Resonant “Forbidden” Reflections in Magnetite

Abstract

Resonant x-ray scattering was used to investigate electronic fluctuations of the octahedral iron atoms in magnetite. We measured the (002) and (006) “forbidden” x-ray diffraction reflections permitted by the anisotropy of the iron anomalous scattering factor. The energy and azimuthal angle dependencies of these reflections, and the polarization analysis, are shown and discussed. The results clearly show $p$ and $d$ iron empty states ordering in magnetite at room temperature. Moreover, the octahedral iron atoms are electronically equivalent in a time scale lower than ${10}^{-16\mathrm{}}\sec$. Therefore, magnetite should be considered as an itinerant magnet and not as a fluctuating mixed valence material.