A Possible Model for the Weak Ferromagnetism of NiS₂

Abstract

A model is proposed to explain the weak ferromagnetism of NiS₂. A term in the free energy, allowed in the presence of the mixed spin structure of the first kind and the second kind on the fcc lattice of Ni ions, is found to lead to a canted weak ferromagnetism. Comparison of theoretical results with the experimental ones is satisfactory.