a combination of large w4120 and w4120 multipole tensors of the magnetization density which integrates to the correct value of experimental moment. The same procedure is applied to BaFe2As2 and CaFe2 As2 where the lowest energy solution corresponds again to a combination of w4120 and w4120 multipoles, but with a magnetic moment lower than the experimental value. However, for these compounds, our calculated moment constitutes a signiﬁcant improvement over previous ab-initio calculations that largely overestimate the Fe moment. Moreover for BaFe2As2 and CaFe2As2 , in the total energy curves as function of constrained spin moment, we identify a local minima close to the experimental moment.
High temperature superconductivity, correlated electrons, electronic structure calculations
Condensed Matter Physics
Research subject Physics of Matter
IdentifiersURN: urn:nbn:se:uu:diva-132066OAI: oai:DiVA.org:uu-132066DiVA: diva2:356797