The iron electronic characteristics and the crystal dimensionality of the phases FexTiSe2 (x = 0.25, 0.38, 0.50)

The crystallographically ordered Fe x TiSe 2 compounds ( x = 0.25, 0.38, and 0.50) have been investigated as a function of temperature using Mossbauer spectroscopy, susceptibility measurements, and X-ray diffraction. It is found that the coupling between the iron- d localized and the TiSe 2 -band levels decreases as x increases, contrary to what is usually observed for lower iron contents in related disordered materials. For x = 0.50, magnetostriction is evidenced below T N . Besides, the consequences of iron intercalation in TiSe 2 are analyzed from the viewpoint of the crystal dimensionality as deduced from a thermal expansion study.