Ferromagnetism in Bi- and Te-substituted MnRh

A series of experiments shows that substitution of Bi into antiferromagnetic MnRh causes this alloy to become ferromagnetic. The Curie temperature of (Mn
0.8
Bi
0.2
)Rh is 185°K and the moment is 3.5 µ
B
per formula unit. Substitution of Te instead of Bi gives similar results. This effect is consistent with a model of competitive ferromagnetic and antiferromagnetic exchange in MnRh-type compounds.