Synthesis and characterization of a new transition-metal complex of the Lindqvist polyanion Na[Cu(1, 3-pda)(2)](3)[HNb6O19]center dot 3H(2)O

A new transition-metal (TM) complex of the Lindqvist polyanion Na[Cu(1, 3-pda)2]3[HNb6O19] 3H2O (1, 3-pda = 1, 3-diaminopropane) has been prepared using pre-prepared TBA4[H4Nb6O19] 7H2O as a precursor and characterized by single crystal X-ray diffraction, elemental analyses, IR spectra, and thermogravimetric analysis. Crystal data for the compound: rhombohedral, space group R-3c, a = 14.927(4) , b = 14.927(4) , c = 36.940(18) , = 120, V = 7128(4) 3, Z = 6. The structural unit of the title compound consists of a polyanion [HNb6O19]7-, a Na+, three [Cu(1, 3-pda)2]2+, and three crystal water molecules. The occupancy of all Cu atoms and water molecules is 0.5. X-ray diffraction indicated that the cations and the polyanion were linked through electrostatic interactions and intermolecular forces.