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Synthesis and Structural Characterization of a Polyoxomolybdate HNa_7[Mo_(36)O_(112)(H_2O)_(16)]·47H_2O

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Chinese Journal of Structural Chemistry 2007年第2期26卷 165-171页

作者： LIU Ying DOU Jian-Min WANG Da-Qi ZHANG Xian-Xi LI Da-Cheng JIA Ying-Chun College of Chemistry and Chemical Engineering Liaocheng University Liaocheng 252059 China

A new polyoxomolybdate complex HNaT[Mo36O112（H2O）16]·47H2O 1 has been prepared in the beaker solution and characterized by single-crystal X-ray diffraction and elemental analyses. Crystal data： H127Mo36Na7O175, Mr = 6542.79, monoclinic, C2/c, a = 40.891（6）, b = 17.900（3）, c = 25.580（4）A, β = 125.673（2）°, V = 15210（4）A3, Z = 4, Dc = 2.857 g/cm^3, F（000） = 12464,μ = 3.013 mm^-1, R = 0.0633 and wR = 0.1654 （I 〉 20（I））. With the bridging sodium cations, the [Mo36Ou2（H2O）16]^8- units in compound 1 are linked to form a one-dimensional structure, on the basis of which a three-dimensional architecture is further constructed via other sodium cations and complicated hydrogen bonds.

关键词： polyoxomolybdate molybdate sodium X-ray analysis

Synthesis and Crystal Structure of Diethyl 5-Acetoxy-3-(4-chlorophenyl)- 4,5-dihydroisoxazol-5-yl-5-phosphonate

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Chinese Journal of Structural Chemistry 2006年第12期25卷 1453-1456页

作者：尚志强陈茹玉黄有 State Key Laboratory of Elemento-organic Chemistry Institute of Elemento-organic Chemistry Nankai University

The crystal structure of the title compound, diethyl 5-acetoxy-3-（4-chlorophenyl）-4,5- dihydroisoxazol-5-yl-5-phosphonate （C15H19CINO6P, Mr = 375.73）, has been synthesized by the treatment of nitrile oxides and l-acetyloxy-vinylphosphonate under very mild conditions in good yields, and determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group C2/c with a = 16.914（10）, b = 10.567（7）, c = 21.927（13） A, β = 110.249（11）°, V = 3677（4） A^3, Z = 8, Dc = 1.358 g/cm^3, F（000） = 1568,/l（MoKa） = 0.324 mm^-1）, S = 1.011, the final R = 0.0661 and wR = 0.1556. The X-ray analytic results showed that the dihedral angle between the phenyl group and the isoxazoline ring is 10.7°.

关键词： crystal structure isoxazolines phosphonate synthesis

Synthesis, Crystal Structure and Magnetic Property of the Polymeric Ribbon: [Co(ip)(phen)]_n

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Chinese Journal of Structural Chemistry 2005年第5期24卷 503-508,489页

作者：周有福时茜袁大强许颜清洪茂椿 State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China

A metal-organic coordination polymer [Co(ip)(phen)]n (ip = isophthalate, phen = 1,10-phenanthroline) 1 has been hydrothermally synthesized and characterized. Compound 1 crystallizes in P2/c space group with a = 8.37(2), b = 10.41(1), c = 18.36(3) ?, β = 100.41(7)o, C20H12CoN2O4, Mr = 403.25, V = 1573(4) ?3, Z = 4 and Dc = 1.703 g/cm3. Two Co(II) ions are bridged by μ-carboxylate to form a dinuclear unit, which is extended by ip ligands resulting in a ribbon-like chain. Pairs of phen ligands attach to the dinuclear units on both sides of the chain alternately. Magnetic study reveals that the interaction between the carboxylate-bridged Co(II) ions in 1 is weakly antiferromagnetic.

关键词： cobalt isophthalate 1,10-phenanthroline crystal structure magnetism

Synthesis and Crystal Structure of an Inclusion Compound Mn(SCN)_2(H_2O)_4·2C_6H_(12)N_4

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Chinese Journal of Structural Chemistry 2005年第7期24卷 821-823,739页

作者： WANGWen-Guo CHENChang-Neng LIUQiu-Tian StateKeyLaboratoryofStructuralChemistry FujianInstituteofResearchontheStructureofMatterTheChineseAcademyofSciencesFuzhouFujian350002China

A mononuclear manganese complex Mn(SCN)2(H2O)4?2C6H12N4 (C14H32O4N10MnS2, C6H12N4 = hexamethylenetetramine) has been synthesized. The molecular and crystal structures were determined by single-crystal X-ray diffraction. The crystal is of tetragonal, space group P42/mnm with a = 9.5591(7), b = 9.5591(7), c = 13.8253(15) ?, V = 1263.31(19) ?3, Z = 2, Mr = 523.56, Dc = 1.376 g/cm3, μ = 0.727 mm-1, F(000) = 550, Rint = 0.0302, T = 293(2) K, R = 0.0380 and wR = 0.1184 for 549 observed reflections with I > 2σ(I). In the crystal the manganese atom is six-coordinated by two nitrogen atoms from isothiocyanato anion and four oxygen atoms from water molecules, completing an octahedral geometry. Hexamethylenetetramine molecules are included in the lattice and connected to Mn(SCN)2(H2O)4 by hydrogen bonding and S…S interac- tions to form a three-dimensional supramolecular architecture.

