Two Types of Polyoxometalates Based on Circular P8W48 Cluster Units and Different Inclusions of Tetralanthanide and Octamanganese Centers


  • Dedicated to Professor Michael T. Pope on the occasion of his 80th birthday


Two types of new polyoxometalates (POMs) based on circular P8W48 clusters with different tetralanthanide (Ln) clusters and octamanganese centers, [K(H2O)2]4[K4(μ-H2O)4(H2O)4]2{[Ln2(μ-OH)4(H2O)x]2(H24P8W48O184)}·yH2O [Ln = Nd (1), Sm (2), Tb (3)] and [K(H2O)2]4[K4(μ-H2O)8]2[K(H2O)]8{[Mn8(H2O)16](H4P8W48O184)}·36H2O (4) have been synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction, elemental analysis, IR spectroscopy, thermogravimetry (TG), and powder XRD. Compounds 13 are the first series of Ln-containing P8W48-based POMs that use P2W12O4814– as the precursor; previously known P8W48-based POMs used P8W48O18440– as the precursor. In 4, eight manganese ions were incorporated. Owing to the different radii of the Ln and Mn ions, the four large Ln ions are divided into two {Ln2} clusters located on two sides of the cavity of the P8W48 wheel in 13, but the eight small manganese ions in 4 only bond to the inside of the P8W48 wheel and do not form manganese clusters. The magnetic properties of 3 are discussed.