Cation Distributions in Ferrospinels. Magnesium-Manganese Ferrites

Abstract

The saturation magnetization as a function of quench temperature is measured for the ferrite system ${\mathrm{Mg}}_{y}{\mathrm{Mn}}_{1\ensuremath{-}y}{\mathrm{Fe}}_{2}{\mathrm{O}}_{4}$. From these data the ionic distribution of Mg ions is evaluated and compared to the theoretical thermodynamic analysis developed in the preceding paper. The interesting quantity $\frac{\ensuremath{\partial}{u}_{1}}{\ensuremath{\partial}\ensuremath{\eta}}$, where ${u}_{1}$ is the nonthermal energy and $\ensuremath{\eta}$ is the fraction of Mg ions on $A$ sites, can be evaluated from the data only if the variation of the Debye temperature with $\ensuremath{\eta}$ can be neglected. If this assumption is made, then it is found that $\frac{\ensuremath{\partial}{u}_{1}}{\ensuremath{\partial}\ensuremath{\eta}}$ is linearly dependent on $\ensuremath{\eta}$. The lattice constant has also been determined as a function of quench temperature.