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chemical Research in Chinese Universities 2008年第3期24卷 255-259页

作者： HAN Qiu-xia WANG Chun-zhang Institute of Molecular and Crystal engineering, school of {2. and chemical engineering, henan university, kaifeng 475001. P R. china NIU Jing-yang WANG Jing-ping Basic Experiment Teaching Center School of Chemistry and Chemical Engineering Henan University Kaifeng 475001 P R. China Institute of Molecular and Crystal engineering School of Chemistry and Chemical Engineering Henan University Kaifeng 475001 P R. China

The reaction of α-H3[PW12.40] with Y（NO3）3 in the presence of DMF or DMSO leads to two complexes with the formulae {Y（DMSO）7}·PW12.40（1） and {[Y（DMF）7]2.W12.40}·PW12.40（2.. The crystal structures indicate that complex 1 consists of discrete [YLn]3＋ cations and α-Keggin heteropolyanions [PW12.40]3-, whereas, in complex 2. donor-acceptor interaction results in a cation-anion-cation triplet. In addition, the electrochemical behavior of the two complexes indicates the usual successive reduction processes of the W atoms in the anions.

关键词： Yttrium complex Crystal structure Electrochemistry study Heteropolyanion

Theoretical studies on the possible conformers and properties of tetranitrodiazidoacetylhexaazaisowurtzitane (TNDAIW)

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Science china chemistry 2004年第5期47卷 414-419页

作者： WU Yukai1, OU Yuxiang1, LIU Zhiguo1,2., LIU Jinquan1, MENG Zheng1 & CHEN Boren1 1. school of Materials Science and engineering, Beijing Institute of Technology, Beijing 100081, {2. 2. school of chemistry and chemical engineering, henan university, kaifeng 475001. china 1. school of Materials Science and engineering Beijing Institute of Technology 100081 Beijing China 2. school of chemistry and chemical engineering Henan University 475001 Kaifeng China

Tetranitrodiazidoacetylhexaazaisowurtzitane (TNDAIW) is a novel polyazapolycyclic caged polyazidonitramine explosive first synthesized in our laboratory. All of the possible con- formers of TNDAIW are optimized using both the AM1 and PM3 methods. TNDAIW is predicted to have more polymorphs than hexanitrohexaazoisowurtzitane (CL-2.). The HF/6-31G(d) level of theory is used to investigate the lowest energy structures of D-TNDAIW for both AM1 and PM3. The possible conformers of TNDAIW are predicted to be more stable than epsilon-CL-2. based on the N-NO2.bond lengths. The impact and shock sensitivities of both the possible DA- and DP-TNDAIW are lower than the corresponding ones of epsilon-CL-2.. TNDAIW with the possible conformers is estimated to be a promising novel high energy density explosive.

关键词： tetranitrodiazidoacetylhexaazaisowurtzitane, molecular modeling, impact and shock sensitivities.

Synthesis,crystal structure of a novel yttrium (Ⅲ) coordination compound supported by typical plenary Dawson cluster

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Chinese Science Bulletin 2003年第23期48卷 2585-2588页

作者： WANG Jingping, WEI Meilin & NIU Jingyang school of chemistry and {2. engineering, henan university, kaifeng 475001. china Correspondence should be addressed to Niu Jingyang (e-mail: jyniu@ ***) school of chemistry and {2. engineering Henan University Kaifeng China

A novel yttrium (III) coordination compound supported by plenary Dawson cluster, [Y(NMP)5(H2.)2. [Y(NMP)4(H2.)2.P2.o18O62.] · NMP · 5.5 H2., (NMP = N-methyl-2.pyrrolidone) has been synthesized by reaction of α-H6P2.o18O62.· nH2., Y2.3 and NMP in water. The results of the single crystal X-ray diffraction analyses show the title compound forms a neutral and discrete cluster through [P2.o18O62.6−] being coordinated to [Y(NMP)4(H2.)2.3+ through its terminal oxygen atom.

关键词：晶体结构钇 X射线衍射分析氧原子

Synthesis,characterization,properties and crystal structure of heterometallic 1D coordination polymers {[CuLZn·CuLZn(H_2.)]·H_2.}_n

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Science china chemistry 2006年第4期49卷 338-344页

作者： TAO Ruojie1, LI Fu’an1, ZANG Shuangquan1, CHENG Yanxiang2.& NIU Jingyang1 1. chemistry and chemical {2. College of henan university, kaifeng 475001. china 2. Changchun Institute of Applied chemistry, Chinese Academy of Sciences, Changchun 13002., china 1. chemistry and chemical {2. College of henan university Kaifeng 475001 China 2. Changchun Institute of Applied chemistry Chinese Academy of Sciences Changchun 130022 China

Copper-zinc heterometallic 1D chain coordination polymer has been synthesized and characterized by elemental analysis, and IR spectra etc. The crystal structure was determined by single-crystal X-ray diffraction analyses. The title complex is 1D chain coordination polymer with the chemical formula {[CuLZn·CuLZn(H2.)]·H2.}n, where H4L=N-(2.hydroxybenzamido)-N’-(3-carboxy- lsalicylidene)ethylenediamine. Its structural unit is comprosed of two tetranuclear cycles formed by two dissymmetrical tetranuclear units. These units polymerized each other to form 1D chain coordi- nation polymer.

