The effects of titanium ions on the crystallographic and spin-rotation transitions in iron sulfide have been
examined by Mössbauer spectroscopy in the temperature range of 78 to 600 K. It is noted that the titanium
impurity of Ti_0.02Fe_0.98S  affects both the crystallographic and spin-rotation transitions of the iron sulfide. 2% impurity of Ti2+ in FeS causes the increase in the difference between the spin rotation and α transition temperature by as much as 10 K compared with that for FeS. Both 1c and 2c structures coexist in the range between the α transition temperature and approximately 26 K, with a smaller hyperfine field corresponding to the 1c structure. The spin-rotation temperature for Ti_0.02Fe_0.98S was measured to be 365 K, which is 10 K lower than the α transition temperature. By the 2% impurity of Ti²⁺ in FeS the Néel temperature appreciably is not affected.