Fourth Order Interaction Effects on the Antiferromagnetic Structures. II. A Phenomenological Model for NiS₂

Abstract

Possible fourth order interactions among localized spins in an orbital-degenerate case (S>1⁄2) are discussed as an expansion from the Mott insulator limit, with reference to a model for the electronic structure of NiS₂. Then a phenomenological model to study the antiferromagnetic structure of NiS₂ is presented.