Note on the Magnetic Properties of the FeSn System

The ferromagnetic properties of the FeSn system are interpreted as an imperfectly compensated antiferromagnetism or ferromagnetism as called by L. Néel. A special case of n = 1, namely the substance FeS1.00 is regarded as an antiferromagnetic material. In FeSn, Fe3+ ions appear when n > 1, and its ferromagnetism is explained by assuming that these Fe3+ ions are preferably situated on only one of the two sublattices which correspond to + and - spin orientations respectively.