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Theoretical Studies on the molecular structures and Thermodynamic Properties of Polychlorinated Acenaphthylenes

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Chinese Journal of Structural Chemistry 2011年第3期30卷 300-307页

作者：曾小兰张秀兰张义东姜永 College of Chemistry and Chemical Engineering Xinyang Normal University

Geometric structures of 135 polychlorinated acenaphthylene （PCAC） molecules were optimized using density functional theory （DFT） at the B3LYP/6-311G^＊＊ level and some thermodynamic properties of them in the ideal gas state were calculated. The relations of these thermodynamic properties with the number and position of chlorine atoms were also explored, from which the relative stability of PCAC congeners was theoretically proposed according to the magnitude of the relative standard Gibbs free energy of formation （△r,fGθ）. The results show that all PCAC isomers have planar geometric configuration. There exists intramolecular Cl···Cl weak interaction in some PCAC molecules. The change of △fHθ and fGθ of most stable PCAC isomers with increasing the number of chlorine atoms is different from that in the least stable PCAC congeners. The values of fHθ and fGθ for PCAC isomers with the same number of chlorine atoms show a strong dependence on the position of chlorine atoms and the relative stability of PCAC congeners has close relation with the intramolecular Cl···Cl nuclear repulsive interaction.

关键词： polychlorinated acenaphthylenes (PCACs) molecular structures thermodynamicproperties relative stability density functional theory (DFT)

Theoretical Studies on the molecular structures and Thermodynamic Properties of Polychlorinated Fluorenes

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Chinese Journal of Structural Chemistry 2010年第4期29卷 647-654页

作者：曾小兰张秀兰王岩陈东辉 College of Chemistry and Chemical Engineering Xinyang Normal University

Geometric structures of 135 polychlorinated fluorene （PCFR） molecules were optimized using density functional theory （DFT） at the B3LYP/6-311G＊＊ level and their thermodynamic properties in the ideal gas state were calculated. The relations of these thermodynamic properties with the number and position of chlorine atoms were also explored, from which the relative stability of PCFR congeners was theoretically proposed according to the magnitude of the relative standard Gibbs free energy of formation （Δr,fGθ）. The results show that the geometric configuration of PCFR isomers is determined by the position of chlorine atoms. There exist two types of intramolecular weak interactions, i.e., C–H···Cl and Cl···Cl interactions in PCFR molecules. The change of ΔfHθ and ΔfGθ of most stable PCFR isomers with increasing the number of chlorine atoms is different from that in most unstable PCFR congeners. The values of ΔfHθ and ΔfGθ for PCFR isomers with the same number of chlorine atoms strongly depend on the position of chlorine atoms and the relative stability of PCFR congeners is mainly determined by intramolecular delocalized π bond and Cl···Cl nuclear repulsive interaction.

关键词： polychlorinated fluorenes (PCFRs) molecular structures thermodynamic properties relative stability density functional theory (DFT)

Crystal structures of (Z)-1-Phenyl-1-phenylseleno- 2-(p-tolylsulfonyl)ethene and (Z)-1,3-Diphenyl-3- phenyl-seleno-2-(p-tolylsulfonyl)-2-propen-1-ol

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Chinese Journal of Structural Chemistry 2004年第6期23卷 543-546页

作者： XIEMei-Hua HUANGXian DepartmentofChemistry ZhejiangUniversity（XixiCampus）Hangzhou310028China

The molecular structures of compounds (Z)-1-phenyl-1-phenylseleno-2-(p-tolyl- sulfonyl) ethene 1 (C21H18O2SSe, Mr = 413.37) and 1,3-diphenyl-3-phenylseleno-2-(p-tolylsulfonyl) -2-propen-1-ol 2 (C28H24O3SSe, Mr = 519.49) were determined by single-crystal X-ray diffraction analyses. Crystal 1 crystallizes in monoclinic, space group P21/n with a = 12.574(4), b = 12.087(3), c = 13.132(4) , b = 107.973(4), V = 1898.5(9) ?, Z = 4, Dc = 1.446 g/cm3, m = 2.098 mm-1, l = 0.71073 ? F(000) = 840, R = 0.0484 and wR = 0.1085. Crystal 2 crystallizes in monoclinic, space group P21/n with a = 7.0710(4), b = 14.6604(9), c = 24.3432(5) ? b = 94.76(1), V = 2514.8(3) 3, Z = 4, Dc = 1.372 g/cm3, m = 1.603 mm-1, l = 0.71073 ? F (000) = 1064, R = 0.0366 and wR = 0.0573. The X-ray diffraction analysis shows that both of the title compounds are in Z- configuration.

