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991.
A binicotinic biscarbohydrazone compound,2,2'-bipyridyl-3,3'-bis(N,N'-disali- cylidene)-formyhydrazone,1 has been prepared and characterized by elemental analysis,FT-IR,1H- NMR,ESI-MS and single-crystal X-ray diffraction analysis. The crystal belongs to triclinic,space group P1 with a = 9.419(3),b = 11.745(4),c = 12.035(5)A,V = 1178.8(7)A^3,Z = 2,Dc = 1.354 g/cm^3,μ = 0.095 mm^-1,F(000) = 500,λ(MoKα) = 0.71073 ,C26H20N6O4,Mr = 480.48,the final R = 0.0480 and wR = 0.1084 for 3634 observed reflections with I 〉 2σ(I). Single-crystal X-ray diffraction analysis reveals that a 1D supramolecular structure of 1 has been constructed by multiply intermolecular N–H···N and O–H···O H-bonding interactions. Besides,compound 1 exhibits a strong green-light emission in the solid state at room temperature. 相似文献
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Yoko Tatewaki Dr. Tatsuya Hatanaka Ryo Tsunashima Dr. Takayoshi Nakamura Prof. Mutsumi Kimura Prof. Hirofusa Shirai Prof. 《化学:亚洲杂志》2009,4(9):1474-1479
Tetrathiafulvalenes (TTF) S‐TTF and R‐TTF having four chiral amide end groups self‐organize into helical nanofibers in the presence of 2,3,5,6‐tetrafluoro‐7,7′,8,8′‐tetracyano‐p‐quinodimethane (F4TCNQ). The intermolecular hydrogen bonding among chiral amide end groups and the formation of charge‐transfer complexes results in a long one‐dimensional supramolecular stacking, and the chirality of the end groups affects the molecular orientation of TTF cores within the stacks. Electronic conductivity of a single helical nanoscopic fiber made of S‐TTF and F4TCNQ is determined to be (7.0±3.0)×10?4 S cm?1 by point‐contact current‐imaging (PCI) AFM measurement. Nonwoven fabric composed of helical nanofibers shows a semiconducting temperature dependence with an activation energy of 0.18 eV. 相似文献
996.
A three-dimensional complex [Cu(3-ampy)(H2O)4](SO4)·(H2O) (3-ampy = 3-aminopyridine) has been synthesized. Crystallographic data: C5H16CuN2O9S, Mr = 343.80, triclinic, space group P, a = 7.675(2), b = 8.225(3), c = 10.845(3) (A), α= 86.996(4), β = 76.292(4),γ = 68.890(4)°, V = 620.0(3) (A)3, Z = 2, Dc = 1.841 g/cm3, F(000) = 354 and μ = 1.971 mm-1. The structure was refined to R = 0.0269 and wR = 0.0659 for 1838 observed reflections (I > 2σ(Ⅰ)). The structure consists of [Cu(3-ampy)(H2O)4]2 cations, SO42- anions and lattice water molecules. 3-Ampy acting as a bidentate bridging ligand generates a 1D covalent chain. A supramolecular 2D framework is formed through π-π stacking of pyridine rings. The lattice water molecules and SO42- anions are located between the adjacent 2D frameworks. The hydrogen bonding interactions from lattice water molecules and SO42- anions to coordinate water extend the 2D framework into a 3D network. 相似文献
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Grzegorz Bejcar Piotr Przybylski Monika Walkowiak Bogumil Brzezinski 《Journal of Molecular Structure》2007,830(1-3):72-77
A new hydrazone of gossypol with 3,6,9-trioxadecylhydrazine (GHTO) has been synthesised and its structure has been studied by 1H NMR, 13C NMR, FT-IR spectroscopy and PM5 semiempirical methods. The results have shown that the newly synthesised hydrazone exists in solution in the N-imine–N-imine tautomeric form, stabilized by several intramolecular hydrogen bonds among which the O7H N16 intramolecular hydrogen bond is the strongest. The structure of GHTO is visualized by the PM5 semiempirical calculations. 相似文献
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本文基于鞅方法的定价理论,在全面考虑赎回条款、回售条款、公司不具稳定性的信用风险以及转股时股市受到稀释作用对可转债价值的影响后,给出可转换债券一个比较精确的定价公式。应用这些公式对南京水运公司可转换债券做实证分析,结果表明:定价公式的数值与实际市场可转债的价格波动情况吻合相当好,能反映出良好的预测效果.因此该可转债定价结果将有助于发行公司、投资者、监管机构和中介机构更准确的了解可转债的定价机制,而发行公司、投资者、监管机构和中介机构对可转债定价机制的熟悉将有助于在我国证券市场建立起一种成熟稳健的避险工具,从而推动证券市场的发展。 相似文献
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