  The measurements of the magnetic susceptibility, magnetization, electrical
resistivity and magnetoresistance have been performed for the Fe intercalated
compound Fe0.5TiS2. According to X-ray diffraction measurements the Fe0.5TiS2
compound synthesized in the present work has a monoclinic crystal structure
(space group I12/m1) which results from the ordering of Fe ions and vacancies
between S-Ti-S tri-layres. The changes in the heat-treatment conditions at
temperatures below 1100 Celsius degrees do not lead to an order-disorder
transition within the subsystem of intercalated Fe ions. It has been shown that
this compound exhibits an antiferromagnetic (AF) ground state below the Neel
temperature TN = 140 K. Application of the magnetic field at T < TN induces a
metamagnetic phase transition to the ferromagnetic (F) state, which is
accompanied by the large magnetoresistance effect (up to 27 %). The
field-induced AF-F transition is found to be irreversible below ~ 100 K. The
magnetization reversal in the metastable F state at low temperatures is
accompanied by substantial hysteresis (~ 100 kOe) which is associated with the
Ising character of Fe ions.
