Stress Dependence and the Latent Heat of the Morin Transition inFe2O3

Existing data on the magnetoelastic interaction, elastic constants, and magnetic anisotropy are used to calculate, as a function of temperature, the value of hydrostatic pressure or uniaxial stress required to induce spin flop in ${\mathrm{Fe}}_2$ ${\mathrm{O}}_3$. The results are in good qualitative agreement and fair quantitative agreement with existing data. The latent heat of the Morin transition is also calculated using these data, and the result suggests that the Morin transition is driven by an entropy difference.