title: Ab initio modelling of magnetic anisotropy in Sr3NiPtO6.
abstract: First principles calculations in the framework of Density Functional Theory (DFT) and wavefunction-based correlated methods have been performed to investigate in detail the magnetic anisotropy in Sr3NiPtO6. This material is known for the easy-plane anisotropy with a large anisotropy constant of about 7.5-9.3 meV. We find that by properly choosing the onsite Coulomb repulsion and exchange parameters, DFT can correctly explain the easy-plane magnetocrystalline anisotropy of the material, but the magnitude of the anisotropy constant is underestimated. On the other hand, a quantitative agreement with respect to experiments, both in the magnitude and direction of the magnetic anisotropy, can be recovered by using the wavefunction-based approach which is able to fully describe the multiplet physics. We also show that the presence of structural distortions of the local NiO6 coordination is crucial for stabilizing the magnetic anisotropy in this compound.
authors.affiliation: Consiglio Nazionale delle Ricerche - CNR-SPIN, I-66100 Chieti, Italy. a.m.t.pradipto@gmail.com silvia.picozzi@spin.cnr.it.
authors.forename: A-M
authors.initials: AM
authors.lastname: Pradipto
authors.affiliation: Zernike Institute for Advanced Materials, University of Groningen, 9747 AG Groningen, The Netherlands. r.broer@rug.nl.
authors.forename: R
authors.initials: R
authors.lastname: Broer
authors.affiliation: Consiglio Nazionale delle Ricerche - CNR-SPIN, I-66100 Chieti, Italy. a.m.t.pradipto@gmail.com silvia.picozzi@spin.cnr.it.
authors.forename: S
authors.initials: S
authors.lastname: Picozzi