Magnetic Transitions and Structural Changes in Hexagonal Manganese Compounds

Abstract

The lattice parameters of the isomorphous compounds MnAs, MnSb and MnBi have been measured over a temperature range which includes the temperatures at which certain magnetic transitions occur. Characteristic changes develop near the magnetic transition temperatures and are of two kinds: (a) discontinuous changes of lattice dimensions (MnAs at 40°c, MnBi at 320°c), which are associated with magnetic transitions of the first order, (b) discontinuous changes of the temperature derivatives of the lattice parameters (MnAs at 130°c, MnSb at 320°c), associated with second-order magnetic transitions.