Structures and syntheses of layered and framework amine-bearing uranyl phosphate and uranyl arsenates

摘要: Abstract Two hydrated uranyl arsenates and a phosphate were synthesized by hydrothermal methods in the presence of amine structure-directing agents their structures determined: (N2C6H14)[(UO2)(AsO4)]2(H2O)3, DabcoUAs, {NH(C2H5)3}[(UO2)2(AsO4)(AsO3OH)], TriethUAs, (N2C4H12)(UO2)[(UO2)(PO4)]4(H2O)2, PiperUP. Intensity data collected at room temperature using MoKα X-radiation CCD-based area detector. The crystal refined full-matrix least-squares techniques on basis F2 to agreement indices (DabcoUAs, PiperUP) wR2=5.6%, 8.3%, 7.2% for all data, R1=2.9%, 3.3%, 4.0%, calculated 1777, 5822, 9119 unique observed reflections (|Fo|⩾4σF), respectively. DabcoUAs is monoclinic, space group C2/m, Z=2, a=18.581(1), b=7.1897(4), c=7.1909(4) A, β=102.886(1)°, V=936.43(9) A3, Dcalc=3.50 g/cm3. TriethUAs P21/n, Z=4, a=9.6359(4), b=18.4678(7), c=10.0708(4) A, β=92.282(1)°, V=1790.7(1) A3, Dcalc=3.41 g/cm3. PiperUP Pn, a=9.3278(4), b=15.5529(7), c=9.6474(5) A, β=93.266(1)°, V=1397.3(1) A3, Dcalc=4.41 g/cm3. structure contains autunite-type sheet formed sharing vertices between square bipyramids arsenate tetrahedra. triethylenediammonium cations are located interlayer along with two H2O groups disordered. Both contain sheets pentagonal tetrahedra (arsenate phosphate, respectively) uranophane sheet-anion topology. In triethlyammonium interlayer. PiperUP, connected bipyramid that shares corners adjacent sheets, resulting framework piperazinium cavities structure.