Detailed Mössbauer study of the cation distribution in CoFe2O4 ferrites

Abstract

Partially inverted (Co 0.185 Fe 0.815 )[Co 0.815 Fe 1.185 ]O 4 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 Co 2+ ions, formation of cobalt super lattice and submicron surface layer with spin pinning effects are taken into account.

Cation distribution of titanium substituted cobalt ferrites

“…3 shows a systematic linear fall in specific saturation magnetization with increasing titanium concentration. It is well established [10] in cobalt ferrite that A-B exchange interaction is predominant because nearly 20% cobalt occupies A-site. The observed decrease in magnetization in present system can be understood on the basis of Neel model [11].…”

Epitaxial integration of CoFe2O4 thin films on Si (001) surfaces using TiN buffer layers

“…For many of these applications, highly oriented growth of ferrite films is necessary. The magnetic and electronic properties of CoFe 2 O 4 are strongly influenced by its cationic arrangement [7][8][9]. In the spinel ferrites the anions form a face-centered cubic structure (fcc).…”

Magnetic properties of nanocrystalline CoFe2O4 synthesized by thermal plasma in large scale

“…where f A and f B represent the recoil-free fractions for the A and the B sites, respectively, and we assume that f A is equal to f B [20,21]. Mössbauer spectroscopic analysis showed that inversion parameter remains constant within the experimental error for all plasma power indicating no change in cation distribution with change in plasma power.…”