Crystal Growth and Structure of the New Ferrimagnetic Oxyphosphate PbFe3O(PO4)3



A new oxyphosphate, PbFe3O(PO4)3, has been discovered and its structure has been characterized by single-crystal XRD between 293 and 973 K (monoclinic, space groupP21/m, a = 7.5826 Å, b = 6.3759 Å, c = 10.4245 Å, β = 99.956°, Z = 2, at r.t.). Direct-current (DC) magnetic susceptibility and specific heat measurements performed on single crystals revealed an unusual sequence of second-order ferromagnetic-like phase transitions at Tc1 = 31.8 K, Tc2 = 23.4 K and Tc3 ≈ 10 K. Alternating-current (AC) magnetic susceptibility measurements suggest glass-like dynamics between ca. 20 K and Tc3.