Synthesis, property and crystal structure of a novel two-dimensional network organic–inorganic hybrid compound based on the neodymiumIII center and Keggin-type heteropolyanion of [a-BW12O40]52

A novel two-dimensional infinite network organic–inorganic hybrid neodymium(III)-centered compound of formula (dmaH)2[ Nd(dmf)4(H2O)][a-BW12O40]·H2O (1) [dma ¼ dimethylamine and dmf ¼ N,N-dimethylformamide] is obtained by the conventional selfassembly reaction of neodymium oxide, N,N-dimethylformamide and borotungstic acid (a-H5BW12O40·30H2O) in the mixed solvent of acetonitrile and water, and characterized by IR, UV–visible spectra and X-ray single crystal diffraction. Structural analysis indicates that every [a-BW12O40]52 polyanion interconnects with three adjacent [Nd(dmf)4(H2O)]3þ subunits by means ofW–O–Nd bridges, meanwhile, every [Nd(dmf)4(H2O)]3þ building block is surrounded by three neighboring [a-BW12O40]52 polyanions by making use of which an unprecedented two-dimensional extended network structure can be constructed. Interestingly, this structure pattern may act as useful model for the design and assembly of functional molecule-based compounds, especially in the field of molecular sieve materials. q 2004 Elsevier B.V. All rights reserved