Mixed valences in nanometric ferrites investigated by resonant powder diffraction

The dependence of the absorption‐edge position on ion valence in resonant scattering can be used to analyse the ionic composition of complex oxides. As the diffraction spectra are more sensitive to than to , the shift in associated with the valence can be used to refine the cation distribution. Below the absorption edge the shape of is quite insensitive to other site parameters. High‐angle data are important to reach significant variation of the diffraction lines. The feasibility of this method for powder materials was tested using a nanometric powder of magnetite, Fe3O4. More complex ferrites were then investigated and the results compared with neutron diffraction experiments.