Network Dimensionality of Selected Uranyl(VI) Coordination Polymers and Octopus-like Uranium(IV) Clusters

Using slow diffusion methods at room temperature, five uranium coordination polymers were obtained, which either employ glutarate (Glut), terephthalate (TP), or 2-aminoterephthalate (TPNH2) as bridging systems. Four of these networks are based on the uranyl(VI)-unit, UO22+, and one formed through the integration of tetravalent uranium as the coordinating metal center. [[UO2](TP)(H2O)2]·2THF (1) arranges as intermeshed one-dimensional (1D) infinite linear chains, locked into a three-dimensional (3D) network through hydrogen bonds with a uninodal 4-coordinated uom topology. [[UO2](TPNH2)(H2O)2]·2H2O (2) assembles as intermeshed two-dimensional (2D) layers, also stabilized as a 3D network through hydrogen bonding with a 2-nodal 4-coordinated pts network topology. Na2[[UO2]2(TP)3]·9H2O (3) forms parallel layers that are stacked in an AB pattern. Layers possess the uninodal 3-coordinate honeycomb (hcb) motif. Na2[[UO2]2(Glut)3]·8H2O (4) assembles as a 3D-coordination network with a uninodal 3-c srs (SrSi2) topology. The fifth compound contains uranium(IV) and the glutarate entity; U6(NO3)4(Glut)4(O)4(OH)4(H2O)6·12H2O (5). The long-range structure of 5 adopts a 3D open framework, as it includes the flexible glutarate linker, in which U6O8 secondary building units assemble as U6O38 superclusters. These clusters are interlinked by the glutarate spacers resulting in a body centered cubic (bcu) topology.