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Theoretical Study on the Di-, Tri- and Tetra-cage Coplanar Cubane

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Chinese Journal of Structural Chemistry 2004年第7期23卷 768-772页

作者：刘奉岭王海燕于淑媛李怀祥 Department of Chemistry Shandong Normal UniversityJinan 250014China

The di-, tri- and tetra-cage coplanar cubanes have been studied at B3LYP/D95** and MP2/D95** levels, and their vibrational frequencies have been calculated at B3LYP/D95** level. All of these species have no imaginary vibrational frequency, so that each of the molecules is a mini- mum at the potential energy hypersurface. Many properties of the molecules, such as geometries, heats of formation and the first ionization potentials, have been studied in this paper.

关键词：二笼立方烷三笼立方烷四笼立方烷量子化学振动频率几何构型

Synthesis and Crystal Structure of an Imino Nitroxide Complex [Cd(IM2py)_2Cl_2]

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Chinese Journal of Structural Chemistry 2004年第11期23卷 1218-1221页

作者：王淑萍刘翠格高东昭廖代正姜宗慧闫世平 Department of Chemistry Nankai University Tianjin 300071 China Department of Chemistry Hebei Normal University Shijiazhuang 050091 China Department of Chemistry Nankai University Tianjin 300071 ChinaState Key Laboratory of Coordination Chemistry Nanjing 210093 China

The title compound [Cd(IM2py)2Cl2], where IM2py = 2-(2?-pyridinyl)-4,4,5,5-tetra- methylimidazoline-1-oxyl, has been prepared and structurally characterized by X-ray diffraction. It crystallizes in monoclinic, space group C2/c with a = 18.436(6), b = 9.255(3), c = 15.831(5) ? b = 100.274(5)? C24H32CdCl2N6O2, Mr = 619.86, V = 2658.0(14) ?, Z = 4, Dc = 1.549 g/cm3, m(MoKa) = 1.056 mm-1, F(000) = 1264, the final R = 0.0324 and wR = 0.0659 for 2725 independent reflections with Rint = 0.0378. The title complex exists as discrete mononuclear molecules, adopting a distorted octahedral [cis(Cl)-trans(py)] configuration with the cadmium(II) ion being bonded to two bidentate radicals and two chlorine atoms. There exist p???p stacking interactions between the adjacent parallel pyridyl rings of the complex in the ac plane.

关键词： crystal structure imino nitroxide radical cadmium(II) complex

On the Multiplicity of a C~∞-differentiable Function-germ

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Acta Mathematica Sinica,English Series 2007年第4期23卷 711-714页

作者： Xu XU College of Mathematics & Statistics Wuhan University Wuhan 430072 P. R. China

Risler ＆ Trotman in 1997 proved that the multiplicity of an analytic function germ is left-right lipschitz invariant, which provided a partial answer to Zariski conjecture. In this note, based on the recent work of Comte, Milman ＆ Trotman, we generalize the work of them to prove that the multiplicity of a C^∞ differentiable function germ is also left-right lipschitz invariant.

关键词： smooth function germ multiplicity bilipschitz maps

PRICING AND HEDGING OPTION UNDER PORTFOLIO CONSTRAINED

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Acta Mathematica Scientia 2001年第4期21卷 483-494页

作者：魏刚陈世平 Department of Financial Mathematics Beijing University Beijing 100871 China

The authors employ convex analysis and stochastic control approach to study the question of hedging contingent claims with portfolio constrained to take values in a given closed, convex subset of RK, and extend the re... 详细信息

关键词： super-replication stochastic control portfolio constraints

Two New ent-Kaurenoids from Cacalia pilgeriana

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Chinese Chemical Letters 2005年第5期16卷 625-626页

作者： ErWeiLI KunGAO ZhongJianJIA XinZHAO CollegeofChemistryandChemicalEngineering NationalLaboratoryofAppliedOrganicChemistryLanzhouUniversityLanzhou730000

Two new ent-kaurenoids, 19-acetyl-ent-3β, 17-dihydroxykaur-15-ene (1), 19-acetyl-ent-3β-hydroxykaur-15-en-17-a1 (2) were isolated from Cacalia pilgeriana. Their structures were elucidated by spectroscopic methods.

关键词： Cacalia pilgeriana Compositae ent-kaurenoids.

