Detailed Mössbauer study of the cation distribution in CoFe2O4 ferrites

Abstract  Partially inverted (Co0.185Fe0.815)[Co0.815Fe1.185]O4 spinel submicron particles with spherical shape are studied at low temperature by Mössbauer spectroscopy. Canted magnetic structures are evidenced. The hyperfine magnetic field distributions P(H hf ) have been simulated by model with two polynomial cation distributions for A- and B-sites. The influence of the second nearest-neighbours and perturbation effect of the third nearest-neighbours are taken into account. The synthesized magnetic field distributions cannot fit with high precision the experimentally observed one. Better explanation is possible if clustering, predominantly occupation of some crystallographic planes with Co2 +  ions, formation of cobalt super lattice and submicron surface layer with spin pinning effects are taken into account.