The electronic band structure of CoS₂

Abstract

Angle-resolved and energy-dependent photoemission was used to study the band structure of paramagnetic CoS 2 from high-quality single-crystal samples.A strongly dispersing hybridized Co-S band is identifi ed along the Γ-X line.Fermi level crossings are also analyzed along this line, and the results are interpreted using band structure calculations.The Fermi level crossings are very sensitive to the separation in the S-S dimer, and it is suggested that the half-metallic gap in CoS 2 may be controlled by the bondingantibonding splitting in this dimer, rather than by exchange splitting on the Co atoms.