Tetra-μ(2)-acetato-tetraaquadi-μ(3)-oxido-octaoxidotetrauranium(VI) methanol disolvate tetrahydrate.

The centrosymmetric title tetra-mer, [U(4)(C(2)H(3)O(2))(4)O(10)(H(2)O)(4)]·2CH(4)O, has a near planar core [maximum deviation from the least squares plane of 0.294†(6)†à ]. It consists of two hexa-gonal-bipyramidally coordinated U(VI) atoms connected via μ(2)-O (acetate) and μ(3)-O (oxide) bridges in the equatorial plane to two penta-gonal-bipyramidally coordinated U(VI) atoms. The equatorial plane of each U(VI) atom is completed by a bound water mol-ecule, while the axial positions are occupied by uranyl (UO(2))(2+) O atoms. Multiple O-H⋯O hydrogen bonds are present, including a lattice methanol mol-ecule bound to one of the penta-gonal bipyramidal uranyl O atoms, as well as two different C(1) (1)(6) chains orginating from a donor water mol-ecule, via a uranyl oxygen acceptor and an acetate acceptor on different, adjacent tetra-mers. Finally, the unit cell contains four U(VI) tetra-mers, all connected by hydrogen bonding, forming a supra-molecular R(4) (4)(24) ring.