H2[(UO2)3(C7H3NO4)4] . 2H2O, M(r) = 1508.55, monoclinic, P2(1)/n, a =
8.881(6), b = 9.349(6), c = 21.458(6) angstrom, beta = 98.18(4)-degree
s, V = 1763.5 angstrom3, Z = 2, D(x) = 2.842 Mgm-3, lambda(MoK(alpha))
= 0.71069 angstrom, mu = 13.1 mm-1, F(000) = 1444, room temperature,
R = 0.066 for 2541 observations with I > 3sigma(I). In the trimer, two
of the uranyl groups have a pentagonal bipyramid coordination polyhed
ron with one dipicolinate acting as a terdentate ligand, and two monod
entate dipicolinate donors while the third uranyl has a hexagonal bipy
ramid coordination polyhedron with two terdentate dipicolinate ligands
saturating the equatorial plane. The three units are linked together
via bridging with carboxylate groups. Bond lengths and bond angles con
form well with other data for typical hexa and penta coordinated urany
ls.