Magnetic and electronic structure of TlCo 2S 2

Abstract

An extensive investigation of the ferromagnetic compound TlCo 2S 2 has resulted in new information on the electronic and magnetic structure. Electronic structure calculations showed that magnetic ordering is energetically favorable with a clear driving force for ferromagnetic coupling within the cobalt layers. TlCo 2S 2 is metallic and the conductivity is due to holes in the valence band. XPS single crystal measurements did not show evidence of mixed oxidation states of cobalt. Neutron powder diffraction resulted in a ferromagnetic structure with the magnetic moment in the ab-plane. The derived magnetic moment of the cobalt atom is 0.65(2) μ B at 10 K and is in very good agreement with the value, μ sat =0.65(1) μ B at 10 K, inferred from the magnetic hysteresis curve.