Mixed-valence and neutral framework inorganic-organic hybrid materials: Synthesis, characterization, and magnetic properties of [{Co(N(CH)(4)N)}(V2O5)(2)] and [{Co(N(CH)(4)N)}V2O6]

作者：Khan M Ishaque^*; Yohannes Elizabeth; Golub Vladimir O; O'Connor Charles J; Doedens Robert J

来源：Chemistry of Materials, 2007, 19(20): 4890-4895.

DOI：10.1021/cm071415n

Two inorganic-organic hybrid materials [{Co(N(CH)(4)N)}(V2O5)(2)] (1) and [{Co(N(CH)(4)N)}V2O6] (2) have been synthesized and characterized by FT-IR spectroscopy, thermogravimetric analysis, elemental analysis, manganometric titration, temperature-dependent magnetic susceptibility measurement, bond valence sum calculations, and single-crystal X-ray diffraction analyses. The neutral framework materials were prepared by the amalgamation of vanadium oxide chains and layers with metal-organoamine coordination polymers. The three-dimensional framework structures of the crystals in 1 and 2 are composed of vanadium oxide layers (1) and chains (2) combined with {Co(N(CH)(4)N)}(2+) motifs that cross-link the reduced vanadium oxide layers (containing mixed-valent vanadium centers) in 1 and oxovanadium chains in 2. Besides crosslinking the metal oxide chains and layers in these materials, cationic metal-pyrazine polymers provide charge balance leading to the neutral framework in these solids. The compounds show good thermal stability. Crystal data for I is as follows: C4H4N2O10CoV4, orthorhombic space group Cmcm, a = 14.3071(6), b = 6.9965(3), c = 11.4510(5) angstrom, V = 1146.24(9) angstrom(3), Z = 4, D-calcd = 2.913 Mg.m(-3), R1 = 0.0385 (all data), wR2 = 0.1019. Crystal data for 2 are as follows: C4H4N2O6CoV2, orthorhombic space group Pnna, a 10.2524(8), b = 11.5653(9), c = 7.4719(6) angstrom, V = 885.96(12) angstrom(3), Z = 4, D-calcd = 2.526 Mg.m(-3), R1=0.0199 (all data), wR2 = 0.0547.

• 出版日期2007-10-2