One-Dimensional Uranyl-2,2′-bipyridine Coordination Polymer with Cation–Cation Interactions: (UO2)2(2,2′-bpy)(CH3CO2)(O)(OH)

A uranyl-2,2′-bipyridine coordination polymer, (UO2)2(2,2′-bpy)(CH3CO2)(O)(OH) (1; 2,2′-bpy = 2,2′-bipyridine) has been synthesized hydrothermally at 165 °C and characterized via single-crystal X-ray diffraction and UV–vis–near-IR, fluorescence, and IR spectroscopies. The structure consists of two uranyl pentagonal bipyramids that are linked through cation–cation interactions (CCIs) to form chains that are truncated in the second and third dimensions by 2,2′-bpy. These chains of uranyl polyhedra consist of a rare case of CCIs through the edge-sharing polyhedral connection mode instead of the more common corner-sharing connection mode. 1 is the first uranium(VI) compound reported that contains CCIs in which the structural unit is one-dimensional, although lower-dimensional structural units with CCIs are known for pentavalent actinides.