Site Preference Studies for the TiMn and TiCo Substituted Ba Hexagonal Ferrites by Means of X-Ray Diffraction and Absorption Measurement.

抄録

The cation distribution of M-type BaFe₁₂O₁₉ hexagonal ferrite with partial substitution (Ti⁴⁺ M²⁺)³⁺ [M=Mn, Co] for Fe³⁺ have been investigated by using x-ray powder diffraction and XAFS measurement. The frequency dependence of microwave absorption and magnetic permeability were explained by the replacement of Fe³⁺ ions in the 2b, 4f₁ and 4f₂ sites for Ti⁴⁺ substitution. EXAFS studies showed that the site preference of transition metals in Ba(Ti_0.5 M_0.5)_x,Fe_12-xO₁₉ (x=1.0, 2.0 3.0, 4.0, 5.0) for M=Mn have same residual distribution functions for M=Co. However, the electronic states boundary of Mn ion in Mn-Ti substitution system was found by XANES spectra of Mn K-edge.