关键词： molecular structures z-configuration phenylseleno p-tolylsulfonyl

Board-invited review: Sensitivity and responses of functional groups to feed processing methods on a molecular basis

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Journal of Animal Science and Biotechnology 2013年第1期4卷 1-4页

作者： Peiqiang Yu Department of Animal and Poultry Science College of Agriculture and BioresourcesUniversity of Saskatchewan 农业部

In complex feed structures, there exist main chemical functional groups which are associated with nutrient utilization and availability and functionality. Each functional group has unique molecular structure therefore produce unique molecular vibration spectral profile. Feed processing has been used to improve nutrient utilization for many years. However, to date, there was little study on processing-induced changes of feed intrinsic structure and functional groups on a molecular basis within intact tissue. This is because limited research technique is available to study inherent structure on a molecular basis. Recently bioanalytical techniques： such as Synchrotron Infrared Microspectroscopy as well as Diffuse Reflectance Infrared Fourier Transform molecular spectroscopy have been developed. These techniques enable to detect molecular structure change within intact tissues. These techniques can prevent destruction or alteration of the intrinsic protein structures during processing for analysis. However, these techniques have not been used in animal feed and nutrition research. The objective of this review was show that with the advanced technique, sensitivity and responses of functional groups to feed processing on a molecular basis could be detected in my research team. These functional groups are highly associated with nutrient utilization in animals.

关键词： Sensitivity and responses of functional groups molecular structures Feed processing Nutrient utilizationand availability

Model construction of the macromolecular structure of Ningdong Coal

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Model construction of the macromolecular structure of Ningdo...

Synthesis of the Ionic Organotin Compounds by the Reaction of PhnSnCl4-n (n=1, 2, 3) with HSCH2COOH

第十三届全国量子化学会议

作者： Zhuangmei Li Ping Li Hongcun Bai State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering Ningxia University

Deeper understanding of the molecular structure is one of the key to realize the clean utilization of coal. Hence, the research of coal structure is the core and leading-edge topic in coal science. Ningdong energy-chemical industry base that located in Ningxia of northwest China is one of the most large-scale coal bases of China in recent decade. In order to choose more suitable coal utilization technology, a kind of coal from Ningdong coalfield was first determined by the ultimate analysis and proximate anslysis. Then its vitrinite was got by sink-float centrifugation, and was analyzed via FTIR, PXRD, XPS and13 C NMR to get the feature information of group components framework structure. The results indicate that the benzene and naphthalene structures are the main forms of aromatic carbon in the coal. Macromolecular structure is given priority to with three and four replace benzene ring,twenty eight O atoms are present as carboxyl, carbonyl and hydroxyl groups and two N atoms exist in the forms of pyridine and pyrrole. And the structure of the coal was simulated and optimized with Gaussian09 software. The calculated NMR and the IR spectra of the framework structure model are well consistent with that of the experimental. So the structural formulas of the coal are defined as C220 H146 O28 N2. With the experiments and simulation calculation, a method is developed to construct the molecular structures so as to find common characteristics of the Ningdong coal and differences from others. It is very significative to explore the mechanism of coal conversion and provide a theoretical guide for deep processing and efficient use of coal.

关键词： Ningdong Coal molecular structures Quantum Chemistry

来源： cnki会议评论

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有机化学 2004年第Z1期24卷 207-页

作者： ZHONG,Gui-Yun SUN,Li-Juan XIE,Qing-Lan Department of Biochemistry Xingtai University Xingtai 054001 National Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071 National Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071

　　The study of ionic organotin compounds is of current attention owing to their diversified molecular structures and wide range of applications.[1～3] In this paper, we concluded our works on ionic organotin compoun... 详细信息

关键词： organotin compounds molecular structures range of

Study on Ionic Organotin Compounds Ⅲ. Synthesis of Five-Coordinated Anionic Tin(Ⅳ) Complexes and Crystal Structure of [ ( i-Pr)2NH2] [ PhSn(μ2-SCH2COO)2]

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有机化学 2003年第Z1期23卷 165-165页

作者： ZHONG Gui-Yun SUN Li-Juan XIE Qing-Lan National Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071 National Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071 National Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071

　　The study of ionic organotin compounds is of current attention owing to their diversified molecular structures and wide range of applications, such as biological activities[1 ～3] and as catalysts in organic synthesis. [4] Recently, we synthesized some new ionic organotin compounds by dephenylation reaction. [5] In this paper, we continued to study the reaction of mercaptoacetic acid with phenyltin trichloride in the presence of organic base. The reaction equation was as follows:……

关键词： Organotin Compounds organotin compounds biological activities molecular structures mercaptoacetic acid organic synthesis organic base range of

Advanced Polymeric Materials for High-tech Innovations

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Chemical Research in Chinese Universities 2001年第Z1期17卷 59-页

作者： TANG BenZhong Department of Chemistry Hong Kong University of Science Technology Clear Water Bay Kowloon

High technology is advancing our society and modernizing our life and advanced materials play an important role in the technological innovations. My research group has been working on the development of advanced polymeric materials and in this talk I will report our recent work on the creation of new conjugated polymers with novel molecular structures and unique materials properties.1-18 Our work include the design of molecular structures of monomeric building blocks, development of stable, effective and environmentally benign "green” polymerization catalysts, discovery of new polymerization reactions, synthesis of functional macromolecules, fabrication of nanodimensional composites, assembly and control of hierarchical structures, and construction of electrooptical devices. We have revealed the liquid crystallinity, light emission, photoconductivity, optical limiting, nano-hybridization, solvatochromism, optical activity, self-organization, and biological activity of the linear polyacetylenes and hyperbranched polyarylenes. The utilization of the advanced polymers and their interesting materials properties for high-tech innovations will be discussed.

关键词： molecular structures hyperbranched polyarylenes hierarchical structures environmentally benign polymeric materials conjugated polymers biological activity advanced materials building blocks