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Investigation on Vibrational Spectra and Structures of 4-Mercaptopyridine Monomer and Its Dihydrate

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Chemical Research in Chinese Universities 2006年第1期22卷 90-93页

作者： CHENG Jian-bo 1,2., XUE Wei-qing 1 , ZHAO Bing 1** , ZHANG Gang 3.and GONG Bao-an 2.1. key {2. for Supramolecular Structure and Material of Ministry of Education, jilin University, {3. 130012. P. R. china 2. Science and Engineering College of Chemistry and Biology, Yantai University, Yantai 2.4005, P. R. china 3. state key {2. of Theoretical and Computational Chemistry, jilin University, {3. 13.02.0} P. R. china [a]key laboratory for Supramolecular Structure and Material of Ministry of Education Jiln University Changchun 130012 P. R. China[b]Science and Engineering College of Chemistry and Biology Yantai University Yantai 264005 P. R. China[c]State Key Laboratory of Theoretical and Computational Chemistry Jiln University Changchun 130023 P. R. China

The optimized molecular structures and vibrational frequencies of 4-mercaptopyridine(4MPY) monomer and its dihydrate were studied by means of the density functional theory(DFT), viz. B3.YP method with the 6-3.1++G(d,p) basis set. On the basis of the calculations, the assignments of the vibrational spectra of the monomer and the dihydrate were performed, and so were investigated the changes in the structure and the vibrational spectrum of the dihydrate as well as the intermolecular force resulting in the formation of the dihydrate. The calculated results show that each of the water molecule planes is vertical to the pyridine ring plane in the dihydrate that is formed via the H-bonds between 4MPY and water molecules. Furthermore, the structure and the vibrational spectrum of 4MPY can be consi- derably affected by the water molecules.

关键词： 4MPY Dihydrate Vibrational spectra DFT Molecular structure

Effect of solution concentration on the structured order and optical properties of short-chain polyene biomolecules

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Science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 1646-1650页

作者： OUYANG ShunLi1,2.SUN ChengLin1,2.ZHOU Mi1,2.LI DongFei2.WANG WeiWei1,2.QU GuanNan1,LI ZuoWei1,2.GAO ShuQin1 & YANG JianGe3.1 state {2. laboratory of {3. materials,jilin University,changchun 130012.china 2.College of Physics,jilin University,changchun 13.02.0}china 3.The ordnance Engineering Department,Air Force Aviation University,changchun 13.02.,china 1. state key {2. of {3. materials Jilin University Changchun 130012 China2. College of Physics Jilin University Changchun 130023 China3. The ordnance Engineering Department Air Force Aviation University Changchun 130022 China

We have measured the Raman spectra and UV-Vis absorption spectra of linear polyene biomolecules(β-carotene and lycopene) in CS2.at low concentrations(10-6-10-10 mol/L).With decreasing concentration,all the carbon-carbon vibrations form a coherent mode in ordered β-carotene and lycopene due to extended π-conjugation that gives strong electron-phonon coupling,which leads to an anomalous experimental *** observed an extremely high Raman scattering cross section(RSCS) and the Raman activities in β-carotene and lycopene are characterized by intensive overtones and ***,the UV-Vis absorption bands become narrower.

关键词： molecular structured order Raman spectroscopy Raman scattering cross section

superhard nano-multilayers and nanocomposite coatings

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Progress in Natural Science:materials International 2005年第2期15卷 2-12页

作者： BAI Xiaoming, ZHENG Weitao* and AN Tao(Department of Material Science and key laboratory of Automobile of MOE, {2. University,{3.) Department of Material Science and key laboratory of Automobile of MOE Jilin University Changchun 130012 China

This paper reviews the recent development of nano-multilayers and nanocomposite coatings. The hardening mechanisms and design of hard coating are discussed in details. Recent research on Ti/TiN and nitride/nitride multilayer, Ti-Si-N and Ti-Al-Si-N nanocomposite coatings is described, and the perspectives of the related research are proposed.

