Oxygen magnetic polarization, nodes in spin density, and zigzag spin order in oxides

Abstract

Recent DFT calculations for Ba2CoO4 (BCO) and neutron scattering experiments for SrRuO3 (SRO) have shown that oxygen develops a magnetic polarization. Moreover, DFT calculations for these compounds also unveiled unexpected nodes in the spin density, both along Co-O and Ru-O. For BCO, the overall antiferromagnetic state in its triangular lattice contains unusual zigzag spin patterns. Here, using simple model calculations supplemented by DFT we explain and extend these results. We predict that ligands that in principle should be spinless, such as O${}^{2-}$, will develop a net polarization when they act as electronic bridges between transition metal (TM) spins ferromagnetically ordered, regardless of the number of intermediate ligand atoms. The reason is the hybridization between atoms and mobility of the electrons with spins opposite to those of the closest TM atoms. Moreover, for bonds with TMs antiferromagnetically ordered, counterintuitively our calculations show that oxygens should also have a net magnetization for the super-super-exchange cases TM-O-O-TM while for only one oxygen, as in Cu-O-Cu, the O-polarization should cancel. Our simple model also allows us to explain the presence of nodes based on the antibonding character of the dominant singly occupied molecular orbitals along the TM-O bonds. Finally, the zigzag pattern order becomes the ground state mainly due to the influence of the Hubbard $U$, that creates the moments, in combination with a robust easy-axis anisotropy that suppresses the competing 120${}^{\circ }$ degree antiferromagnetic order of a triangular lattice. Our predictions are generic and should be applicable to any other compound with characteristics similar to those of BCO and SRO.

arXiv comment15 pages, 17 figures

References in corpus (31)

• Restoring the density-gradient expansion for exchange in solids and surfaces
• Generalized gradient approximation for solids and their surfaces
• Maximally-localized generalized Wannier functions for composite energy bands
• Wannier90: A Tool for Obtaining Maximally-Localised Wannier Functions
• Colossal Magnetoresistant Materials: The Key Role of Phase Separation
• Correlated Electrons in High Temperature Superconductors
• A Common Thread: the pairing interaction for the unconventional superconductors
• Theory of Intertwined Orders in High Temperature Superconductors
• Proximate Kitaev Quantum Spin Liquid Behaviour in α-RuCl${}_3$
• Magnetism and its microscopic origin in iron-based high-temperature superconductors
• Scattering Continuum and Possible Fractionalized Excitations in $\alpha$-RuCl${}_3$
• Covalent bonding and magnetism in cuprates
• Frustrated Dipole Order Induces Noncollinear Proper Ferrielectricity in Two Dimensions
• Similarities and differences between nickelate and cuprate films grown on a SrTiO${}_3$ substrate
• Magnetic order and electronic structure of 5d3 double perovskite Sr2ScOsO6
• Origins Vs. fingerprints of the Jahn-Teller effect in d-electron ABX${}_3$ perovskites
• Testing the Monte Carlo - Mean Field approximation in the one-band Hubbard model
• Novel Magnetic Block States in Low-Dimensional Iron-Based Superconductors
• Fingerprints of an Exotic Orbital-Selective Mott Phase in the Block Magnetic State of BaFe${}_2$Se${}_3$ Ladders
• Semiclassical dynamics of spin density waves
• Anomalous spin density distribution on oxygen and Ru in Ca${}_{1.5}$Sr${}_{0.5}$RuO${}_4$: A polarised neutron diffraction study
• Peierls transition, ferroelectricity, and spin-singlet formation in the monolayer VOI${}_2$
• Oxygen Moment Formation and Canting in Li2CuO2
• Block-spiral magnetism: An exotic type of frustrated order
• Iron telluride ladder compounds: Predicting the structural and magnetic properties of BaFe${}_2$Te${}_3$
• Origin of the Magnetic and Orbital ordering in $\alpha$-Sr${}_2$CrO${}_4$
• Magnetization-density distribution in the metallic ferromagnet SrRuO3 determined by polarized neutron diffraction
• Block orbital-selective Mott insulators: a spin excitation analysis
• Weakly coupled alternating $S=1/2$ chains in the distorted honeycomb lattice compound Na${}_2$Cu${}_2$TeO${}_6$
• Magnetization density distribution of Sr${}_2$IrO${}_4$: Deviation from a local $j_{\text{eff}}=1/2$ picture
• Properties of La${}_{0.7}$Ca${}_{0.3}$MnO${}_3$ Under Extreme Tensile Strain

Cited by in corpus (7)

• Orbital-selective Peierls phase in the metallic dimerized chain MoOCl${}_2$
• Origin of insulating ferromagnetism in iron oxychalcogenide Ce${}_2$O${}_2$FeSe${}_2$
• Magnetic states of quasi-one-dimensional iron chalcogenide Ba${}_2$FeS${}_3$
• Prediction of orbital selective Mott phases and block magnetic states in the quasi-one-dimensional iron chain Ce${}_2$O${}_2$FeSe${}_2$ under hole and electron doping
• Strongly anisotropic electronic and magnetic structures in oxide dichlorides RuOCl${}_2$ and OsOCl${}_2$
• Electronic structure, magnetic properties and pairing tendencies of the copper-based honeycomb lattice Na${}_2$Cu${}_2$TeO${}_6$
• Frustrated network of indirect exchange paths between tetrahedrally coordinated Co in Ba2CoO4