Further Mössbauer Studies of Vivianite, Fe₃(PO₄)₂8H₂O

Abstract

The temperature dependence of internal magnetic fields in Fe₃(PO₄)₂8H₂O was obserbed by the Mössbauer effect. It was made clear that although the temperature dependences of the two sublattices are greatly different, both internal fields disappear at the same temperature, 9.0 K. Measurements were also made at 4.2 K in the presence of an external field up to 50 kOe, whose direction was perpendicular to the crystal ac plane where the two spin easy directions are included. The ferromagnetic spin flipping occurred only at the sublattice of Fe I.