Cation distribution and magnetic properties of nickel–chromium ferrites NiCr<i>_x</i>Fe_2–<i>x</i>O₄ (0 ≤ <i>x</i> ≤ 1.4)

Abstract

Abstract Nickel–chromium ferrites NiCr x Fe 2– x O 4 (0 ≤ x ≤ 1.4) were studied using X‐ray diffraction, magnetization measurements and Mössbauer spectroscopy. X‐ray diffraction patterns show that all samples have cubic spinel structure. The temperature dependent magnetic measurements revealed that a magnetic compensation point appears at chromium concentration x = 0.9, 1.2 and 1.4. Moreover, it was observed that the Curie temperature T C decreases and approaches the compensation temperature T K as Cr 3+ substitution for Fe 3+ increases. The magnetization data at all concentrations are discussed in the light of Néel's molecular field model taking into account the cation distributions obtained using the analysis of Mössbauer spectra. (© 2005 WILEY‐VCH Verlag GmbH &amp; Co. KGaA, Weinheim)