The Low Temperature Transformation in Ferrites

The general behavior of magnetite (iron ferrite) at its low temperature transformation ($\mathrm{ca}$ 118°K) is reviewed. One of the properties which undergoes a large change is the magnetocrystalline anisotropy, which is larger in magnitude and has a lower symmetry below the transformation. The magnetic symmetry axis below the transition temperature can be predetermined by cooling a single crystal through the transition in a magnetic field, and can be changed from one cube edge to another below the transformation by means of a strong magnetic field.