Bulg. J. Phys. vol.36 no.s1 (2009), pp. 39-47

Detailed Mössbauer Study of the Cation Distribution in CoFe2O4 Ferrites

V. Rusanov1, V. Gushterov1, S. Nikolov2, A.X. Trautwein3
1University of Sofia, Faculty of Physics, Department of Atomic Physics, 5 James Bourchier Blvd., 1164 Sofia, Bulgaria
2Technical University of Sofia, Department of Physics, 8 Kl. Ohridski Blvd., 1756 Sofia, Bulgaria
3Universität zu Lübeck, Institut für Physik, Ratzeburger Allee 160, D-23538 Lübeck, Germany
Abstract. Partially inverted (Co0.185Fe0.815)[Co0.815Fe1.185]O4 spinel submicron particles with spherical shape are studied at low temperature by Mössbauer spectroscopy. The hyperfine magnetic field distributions P(Hhf) have been simulated by model calculations with two polynomial cation distributions for A- and B-sites. The influence of the second nearest-neighbours and of the perturbation caused by the third nearest-neighbours are taken into account. The synthesized magnetic field distributions cannot fit with high precision the experimentally observed one. Better agreement is obtained if clustering, predominantly occupation of some crystallographic planes with Co2+ ions, and the formation of cobalt super lattice and submicron surface layer with spin pinning effects are taken into account.

Full-text: PDF

go back