Cation distribution and intrinsic magnetic properties of Co-Ti-doped M-type barium ferrite

Abstract

The structural and magnetic properties of BaFe12−2x Co x Ti x O19 (0≤x≤1.0) M‐type bariumferrite have been investigated by means of neutronpowderdiffraction and high‐field magnetization measurements. The cationic distribution and magnetic moments of the five different metallic sublattices are determined and compared to the experimental saturation magnetization. It is found that about 50% of Co ions occupy tetrahedral sites, thus being ineffective in the reduction of the uniaxial magnetic anisotropy, while Ti ions prefer the 4f VI octahedral sites. All in all, a clear hierarchy of sublattice preferences is defined. Although the collinearity of the magnetic structure is progressively broken, mainly above x≊0.7, the overall behavior remains ferrimagnetic. The strong local spin canting is tentatively attributed to the localization of diamagnetic Ti ions in the 4f VI octahedral sites.