Hydrogenation-driven formation of local magnetic moments in FeO2 Hx

The electronic and magnetic properties of recently discovered important constituent of the earth's lower mantle FeO2H was investigated by means of the density functional theory combined with the dynamical mean-field theory. The addition of hydrogen to the parent FeO2 compound, which is an uncorrelated bad metal, destroys the most important ingredient of its electronic structure, namely O-O molecular orbitals. In effect, the physical properties of FeO2 and FeO2H turn out to be completely different, FeO2H is a correlated metal with a mass renormalization (m∗/m∼1.7), and the magnetic moments on Fe ions become localized with the Curie-Weiss type of uniform magnetic susceptibility. © 2018 American Physical Society