关键词： nano-structured materials multilayer nanocomposite hardness

Experimental remolding on the caprock's 3. strain field of the Indosinian-Yanshanian epoch in Tongling deposit concentrating area

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Science china Earth Sciences 2005年第7期48卷 863-874页

作者： DENG Jun1,HUANG Dinghua2.WANG Qingfei1,WAN Li1,SUN Zhongshi3.YANG Liqiang1 & GAO Bangfei1 1. state {2. laboratory of Geological Processes and Mineral Resources,{3. University of Geosciences,Beijing 100083.{3. 2. Faculty of Earth Sciences,{3. University of Geosciences,Wuhan 43.074,{3. 3. Department of Earth Sciences,jilin University,{12. 13.061,{3. state key {2. of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China Department of Earth Sciences Jilin University Changchun 130061 China

Based on field observations and rheology analysis, we perform one analogue experiment and remold the 3. structural frame of Tongling deposit concentrating area firstly. Then we disassemble and dialyze the 3. structures of the model using the methods of "slicing" and "stripping". A series of sliced planes vertical to the fold hinges show similar landscapes of that in the drill hole profiles. Meanwhile, layer stripping analysis indicates that the deformation features of each layer in the model are qualitatively analogical to those obtained from field observations. Through contrasting the 3. structure between the experimental model and the field phenomena, we verify the following 3. deformation features of the caprock in this area: (1) the Tongling area mainly consists of three series of NE S-typed fold groups; (2. in the uniform stress field, the incoherent folds universally develop in different positions, along different axes as well as in different strata; (3. the faults propagate upward which are mostly inter-bedded detachment faults, while the fold amplitudes decrease while going deeper; and (4) the folds and cleavages are highly developed in the Silurian System indicating that the deformation effect of the Indosin-ian-Yanshanian structural layer terminates at this layer, which suggests that the Silurian System is the crucial layer for the inversion between brittle and plastic deformation domains and the underlying strata are subject to the control of another deformation system with distinct properties.

关键词： Tongling deposit concentrating area Indosinian-Yanshanian epoch 3. structural frame of the caprock analogue experiment slicing and stripping analysis structural model.

Structures and stability of isomers of[C,N,N,P]system

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Science china Chemistry 2005年第5期48卷 415-423页

作者： KAN Wei1,2. ZHONG Hua1, YU Haitao1, FU Honggang1,3.& SUN Jiazhong1,3.1. School of Chemistry and {2. Science, Heilongjiang University, Harbin 150080, china 2. School of Chemistry and Chemical Engineering, Qiqihar University, Qiqihar 161006, china 3. {3. key laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, jilin University, changchun 13.02.0} china 1. School of Chemistry and materials Science Heilongjiang University 150080 Harbin China 2. School of Chemistry and Chemical Engineering Qiqihar University 161006 Qiqihar China 3. jilin University State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry 130023 Changchun China

Nine isomers, twenty transition states, and some relative dissociation fragments of [C,N,N,P] system were located at the B3.YP/6-3.1G(d) and QCISD(t)/6-3.1+G(2.f) (single-point) levels of theory, and the isomerization, structures, and stability of these obtained isomers were suggested. The results indicate that four nonlinear chainlike isomers NCNP, NCPN, CNPN, and CNNP with 2.′ electronic state are kinetically stable. Other isomers are kinetically unstable to-wards isomerization or dissociation because of the corresponding smaller reaction barriers. Furthermore, calculated vibrational frequencies, rotational constants, dipole moments, the first adiabatic ionization energies, and adiabatic electron affinities of the four isomers may provide some theoretical information that is helpful for identifying their existence in future laboratory and interstellar investigations. The results are also compared with [Si,N,N,P] system.

关键词： potential energy surface, [C,N,N,P] system, isomerization, kinetic stability.

