Hydrothermal synthesis, crystal structure, and spectroscopic characterization of a new organically templated mixed-anion fluoro-arsenate-phosphate iron(III) compound, (C2H10N2)[Fe2(AsO4)2−x(PO4)xF2(H2O)] (x = 0.46)

A new organically templated mixed-anion fluoro-arsenate-phosphate iron(III) compound, (C2H10N2)[Fe2(AsO4)2−x(PO4)xF2(H2O)] (x=0.46), has been synthesized by using mild hydrothermal conditions under autogeneous pressure. The crystal structure has been solved from X-ray single-crystal data. The compound crystallizes in the Pbca orthorhombic space group, with the unit-cell parameters a=10.457(4), b=10.093(3), c=20.479(1) Å and Z=8. The crystal structure consists of a three-dimensional inorganic framework containing two different kinds of layers. The sheets are formed by Fe2O8F2 edge-sharing dimer octahedra and FeO5F octahedra, which are connected to the AsO4 and PO4 tetrahedra. The IR spectrum shows the bands of the ethylenediammonium cation and the arsenate and phosphate anions.