Peroxide-promoted disassembly-reassembly of Zr-polyoxocations

Zr/Hf aqueous-acid clusters are relevant to inorganic nanolithography, metal-organic frameworks (MOFs), catalysis and nuclear fuel reprocessing, but only two topologies have been identified. The (Zr4) polyoxocation is the ubiquitous square aqueous Zr/Hf-oxysalt of all halides (except fluoride), and prior-debated for perchlorate. Simply adding peroxide to Zr oxyperchlorate solution leads to a striking modification of Zr4, yielding two structures identified by single-crystal X-ray diffraction. Zr25, isolated from a reaction solution of 1:1 peroxide:Zr, is fully formulated [Zr25O10(OH)50(O2)5(H2O)40](ClO4)10xH2O. Zr25 is a pentagonal assembly of 25 Zr-oxy/peroxo/hydroxyl polyhedra and is the largest Zr/Hf cluster topology identified to date. Yet is yet completely soluble in common organic solvents. ZrTd, an oxo-centered tetrahedron fully formulated [Zr4(OH)4(μ-O2)2(μ4-O)(H2O)12](ClO4)6xH2O, is isolated from a 10:1 peroxide:Zr reaction solution. The formation pathways of ZrTd and Zr25 in water were describe...