CATION SITE PREFERENCE AND MAGNETIC-PROPERTIES OF CO-SN-SUBSTITUTED BA FERRITE PARTICLES

The magnetic properties and the cation site preferences of Co2+ and Sn 4+ in Co-Sn-substituted barium ferrite (BaF) were investigated by magn etic measurements and Mossbauer spectroscopy. It was shown that Co2+ a nd Sn4+ cations prefer to occupy 4f(VI), 2b and 12k crystallographic s ites. The dramatic decrease in coercivity H(c) of the substituted BaF particles, with increasing substitution x from 0.2 to 1.4, could be ex plained by the Co2+ and Sn4+ preferences for 4f(VI) and 2b sites, whic h weakened the effective uniaxial anisotropy of BaF. The decrease in t he Fe3+ at 12k lattice sites was the major reason for the linear reduc tion in the specific saturation magnetization sigma(s) with increasing x. The conditions of the above Co-Sn-substituted BaF were different f rom those of Co-Ti-substituted BaF.