pH-controlled assembly of two polyoxovanadates based on [V16O38(Cl)]8− and [V15O36(Cl)]6− building blocks

Two new inorganic–organic hybrid polyoxovanadates, [Cu(2,2′-bipy)3]2[H4V16O38(Cl)]·4H2O 1 and [Cu(2,2′-bipy)3]3[V15O36(Cl)]·3H2O 2 (2,2′-bipy=2,2′-bipyridine), have been prepared under the hydrothermal conditions and structurally characterized by elemental analysis, IR spectra, EPR spectra, TG analyses and single-crystal X-ray diffraction. Compounds 1 and 2 are based on [V16O38(Cl)]8− and [V15O36(Cl)]6− building block, respectively. They were synthesized under the same reaction condition but in different pH range, which shows that the pH value of the reaction plays a key role in the structural control of self-assemble process.