Direction of the Magnetic Easy Axis inγ′-Fe4N

The direction of the easy axis of magnetization in ${\gamma }^{\prime }$ -${\mathrm{Fe}}_4$N has been determined by detailed analysis of certain peaks in the Mössbauer spectrum of a powdered sample in an applied magnetic field. The analysis indicates the magnetic-easy-axis direction to be along $〈100〉$. The electric field gradient at the face-centered Fe atoms is calculated to be - 7.0×${10}^{14}$ esu/${\mathrm{cm}}^3$.