Magnetic properties of ordered and disordered spinel-phase ferrimagnets

In spinel-phase ferrimagnets, disorder in the cation distribution between o ctahedral and tetrahedral sites can influence such fundamental magnetic pro perties as saturation magnetization, exchange coupling, and ferrimagnetic o rdering temperatures. Given the sensitivity of magnetic properties to struc ture, it has been suggested that magnetic properties may be used as a probe of disorder in ferrimagnetic spinels. In this article, we review the funda mentals of the magnetic properties of spinel ferrites, including the intere sting manifestation of noncollinear spin structures in Yafet-Kittel triangu lar spin configurations. This is followed by description of some experiment al observations on the structure and magnetic properties of (MnxAl1-x)(3)O- 4 spinels and hausmannites, which exhibit Yafet-Kittel-type ordering in the ir spin structures.