关键词： copper, zinc, heterometallic coordination polymer, crystal structure.

Size effect of fullerene cages and encaged clusters in M3N@C2.

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Science china chemistry 2009年第5期52卷 584-589页

作者： GAN LiHua school of chemistry and {2. engineering, Southwest university, Chongqing 400715, china school of chemistry and {2. engineering Southwest University Chongqing 400715 China

Based on the calculated findings that the sizes of encaged clusters determine the structures and the stability of C80-based trimetallic nitride fullerenes (TNFs), more extensive density functional theory calculations were performed on M3N@C68, M3N@C78 and M3N@C80 (M=Sc, Y and La). The calculated results demonstrated that the structures and stability undergo a transition with the increasing of the sizes of the cages and clusters. Sc3N is planar inside the three considered cages, Y3N is slightly pyramidal inside C68-6140 and C78-5 and planar inside I h C80-7, however, La3N is pyramidal inside all the three cages. Those cages with pyramidal clusters inside deformed considerably, compared with their parent cages. In these cases, the bonding of metallic atoms toward the cages does not play an impor-tant role, and the encaged cluster tends to be located inside the cages with the largest M-M and M-C distances so that the strain energy can be released mostly. These calculations revealed the size effect of fullerene cages and encaged clusters, and can explain the position priority of M3N inside fullerene cages and the differences in yield of M3N@C2..

关键词： trimetallic nitride fullerenes (TNFs) density functional theory (DFT) size effect stability

Theoretical study of bifurcated bent blue-shifted hydrogen bonds CH_2.Y

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Science china chemistry 2008年第7期51卷 623-631页

作者： LI AnYong school of chemistry and {2. engineering, Southwest university, Chongqing 400715, china school of chemistry and {2. engineering Southwest UniversityChongqing 400715China

Ab initio quantum chemistry methods were applied to study the bifurcated bent hydrogen bonds Y… H2.Z (Z = O, S, Se) and Y…H2.Z2.(Z = F, Cl, Br) (Y = Cl-, Br-) at the MP2.6-311++G(d,p) and MP2.6-311++G(2.f,2.) levels. The results show that in each complex there are two equivalent blue-shifted H-bonds Y…H—C, and that the interaction energies and blue shifts are large, the energy of each Y…H—C H-bond is 15-2. kJ/mol, and Δr(CH) = -0.1 - -0.5 pm and Δv(CH) = 30 - 80 cm-1. The natural bond orbital analysis shows that these blue-shifted H-bonds are caused by three factors: large rehybridization; small direct intermolecular hyperconjugation and larger indirect intermolecular hy- perconjugation; large decrease of intramolecular hyperconjugation. The topological analysis of elec- tron density shows that in each complex there are three intermolecular critical points: there is one bond critical point between the acceptor atom Y and each hydrogen, and there is a ring critical point inside the tetragon YHCH, so these interactions are exactly H-bonding.

关键词： bifurcated bent H-bonds blue-shifted H-bonds topological property of electron density intramolecular hyperconjugation

Boron rings containing planar octa- and enneacoordinate cobalt, iron and nickel metal elements

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Science china chemistry 2008年第7期51卷 607-613页

作者： LUO Qiong school of chemistry and {2. engineering, Central South university, Changsha 410083, china school of chemistry and {2. engineering Central South UniversityChangsha 410083China

For a series of boron rings with planar hyper-coordinate 8th group transition metal atoms, singlet 1FeB8-2. multiplet kFeB9n (n = -1, k = 1; n = 0, k = 2., singlet 1CoB8n(n = -1, +1, +3), multiplet kCoB9n (n = +1, k = 2. n = 0, k = 1) and singlet 1NiB9+, the geometry structures have been optimized to be local minima on corresponding potential hyper-surfaces. The electron structures are discussed by orbital analysis and the aromaticity is predicted by nucleus-independent chemical shifts calculation at both the B3LYP/6-311+G* and BP86/6-311+G* levels of theory, respectively. The results suggest that all these structures with high symmetry planar geometries are stable and have aromatic properties with six π valence electrons.

