NMR investigations of ion distribution in real structure of manganese-zincferrites

Using the nuclear magnetic resonance, X-ray and electromagnetic methods we investigated structure and properties of the single- and polycrystalline ma nganous and manganese-zinc ferrites: MnFe2O4, Mn0.8Zn0.2Fe2O4, Mn0.6-xCuxFe 2.1O4 (0 less than or equal to x less than or equal to 0.3). The real struc ture of the manganous and manganese-zinc ferrites is found to contain simul taneously vacancies in cationic and anionic sublattices. The analysis of th e NMR spectra of Mn-55, Fe-57, Cu-63,Cu-65 and Zn-67 ions allowed us to fin d the magnetic and valence states of all ions and their distribution in the real spinel structure. It was shown that the Fe3+ paramagnetic ions, Zn2diamagnetic ions and cationic vacancies in tetrapositions are distributed s tatistically. The Mn3+ and Cu2+ Jahn-Teller ions and presumably Fe2+ in oct ahedral positions are distributed nonstatistically forming cluster-type mes oscopic inhomogeneities. The correlation between distribution of ions and v acancies in the real structure of manganese-zinc ferrites and their functio nal electromagnetic properties was found.