Coordination of lanthanide cation to an Anderson type polyoxometalate anion leads to isomorphous metal-oxide based one-dimensional inorganic solids: Synthesis, crystal structure and spectroscopy

Abstract

One-dimensional isomorphous inorganic polymers containing Anderson type heteropoly anion as a basic building unit, namely [La(H2O)7Cr(OH)6Mo6O18]n·4nH2O (1), [Gd(H2O)7Cr(OH)6Mo6O18]n·4nH2O (2), [Gd(H2O)7Al(OH)6Mo6O18]n·4nH2O (3), and [Eu(H2O)7Al(OH)6Mo6O18]n·4nH2O (4) have been synthesized and studied by the powdered X-ray diffraction, TGA, IR, electronic and ESR spectroscopy, and unambiguously by single crystal X-ray crystallography. Isomorphous compounds 1-4 are crystallized in orthorhombic system with Pca2 1 space group. The crystal structure analysis reveals a one-dimensional extended chain in which the Anderson type heteropolyanion, acting as the building unit, is linked by rare earth metal ions in a zig-zag fashion. In the crystal structure, all types of oxygens of the heteropolyanion, lattice waters, lanthanum coordinated waters are extensively involved in O - H ⋯O hydrogen bonding interactions. Compounds are additionally characterized by UV-visible and ESR spectroscopy. [Figure not available: see fulltext.]