关键词： planar hyper-coordinate transition metal DFT

Influence of NH_3-treating temperature on visible light photocatalytic activity of N-doped P_(2.)-TiO_2

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Science china chemistry 2009年第8期52卷 1164-1170页

作者： CHEN WeiPing1,2.WANG Yan1,JIN ZhenSheng1,2.FENG CaiXia1,WU ZhiShen1 & ZHANG ZhiJun1 1 Key Laboratory for Special Functional Materials,henan university,{2. 475004,china 2.College of chemistry and chemical engineering,henan university,{2. 475004,china Key Laboratory for Special Functional Materials Henan University Kaifeng 475004 China College of chemistry and chemical {2. Henan University Kaifeng 475004 China

The influence of NH3-treating temperature on the visible light photocatalytic activity of N-doped P2.-TiO2.as well as the relationship between the surface composition structure of TiO2.and its visible light photocatalytic activity were *** results showed that N-doped P2.-TiO2.treated at 600℃ had the highest *** structure of P2.-TiO2.was converted from anatase to rutile at 700℃.Moreover,no N-doping was detected at the surface of *** was no simply linear relationship between the visible light photocatalytic activity and the concentration of doped nitrogen,and visible light *** visible light photocatalytic activity of N-doped P2.-TiO2.was mainly influenced by the synergistic action of the following factors:(i) the formation of the single-electron-trapped oxygen vacancies(denoted as Vo);(ii) the doped nitrogen on the surface of TiO2.(iii) the anatase TiO2.structure.

关键词： P2.-TiO2 nitrogen doping NH3 treatment photocatalysis visible light photocatalytic activity

The resonance Rayleigh scattering of the interaction of copper(Ⅱ)-bleomycinA2.with DNA and its analytical application

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Science china chemistry 2010年第3期53卷 618-624页

作者： LIU JiangTao1,LIU ShaoPu2.& LIU ZhongFang2.1school of chemistry,Chongqing Normal {2.,Chongqing 400300,china 2.0} of chemistry and chemical engineering,Southwest {2.,Chongqing 400715,china school of chemistry Chongqing Normal University Chongqing China school of chemistry and {2. engineering Southwest University Chongqing China

The forming of bleomycinA2.Cu(Ⅱ) cationic chelate and the interaction of the chelate with DNA have been investigated by using resonance Rayleigh scattering(RRS),molecular absorption and fluorescence *** result shows that in aqueous solution,bleomycinA2.BLMA2. can react with Cu(Ⅱ) to form 1:1 cationic chelate which contributes to the changes of the absorption spectra and the quenched fluorescence of *** the cationic chelate further bound with DNA to form ternary ion-association complexes,the remarkable enhancement of the RRS intensity was *** this work,the optimum conditions for the coordination reaction of BLMA2.with Cu(Ⅱ) and some influencing factors have been *** reaction mechanism of BLMA2.Cu(Ⅱ) binding with DNA was suggested and a binding model was *** addition,the fluorescence quenching type of BLMA2.was investigated.A highly sensitive,simple and rapid new method for the determination of DNA by using BLMA2.Cu(Ⅱ) as RRS probe has been *** detection limits(3σ) are 7.2.ng/mL for ctDNA,7.1 ng/mL for sDNA and 18 ng/mL for *** method can be applied to the determination of trace amounts of DNA.

关键词： bleomycinA2 Cu(Ⅱ) DNA resonance Rayleigh scattering fluorescence quenching

Influence of steric and intramolecular inductive effects on the variable trends in R-X (R=Alkyl) bond dissociation energy

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Science china chemistry 2009年第7期52卷 943-951页

作者： CAO ChenZhong school of chemistry and {2. engineering, Hunan university of Science and Technology, Xiangtan 4112.1, china school of chemistry and {2. engineering Hunan University of Science and Technology Xiangtan 411201 China

The question "why are the variation trends of R-X bond dissociation energy different?" is answered. The R-X bond dissociation energy (BDE) may be influenced by three main factors: the C-X intrinsic bond energy, the 1,3 geminal repulsion, and the intramolecular charge-induced dipole. In the presence of atom X, the variation trend of BDE in R-X (R= Me, Et, i-Pr, t-Bu) is dominated by two factors, the 1,3 geminal repulsion and the intramolecular charge-induced dipole. The former decreases the R-X BDE, and the latter either increases or decreases the R-X BDE. For the series of R-X with the R-C bond (such as R-Me, R-CH == CH2. R-C≡CH, and R-CN), the 1,3 geminal repulsion decreases the R-X BDE, and the variation trends of R-C BDE decrease from Me to t-Bu. As regards the series of R-X (such as R-H, R-BH2. and R-SiH2. in which the electronegativity of atom X is smaller than that of the carbon atom, the above two factors decrease the R-X BDE, and the variation trends of the R-X BDE decrease from Me to t-Bu. As to the series of R-X (such as R-F, R-OH, R-Cl, R-Br, R-I, and R-NH2. in which the electronegativity of atom X is larger than that of the carbon atom, the 1,3 geminal repulsion decreases the R-X BDE, while the intramolecular charge-induced dipole increases the R-X BDE. In this case, the variation trends of R-X BDE depend on the competition of the two factors. As a result, some of them (e. g., R-F, R-OH) increase from Me to t-Bu, some (e. g., R-I) decrease from Me to t-Bu, and some (e. g., R-Br) change very little.

关键词： bond dissociation energy charge-induced dipole geminal repulsion ionic configuration