ELECTRONIC-STRUCTURE OF PYRITE-TYPE MANGANESE DISULFIDE (PMNS(2)) - AN AB-INITIO STUDY

The linear combination of atomic orbitals as implemented in the CRYSTA L95 code has been used to obtain the electronic structure of the pyrit e-type manganese disulphide in the ferromagnetic state. Calculations m ade at the unrestricted Hartree-Fock (UHF) and local density approxima tion levels show that this compound has a lager ionic character within the HF approach. The band structures obtained with both methods of ca lculation are significantly different. In particular, the valence band is mainly occupied by the p orbitals of sulfur in the UHF approach an d the compound is described as an insulator, whereas, at the LDA level , the Mn d orbitals also lie in this band and the compound then has a conductor character. [S0163-1829(98)02227-9].