Abstract:
Using Mössbauer spectroscopy, magnetometry and X-ray diffraction, we have studied the BaFe$_{12-x}$Y$_{x}$Î$_{19}$ hexaferrite (0.1 $\le x \le$ 1.2). The low isomorphic capacitance of hexaferrite is shown, which leads to phase separation with the formation of ÂàFe$_{2}$O$_{4}$ and Y$_{3}$Fe$_{5}$O$_{12}$ for $x$ = 0.6. Mössbauer spectroscopy data have shown that, in the studied range of substitutions, Y$^{3+}$ ions enter the 12$k$ position with the formation of a nonequivalent 12$k'$ position due to the breaking of two Fe(12$k$)–O–Fe(12$k$) magnetic bonds in the 12$k$ octahedron triad with their replacement by Fe(12$k$)–O–Y (12$k$). The BaFe$_{12-x}$Y$_{x}$Î$_{19}$ hexaferrite has been shown to be less magnetically hard than BaFe$_{12-x}$Y$_{x}$Î$_{19}$.