HYDROTHERMAL SYNTHESIS, STRUCTURE AND MAGNETIC-PROPERTIES OF [FE-3(PO4)(3)F-2,H3N-(CH2)(4)-NH3] - THE ANALOG OF THE 3-DIMENSIONAL GALLOPHOSPHATE STRUCTURE-TYPE ULM-3

[Fe-3(PC)(4))(3)F-2, H3N-(CH2)(4)-NH3] has been synthesized hydrotherm ally (453 K, 24 h, autogenous pressure). Its structure was determined by single-crystal X-ray diffraction. It is orthorhombic (space group P bca No. 61) with cell parameters a = 10.203(1) Angstrom, b = 18.670(1) Angstrom, c = 16.268(1) Angstrom, V = 3099(1) Angstrom(3) and Z = 8. Its three-dimensional structure, refined to R(1)(F-0) = 0.036 and wR(2 )(F-0(2)) = 0.093 from 6821 unique reflections (I > 2 sigma(I)) is iso structural with the oxyfluorinated gallophosphate ULM-3. From a struct ural point of view, this leads to 10-membered channels along [100]. It is also an antiferromagnetic compound which orders at T-N = 37(2) K. Mossbauer data are consistent with the presence of two distinct Fe3+ s ites in the high spin state: one corresponding to Fe3+ in an octahedra l site and the other to two Fe3+ in trigonal bipyramids, Magnetic coup lings are discussed in terms of superexchange and supersuperexchange i nteractions.