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 degrees 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.