  In this paper, we report on the magnetic properties of Ba2CoS3, a spin-chain
compound recently found to be the first Co2+ containing one-dimensional
sulphide to show metallic-like conductivity and negative magnetoresistance. We
carried out an in-depth experimental investigation of the local structure of
the cobalt atoms, and ab-initio calculations of the resulting electronic
configuration of Co2+. From theoretical considerations, the intra-chain
coupling was predicted to be antiferromagnetic. Experimentally, several
estimates of this magnetic coupling were derived by analysing the temperature
dependence of the magnetic susceptibility. Magnetic and heat capacity
measurements also provided evidence of a three-dimensional antiferromagnetic
ordering, a feature indicative of a noticeable inter-chain coupling in this
quasi-1D system.