Synthesis and Crystal Structure of Bis-(2,2' bipyridyl)-2-pyrimidinethiolate-Ni(Ⅱ) Complex

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Chinese Journal of Structural Chemistry 2003年第2期22卷 179-181页

作者：陈燕丹张礼仪陈忠宁 State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China

The reaction between [Mn(bpy)2(MeOH)2](SbF6)2 (bpy = 2,2-bipyridine) and (Et4N)[Ni(pymt)3] (pymt = pyrimidine-2-thiolate) gave the complex [Ni(bpy)2(pymt)](SbF6) which was determined by X-ray single-crystal diffraction. The structure is of monoclinic with space group C2/c, a = 25.190(2), b = 11.3178(7), c = 19.296(1) ? b = 101.364(1)? V = 5393.4(6) 3, Mr = 718.98, Dc = 1.771 g/cm3, F(000) = 2840, m = 1.845 mm-1 and Z = 8. The final refinement gave R = 0.0641 and wR = 0.1399 for 3598 observed reflections (I > 2s(I)). The nickel(Ⅱ) atom is coordinated by four N donors from two bpy in the cis-conformation and two other atoms of S and N from one pymt, forming a distorted coordination octahedron.

关键词： nickel bipyridine pyrimidine-2-thiolate crystal structure

Synthesis and Crystal Structure of a One-dimensional Azido-bridged Manganese (II) Compound [Mn(N_3)_2(H_2O)_3·C_6H_(12)N_4]_n

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Chinese Journal of Structural Chemistry 2006年第2期25卷 135-138页

作者： CHEN Hui WANG Wen-Guo ZHANG Xiao-Feng CHEN Chang-Neng LIU Qiu-Tian 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 new one-dimensional azido-bridged manganese compound has been prepared and structurally characterized by X-ray diffraction. The complex [Mn（N3）2（H2O）3·C6H12N4]n crystallizes in space group Pnma with a = 6.5252 （5）, b = 9.3226（7）, c = 22.2070（15） ,A°, V= 1350.89（17） ,A°^3, Z = 4, Mr = 333.24, Dc = 1.639 g/cm^3, μ = 1.005 mm^-1 and F（000） = 692. The final refinement gave R = 0.0328 and wR = 0.0777 for 1085 observed reflections with I 〉 2σ（I）. The structure contains [Mn（N3）2（H2O）3]n polymeric chains and uncoordinated hexamethylenetetramine （HMTA） molecules with Mn/HMTA molar ratio of 1：1. The Mn atoms are bridged by end-to-end azido ligands to construct one-dimensional zig-zag infinite chains. Each Mn atom is six-coordinated by three N atoms of three azido ligands and three water O atoms, resulting in an octahedral geometry. Extending hydrogenbonding interactions involving water O atoms, azido and HMTA N atoms link the chains and HMTA molecules into a three-dimensional network.

关键词： manganese crystal structure azide coordination polymer

Gorenstein-Projective Modules over Morita Rings

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Algebra Colloquium 2021年第3期28卷 521-532页

作者： Dadi Asefa School of Mathematical Sciences Shanghai Jiao Tong University Shanghai 200240China

Let△(φ,ψ)=(ABMA ANBB)be a Morita ring which is an Artin *** this paper we investigate the relations between the Gorenstein-projective modules over a Morita ring△(φ,ψ)and the algebras A and *** prove that if△(φ,ψ)is a Gorenstein algebra and both Ma and aN(resp.,both NB and BM)have finite projective dimension,then A(resp.,B)is a Gorenstein *** also discuss when the CM-freeness and the CM-finiteness of a Morita ring△(φ,ψ)is inherited by the algebras A and B.

关键词： Gorenstein-projective module Gorenstein algebra Morita ring CM-finite

Triply-bridged Dicopper(Ⅰ)Complex of Bis(diphenylphosphino)acetylene with a Helical Coordination Cage

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Chinese Journal of Structural Chemistry 2002年第6期21卷 605-608页

作者： HAN Lei ZHANG Li-Yi CHEN Zhong-Ning HONG Mao-Chun(State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, The Chinese Academy of Sciences, Fuzhou, Fujian 350002, China) State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences Fuzhou Fujian 350002 China

Self-organization of copper (I) ion with bridging ligand bis(diphenylphosphino)-acetylene resulted in the isolation of a dinuclear copper ( I ) complex [Cu2(μ-Ph2PC≡ CPPh2)3(MeCN)2](ClO4)2·Et2O. Structural analysis indicated the existence of a helical coordination cage, in which two copper (I) atoms are bridged triply by the linear diphosphine Ph2PC≡CPPh2 with the CuACu separation of 6.231 A. The copper (I) atom is in an approximately tetrahedral environment with a NP3 coordination chromophore. The complex crystallizes in the triclinic, space group P 1 with a = 13.8456(2), b = 16.6010(1), c = 18.9215(3) A, α = 98.289(1), β = 91.232(1), γ = 106.496(1)°, V = 4117.60(9) A3, Z = 2, C86H82Cl2N2O9P6Cu2, Mr= 1659.37, Dc= 1.338 g/cm3, F(000) = 1708, μ = 0.754 mm-1, the final R = 0.0688 and wR = 0.1940 for 11692 reflections with I>2σ(I).

关键词： bis(diphenylphosphino)acetylene cage copper crystal structure helicity