Synthesis and Crystal Structure of Fe3(H2PO4)4(PO4)2. (H3O+)2H2O, a Novel Iron Phosphate

Institute of Marine Bio Technology, National Taiwan Ocean University
â—‹Hsiu-Mei Lin Shi-Fang Yeh

A new iron phosphate, Fe3(H2PO4)4(PO4)2.(H3O+)2H2O, has been synthesized under hydrothermal conditions. The resulting product consists of light purple plate-shaped crystals of the title compound. Its structure has been determined by single crystal X-ray diffraction. Crystal data: triclinic, space group P-1, a = 7.1545 (2), b = 8.8195 (2), c = 9.4368 (2) Å, alpha = 64.849(1), beta = 70.215(1), gamma = 69.386(1)degree, V = 491.8(3) Å3, Z = 2, and R1(Rw) = 0.027(0.075). Crystal data were collected on a Simens CCD diffractometer with Mo Kalpha(lada=0.7103Å) at room temperature. There are two unique iron atoms in the crystal structure, having octahedral oxygen coordination, FeO6 octahedral are linked together via corners of PO4 tetrahedral to form a three-dimensional network. Within this network are hollows that are occupied by oxonium ions, lie on crystallographic twofold axis. The synthesis and crystal structure of the title compound will be presented.