NEW TYPE OF MAGNETIC TRANSITION IN Mn₃ZnC

Abstract

Alloys with the approximate composition Mn 3 ZnC are known to be ferromagnetic but the saturation magnetization shows a maximum in the region of 231° K. X-Ray and neutron diffraction measurements are reported which demonstrate that at 231° K. there is a second order transition below which ordering of the manganese ions occurs, resulting in a tetragonal distortion of the normally cubic lattice and a complex magnetic structure. One possible magnetic structure is discussed. Above the transition the alloy is apparently a normal ferromagnetic substance.