NGR study of electron irradiation effect of manganese-zinc ferrospinel

To study the possibilities of obtaining direct information on the mechanisms of radiation effect on magnetic materials, the N.G.R. spectra of Mnsub(0.14)Znsub(0.15)Fesub(2.71)Osub(4) ferrospinel irradiated with 3 MeV electrons at a doze of 2.8x1017 e/cm2 are measured. Irradiation and measurements are performed at the liquid nitrogen temperature. The spectra have been measured before irradiation after irradiation and following annealing at the room temperature for 24 h using the Moessbauer 57Fe isotope. It is established that after irradiation the share of Fe2+ ions increases most evidently in tetrasublattice (from 6.7 to 8.1%), after annealing their share decreases down to 7.0%, i.e. to the value close to the initial one before irradiation. It is supposed that there is the alteration of valency of Fe ions, but not the cation redistribution over sublattices