MAGNETIC-STRUCTURE OF HEXAGONAL FERRITES STUDIED BY MOSSBAUER-SPECTROSCOPY

Hexagonal Ba-ferrites of M-type (BaFe12O19) and W-type (BaMe22+Fe163+O 27, Me-divalent cation) are promising materials for perpendicular magn etic recording. For this purpose it is desirable that their high uniax ial anisotropy be adjustable according to the specific requirements. S ubstitution of Co2+ for Fe2+/3+ cations usually decreases the magnitud e of the uniaxial anisotropy and may be used to this end. In this work the influence of Co2+ content on the details of magnetic structure of Ba-hexaferrites is studied. Mossbauer spectra of Fe-57 in single crys tals of BaFe12-2xCox2+Tix4+O19 and Ba(Fe2-xCox)2+Fe36O27 were measured at 293K. The dependence of the canting of magnetic moments on the con centration of Co was determined from the relative intensities of Mossb auer lines in the Zeeman nuclear multiplet and compared with the resul ts deduced from the magnetic measurements.