A Crystallographic and Moessbauer Spectroscopic Study of BaCo_(0.5x)Zn_(0.5x)Ti_x Fe_(12-2x)O_(19) (M-Type Hexagonal Ferrite)

摘要

A series of pure polycrystalline M-type hexagonal ferrite with the formula BaCo_(0.5x)Zn_(0.5x) Ti_xFe_(12-2x)O_(19) (x = 0.0, 0.4, 0.8, 1.2, 1.6, 2.0) has been synthesized and studied by X-ray diffraction and Moessbauer spectroscopy. With increasing substitution the Moessbauer spectra change from magnetically ordered (x = 0) towards magnetically ordered with strong line broadening (x = 0.4 to 1.6) to nonmagnetic (x = 2.0), due to decreasing of Curie temperatures. Differential line broadening and relative area of components indicates that for small values of x, a substitution occurs preferentially in 4f_1 and 4f_2 sites indirectly affecting Fe in the 12k site.