STRUCTURAL STUDIES ON ACTINIDES CARBOXYLATES .5. CRYSTAL AND MOLECULAR-STRUCTURE OF AMMONIUM URANYLDIMALONATE MONOHYDRATE (NH4)2[UO2(C3H2O4)2].H2O

The crystal structure of the title compound has been determined from single crystal diffractometer data. The crystals are monoclinic, space group P21/c, a = 12.112(3), b = 7.217(2), c = 16.359(4), β = 111.96(10), Z = 4.1845 reflections were refined to a final R = 4.7%. The crystals contain water, NH4+ and [UO2(C3H2O4)2]n2n-1 ions. In the latter, one malonate group is bidentate and the second terdentate, giving chains parallel to b. Both ligands form six-membered rings with uranium. The uranyl UO distance (mean value) is 1.76 Å and the geometry around the uranium is approximately pentagonal bipyramidal. © 1979.