Unexpected 3+ valence of iron in FeO${}_2$, a geologically important material lying "in between" oxides and peroxides

Abstract

Recent discovery of pyrite FeO${}_2$, which can be an important ingredient of the Earth's lower mantle and which in particular may serve as an extra source of water in the Earth's interior, opens new perspectives for geophysics and geochemistry, but this is also an extremely interesting material from physical point of view. We found that in contrast to naive expectations Fe is nearly 3+ in this material, which strongly affects its magnetic properties and makes it qualitatively different from well known sulfide analogue - FeS${}_2$. Doping, which is most likely to occur in the Earth's mantle, makes FeO${}_2$ much more magnetic. In addition we show that unique electronic structure places FeO${}_2$ "in between" the usual dioxides and peroxides making this system interesting both for physics and solid state chemistry.

References in corpus (3)

• Ground state oxygen holes and the metal-insulator transition in the negative charge transfer rare-earth nickelates
• Metal-Insulator Transition and the Role of Electron Correlation in FeO2
• Linear-Temperature Dependence of Static Magnetic Susceptibility in LaFeAsO from Dynamical Mean-Field Theory

Cited by in corpus (11)

• Emergence of quantum critical charge and spin-state fluctuations near the pressure-induced Mott transition in MnO, FeO, CoO, and NiO
• Revealing the complex nature of bonding in binary high-pressure compound FeO${}_2$
• Electronic Spin transition in FeO${}_2$: evidence for Fe(II) with peroxide O${}_2^{2-}$
• Ordering of Fe and Zn ions and magnetic properties of FeZnMo3O8
• Hydrogenation driven formation of local magnetic moments in FeO${}_2$H${}_x$
• Contrasting Ferromagnetism in Pyrite FeS${}_2$ Induced by Chemical Doping versus Electrostatic Gating
• Raman spectroscopy of the low dimensional antiferromagnet with large Neel temperature SrRu2O6
• Multiple field-induced phases in the frustrated triangular magnet Cs${}_3$Fe${}_2$Br${}_9$
• Valence Transition Theory of the Pressure-Induced Dimensionality Crossover in Superconducting Sr${}_{14-x}$Ca${}_x$Cu${}_{24}$O${}_{41}$
• Importance of the many-body effects for structural properties of the novel iron oxide: Fe${}_2$O
• Interplay of electronic correlations and chemical bonding in FeN${}_2$ under pressure