Abrupt Magnetic Transition in MnSn2

The magnetic susceptibility and the electrical resistivity of the intermetallic compound Mn${\mathrm{Sn}}_2$ are found to decrease precipitously as the temperature is lowered through 73°K. Both these abrupt changes exhibit a small temperature hysteresis and are highly suggestive of a first-order transition. From 73°K down to 4.2°K, the susceptibility is essentially constant; above 73°K, the susceptibility rises slowly to a maximum (at 86°K) and then decreases in a manner consistent with the Curie-Weiss relation. It is tentatively concluded that the abrupt transition at 73°K involves only a partial disordering of an antiferromagnetic state.