关键词： manganese complex crystal structure hexamethylenetetramine

Interaction of Hypocrellin B or Mono-cysteine Substituted Hypocrellin B with CT-DNA by Spectral Methods

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Chinese Chemical Letters 2003年第10期14卷 1054-1057页

作者： Jia Hong ZHOU, Sheng Qin XIA,Xue Song WANG, Bao Wen ZHANG, Yi CAO Technical Institute of Physics and Chemistry, Chinese Academy of Sciences,Beijing 100101 Tech. Inst. of Physics and Chemistry Chinese Academy of Sciences Beijing 100101 China

The interaction of the anticancer drug hypocrellin B (HB) or the mono-cysteine substituted hypocrellin B (MCHB) and calf thymus deoxyribonucleic acid (CT-DNA) has been investigated using spectral methods. The results of UV-visible spectra show that the HB and MCHB could intercalate into the base-stacking domain of the CT-DNA double helix. The studies of fluorescence spectra and circular dichroism(CD) spectra also support the interacalation mechanism.

关键词： Hypocrellin B mono-cysteine substituted hypocrellin B CT-DNA interacalation mechanism.

Harmonic Maps from Kahler Manifolds

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Acta Mathematica Sinica,English Series 1999年第2期15卷 277-292页

作者： Yuanlong Xin, Institute of Mathematics and LMNS, Fudan University, Shanghai 200433, P. R. ChinaE-mail: ylxin@fudan, edu. cn Institute of Mathematics and LMNS Fudan University Shanghai P. R. China

Some Liouville type theorems for harmonic maps from Kahler manifolds are obtained. The main result is to prove that a harmonic map from a bounded symmetric domain (except IV（2）) to any Riemannian manifold with finit... 详细信息

关键词： Harmonic map Kahler manifold Bounded symmetric domain

Homoclinic Bifurcation of Orbit Flip with Resonant Principal Eigenvalues

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Acta Mathematica Sinica,English Series 2006年第3期22卷 855-864页

作者： Tian Si ZHANG De Ming ZHU Department of Mathematics East China Normal University

Codimension-3 bifurcations of an orbit-flip homoclinic orbit with resonant principal eigenvalues are studied for a four-dimensional system. The existence, number, co-existence and noncoexistence of 1-homoclinic orbit, 1-periodic orbit, 2n-homoclinic orbit and 2n-periodic orbit are obtained. The bifurcation surfaces and existence regions are also given.

关键词： Orbit flip Homoclinic orbit Periodic orbit Resonance Principal eigenvalues

Synthesis and Crystal Structure of a Luminescent Compound 5-(1H-benzoimidazol-2-yl)-3H-[1,2,3]triazole-4-carboxylic Acid

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Chinese Journal of Structural Chemistry 2012年第11期31卷 1662-1668页

作者：孙晨光曾明华徐抗震宋纪蓉 School of Chemical Engineering Northwest University College of Chemistry & Materials Science Northwest University

The title compound, 5-（1H-benzoimidazol-2-yl）-3H-[1,2,3]triazole-4-carboxylic acid （CIoH.7Ns.O2.C3H7NO, M,..= 302.30）, has been synthesized and characterized by FT-IR and ES1-MS, ~H-NMR spectroscopy and X-ray single-crystal diffraction. Crystal structure of the title compound was grown from DMF by slow diffusion at room temperature. Crystal data： orthorhombic structure, space group Pna2＋ with a = 6.9635（3）, b = 19.4398（7）, c = 30.6165（12） A, V = 4144.5（3） A3, Z = 12, Dc = 1.454 g/cm3,/l（MoKa） = 0.108 mm-1, and F（000） = 1896. The structure was refined to R = 0.0450 and wR = 0.0975 for 3578 observed reflections with 1 〉 2σ（I）. The interm01ecular hydrogen bonds and π-π stacking further stabilize the structure.

关键词： benzimidazole derivatives crystal structure ESI-MS fluorescence ESIPT

Crystal Structure and Photochromism in Paint of 1,3,3-Trimethyl-6'-dihydro-indolinyl- spiro[2,3'-[3H]-naphtho[2,1-b][1,4]]oxazine

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Chinese Journal of Structural Chemistry 2007年第5期26卷 572-574页

作者： TAN Ting-Feng Department of Materials Science ＆ Engineering Tianjin Institute of Urban Construction Tianjin 300384 China

The title compound 2 （C30H27N3O, Mr = 445.55） has been synthesized and its structure was determined by X-ray crystallography method. The crystal is of monoclinic, space group P21/c with a = 17.520（15）, b = 8.640（7）, c = 15.439（13） A, β = 98.642（14）°, V = 2310（3） 3, Dc = 1.281 g/cm^3, μ = 0.780 mm^-1, F（000） = 944, Z = 4, the final R = 0.0671 and wR = 0.1790 for 1952 observed reflections with Ⅰ 〉 2σ（Ⅰ）. X-ray analysis revealed that the interatomic distance of C（20）O（1） is 1.464（4） , longer than that of the normal C-O bond （1.41～1.43 A） in the six-membered heterocycle, but this kind of change coincides with other spiro compounds. The six-membered heterocycle containing spiro Csp3-O is nonplanar. The UV-vis spectra of the title compound in polymer films showed that it exhibits excellent photochromic property.

关键词： spirooxazine crystal structure photochromism