Experimental and computational study of a new wheel-shaped {[W5O21]3[(U(VI)O))2(μ-O2)]3}30- polyoxometalate

A new wheel-shaped polyoxometalate {[W(5)O(21)](3)[(U(VI)O(2))(2)(μ-O(2))](3)}(30-) has been synthesized and structurally characterized. The calculated electrostatic potential reveals the protonation of several μ-oxo bridges reducing the polyoxometalate total charge. A protonated structure computed at the density functional level of theory (DFT) is in good agreement with the experimental fit. This species presents a classical polyoxometalate electronic structure with well-defined metal and oxo bands belonging to its U/W and oxo/peroxo constituents, respectively. Furthermore, fragment calculations indicate that the electronic structures of the uranyl-peroxide and polyoxotugstate fragments are little affected by the nanowheel assembly.