Resonant x-ray diffraction study of the charge ordering in magnetite

Abstract

Powder x-ray diffraction patterns of magnetite(Fe3O4) have been recorded at 90 K, below the Verwey transition, at three wavelengths in the pre- tomid-edge region of the 7.1 keV Fe K absorption. Simultaneous fitting of these profiles hasbeen used to refine the anomalous scattering coefficients for the octahedral B site ironatoms. The refined values give direct evidence for a significant degree (46%) ofFe2+/Fe3+ charge ordering in magnetite, and provide new constraints on the number of possible chargeordered models.