Antiferromagnetic—Ferromagnetic Transition in the Compound Mn3GaC

The compound Mn3GaC has been found to have a crystal structure of the perovskite type and a ferromagnetic Curie point of 246°±2K°. At a lower temperature, about 150°K, it exhibits a rather abrupt transition to an antiferromagnetic state. At this transition, there is a rapid decrease of lattice parameter and of resistivity with increasing temperature. The transition has been studied as a function of magnetic field up to 200 kOe while both transitions have been examined in hydrostatic pressures up to 4000 bar. From these data, the latent heat of the abrupt transition is calculated to be about 1 cal/g.