Mixed-Valence and Neutral Framework Inorganic-Organic Hybrid Materials: Synthesis, Characterization, and Magnetic Properties of [{Co(N(CH)4N)}(V2O5)2] and [

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• 作者：M. Ishaque Khan ; Elizabeth Yohannes ; Vladimir O. Golub ; Charles J. O'Connor ; Robert J. Doedens
• 刊名：Chemistry of Materials
• 出版年：2007
• 出版时间：October 2, 2007
• 年：2007
• 卷：19
• 期：20
• 页码：4890 - 4895
• 全文大小：271K
• 年卷期：v.19,no.20(October 2, 2007)
• ISSN：1520-5002

文摘

Two inorganic-organic hybrid materials [{Co(N(CH)₄N)}(V₂O₅)₂] (1) and [{Co(N(CH)₄N)}V₂O₆] (2)have been synthesized and characterized by FT-IR spectroscopy, thermogravimetric analysis, elementalanalysis, manganometric titration, temperature-dependent magnetic susceptibility measurement, bondvalence sum calculations, and single-crystal X-ray diffraction analyses. The neutral framework materialswere prepared by the amalgamation of vanadium oxide chains and layers with metal-organoaminecoordination polymers. The three-dimensional framework structures of the crystals in 1 and 2 are composedof vanadium oxide layers (1) and chains (2) combined with {Co(N(CH)₄N)}²⁺ motifs that cross-link thereduced vanadium oxide layers (containing mixed-valent vanadium centers) in 1 and oxovanadium chainsin 2. Besides crosslinking the metal oxide chains and layers in these materials, cationic metal-pyrazinepolymers provide charge balance leading to the neutral framework in these solids. The compounds showgood thermal stability. Crystal data for 1 is as follows: C₄H₄N₂O₁₀CoV₄, orthorhombic space groupCmcm, a = 14.3071(6), b = 6.9965(3), c = 11.4510(5) Å, V = 1146.24(9) ų, Z = 4, D_calcd = 2.913Mg·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) Å, V = 885.96(12) ų,Z = 4, D_calcd = 2.526 Mg·m^-3, R1 = 0.0199 (all data), wR2 = 0.0547.