AN AB-INITIO HARTREE-FOCK STUDY OF THE MAGNETIC STATES OF THE POLYMORPHS OF MNS

Periodic unrestricted Hartree-Fock calculations are shown to predict t he correct low-temperature magnetic phases of alpha-MnS (AF(2)) and bo th cubic and hexagonal forms of beta-MnS (AF(3)). The high-spin insula ting nature of MnS is also correctly predicted with local moments clos e to those derived from neutron scattering factors. MnS in all its for ms is shown to be a largely ionic p-->d charge transfer system with a predominantly d(5) (L) under bar first ionized state.