Magnetic properties of the dichalcogenide FeTi 2 S 4

Conflicting results have been published on the magnetic properties of FeTi 2 S 4 . Those differences have been attributed either to the preparation methods or to the degree of order of the material. It was assumed that the magnetic moments are due to iron. We have used the magnetic properties as a mean to characterize the importance of non stoichiometry and consequently to prepare the rigorously stoichiometric compound which has well reproducible magnetic properties. We think that the properties of FeTi 2 S 4 can be explained by an ionic model in which the magnetic moments proceed not only from Fe, but also from Ti. The ionic model is consistent with the properties observed in the vicinity of FeTi 2 S 4 , and agree well with the existence of a magnetic after-effect. The paramagnetic moment can be easily explained by the existence of partially covalent bonding.