Mössbauer study of non-stoichiometric FeCr2S4 system

© 2019 Elsevier B.V. A partial spin transition stimulated by spontaneous symmetry breaking has been observed, for the first time, in the non-stoichiometric chalcogenide spinel FeCr2S4. A Fe2+ high spin - low spin transition HS-LS: S = 2 → S = 0 is detected below the Néel temperature TN in the magnetic subsystem corresponding to a part of the sample with deviations from stoichiometry. The fraction of diamagnetic Fe atoms increases with decreasing temperature