Magnetic Transformation in MnBi

Abstract

Manganese bismuth loses its spontaneous magnetization very sharply at 633\ifmmode^\circ\else\textdegree\fi{}K. At the same temperature drastic changes occur in the lattice constants. Previous workers have interpreted both these phenomena as arising from a ferromagnetic-antiferromagnetic transition. The present work indicates that the phase existing above 633\ifmmode^\circ\else\textdegree\fi{}K is actually a ferromagnetic one with a Curie temperature of about 470\ifmmode^\circ\else\textdegree\fi{}K.