Importance of anisotropic Coulomb interactions in the electronic and magnetic properties of Mn${}_3$O${}_4$

Abstract

We report the importance of anisotropic Coulomb interactions in DFT+U calculations of the electronic and magnetic properties of Mn${}_3$O${}_4$. The effects of anisotropic interactions in Mn${}^{2+}$ and Mn${}^{3+}$ are separately examined by defining two different sets of Hubbard parameters: $U^{2+}$ and $J^{2+}$ for Mn${}^{2+}$ and $U^{3+}$ and $J^{3+}$ for Mn${}^{3+}$. The anisotropic interactions in Mn${}^{3+}$ have a significant impact on the physical properties of Mn${}_3$O${}_4$ including local magnetic moments, canted angle, spontaneous magnetic moment, and superexchange coupling, but those in Mn${}^{2+}$ do not make any noticeable difference. Weak ferromagnetic interchain superexchange, observed in experiments, is predicted only if a sizable anisotropic interaction is considered in Mn${}^{3+}$. By analyzing the eigenoccupations of the on-site Mn density matrix, we found that the spin channel involving Mn${}^{3+}$ $d_{x^2-y^2}$ orbitals, which governs the 90${}^{\circ }$ correlation superexchange, is directly controlled by the anisotropic interactions. These findings demostrate that the exchange correction $J$ for the intraorbital Coulomb potential is of critical importance for first-principles description of reduced Mn oxides containing Mn${}^{3+}$ or Mn${}^{4+}$.

References in corpus (7)

• Magnetodielectric coupling in Mn3O4
• First-Principles Studies of the Atomic, Electronic, and Magnetic Structure of a-MnO2 (Cryptomelane)
• The importance of anisotropic Coulomb interactions and exchange to the band gap and antiferromagnetism of β-MnO2 from DFT+U
• Structural change and phase coexistence upon magnetic ordering in the magnetodielectric spinel Mn${}_3$O${}_4$
• Magnon spectra and strong spin-lattice coupling in magnetically frustrated MnB2O4 (B = Mn,V): Inelastic light scattering studies
• On the derivation of the magnetocaloric properties in ferrimagnetic spinel Mn3O4
• Effects of paramagnetic fluctuations on the thermochemistry of MnO (100) surfaces in the oxygen evolution reaction

Cited by in corpus (2)

• Tunable Ferromagnetism in LaCoO3 Epitaxial Thin Films
• Controlling Projection-Space Artifacts in DFT+U via Projection-Consistent U_{eff}