The First Organically Templated Tetravalent Uranium Phosphates with Dimer-Structured Topologies

Abstract

Four new organically templated uranium(IV) phosphates, (C4H16N3)[U2F3(PO4)2(HPO4)] (1), (C6H21N4)[U2F4(PO4)(HPO4)2] (2), (C4H16N3)2[U2F10(HPO4)2] (3), and (C6H16N2)2(UF7)(H2PO4) (4), have been successfully synthesized in pure-phase form under mild solvothermal conditions and characterized by single-crystal X-ray diffraction, magnetic susceptibility, thermogravimetric analysis (TGA), elemental analysis, inductively coupled plasma−atomic emission spectroscopy, and fluorine analysis. They are the first tetravalent uranium phosphates with encapsulated organic templates ever reported. All four materials display unique dimer-structured topologies with various dimensionalities in the inorganic/hydrogen-bonded networks. In this series, U4+ ions are located in the center of bicapped trigonal prisms of UFO7, UF2O6, UF6O2, or UF8, from which edge-sharing U2FmO14−m dimers (m = 2 and 4 in 1, m = 4 in 2, m = 10 in 3, and m =14 in 4) are formed. The less-fluorinated U2F2O12 and U2F4O10 dimers are connected to eight and ...