Uranium(IV) oxide clusters, colloids, and materials are designed and studied for 1) nuclear materials applications, 2) understanding the environmental fate and transport of actinides, and 3) exploring the complex bonding behavior of open-shell f-elements. UIV -oxyhydroxsulfate clusters are particularly relevant in industrial processes and in nature. Recent studies have shown that counter-cations to these polynuclear anions differentiate rich structural topologies in the solid-state. Herein, we present nine different structures with wheel-shaped [U70 (OH)36 (O)64 (SO4 )60 ]4- (U70 ) linked into one- and two-dimensional frameworks with sulfate, divalent transition metals (CrII , FeII , CoII , NiII ) and UV . Small-angle X-ray scattering of these phases dissolved in butylamine reveals differing supramolecular assembly of U70 clusters, controlled primarily by sulfates. However, observed trends in transition metal linking guide future design of U70 materials with different topologies. Finally, U70 linking via UIV -O-UV -O-UIV bridges presents a rare example of mixed-oxidation-state uranium oxides without disorder.
Keywords: SAXS; actinides; polyanions; polyoxometalates; supramolecular; uranium.
© 2020 Wiley-VCH GmbH.