On magnetocrystalline anisotropy in NiZn ferrites

Investigations are made of the magnetocrystalline anisotropy of NiZn solid solutions of a Ni1–x–yFeZnyFeO4 system. Dependences of the first constant of the magneto-crystalline anisotropy, K1, on the Zn and Fe2+ contents in the specimens have been found. To explain the dependences it is assumed that the Fe2+ ions occupy both the octahedral and tetrahedral lattice sites in the ferrites containing divalent iron, and that the contributions to K1 from non-equivalent Fe ions have opposite signs: K < 0, K > 0. The comparison of the K1 data with the results for σs and NGR at Fe57 nuclei indicates the change in the degree of inversion with changing Zn content of the solid solutions.