Synthesis, crystal structure and characterization of a praseodymiumIII-substituted silicotungstate with a novel 1D chain connection motif

The reaction of the mono-lacunary silicotungstate ligand α-K8SiW11O39 · 13H2O with praseodymiumIII cation results in a new Keggin-type derivative K3[(Pr(H2O)4SiW11O39)(NaPr2(H2O)12)(Pr(H2O)4SiW11O39)] · 13.5H2O (1), whose polyanion consists of two crystallographically distinct [Pr(H2O)4SiW11O39]5− building block units and one [NaPr2(H2O)12]7+ subunit, which are connected by alternating praseodymium and sodium centers via the terminal and bridging oxygen atoms from the precursor [α-SiW11O39]8− to construct a 1D infinitely chainlike structure.