Effect of the cation site occupancy on the magnetization reversal mechanism of hydrothermal barium ferrites

It has been found that when barium ferrite particles were doped with Ti and Co, the magnetization reversal mechanism of the assembly changed from mostly coherent to fully incoherent. It is assumed that the change is caused by an actual physical disruption of the superexchange interactions between the magnetic Fe/sup 3+/ ions in the S-R layers stacked along the c axis of the particles' lattice. Support of the assumption is provided by Mossbauer spectra, which show very few or no Fe/sup 3+/ ions in the bipyramidal 2b sites of the substituted materials.<
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