Thermal behavior and phase behavior in blends of liquid crystalline poly(aryl ether ketone) and poly(aryl ether ether ketone) containing thioether units

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Science china Chemistry 2012年第4期55卷 612-617页

作者： LI Ye1, CHEN Jian2. LIU XinCai1 & YANG DeCai2.1Alan G. MacDiarmid Institute, jilin University, changchun 130012. china 2.2. {3. laboratory of Polymer Physics and Chemistry changchun Institute of Applied Chemistry, Chinese Academy of Sciences, changchun 13.02., china 1. Alan G. MacDiarmid Institute Jilin University Changchun 130012 China2. State Key Laboratory of Polymer Physics and Chemistry changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China

Thermal behavior and phase behavior in blends of liquid crystalline poly(aryl ether ketone) with lateral methoxy groups (M-PAEK) and poly(aryl ether ether ketone) containing thioether units (S-PEEK) have been investigated by differential scanning calorimetry (DSC) and polarized light microscopy (PLM) techniques. The results indicate that the composition of the blends has great effect on the phase behavior and morphology. Thin films of pure M-PAEK and S-PEEK crystallized from the melts exhibit typical mosaic and spherulitic structures, respectively. For the blends with higher M-PAEK contents (> 50%), an unusual ring-banded spherulite with structural discontinuity is formed. The bright core and rings of the ring-banded spherulites under PLM are composed of M-PAEK phase, while the dark rings consist mainly of S-PEEK phase. For the 50:50 M-PAEK/S-PEEK blend, the ring-banded spherulites and S-PEEK spherulites coexist, which implies that a partial phase separation between the two components takes place in the melting state. In S-PEEK-rich blends, a volume-filled spherulite is produced. In addition, the effect of isothermal crystallization temperature on the phase behavior, especially the ring-banded spherulite formation in the blends, is discussed.

关键词： liquid crystalline poly(aryl ether ketone) – poly(aryl ether ether ketone) containing thioether units – phase behavior – rhythmically grown ring banded spherulite

Highly stereospecific polymerization of isoprene with homogeneous binary Ziegler-Natta catalysts based on NCN-pincer neodymium precursor

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Science china Chemistry 2010年第8期53卷 1641-1645页

作者： LIU DongTao1,2.CUI DongMei1 & GAO Wei3.1state {2. laboratory of Polymer Physics and Chemistry {3. Institute of Applied Chemistry,Chinese Academy of Sciences,{3. 13.02.,china 2.raduate University of Chinese Academy of Sciences,Beijing 10003.,china 3.chool of Chemistry,jilin University,{3. 130012.china 1. state key {2. of Polymer Physics and Chemistry changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China2. Graduate University of Chinese Academy of Sciences Beijing 100039 China3. School of Chemistry Jilin University Changchun 130012 China

The aryldiimine NCN-pincer stabilized neodymium dichloride combined with aluminum alkyls established a new type of homogeneous binary neutral Ziegler-Natta catalyst *** system exhibited high activity and high cis-1,4 selectivity for the polymerization of isoprene (Tp=2. °C,98.2.;Tp=-2. °C,> 99%).Such catalytic performances remained under a broad range of polymerization temperatures and monomer-to-neodymium ratios (from 500 to 8000),reaching high number-average molecular weight (Mn=1582.kg/mol) and relatively narrow molecular weight distribution (PDI=1.68),which was,however,influenced by the amount and bulkiness of aluminum *** investigation of the polymerization was performed,which showed the number-average molecular weight of the resultant polyisoprene had an almost linear correlation with the conversion,suggesting,in some degree,the polymerization with this catalytic system was controllable.

关键词： neodymium cis-1 4 selectivity NCN-pincer complex polyisoprene

Theoretical studies on Ru(fppz)_2.CO)L (L=N-heterocyclic ligand):Electronic structure,absorption,phosphorescence,and solvatochromism

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Science china Chemistry 2008年第12期51卷 1211-1220页

作者： LIU Tao1, ZHOU Xin1, BAI FuQuan1, ZHANG JianPo1, XIA BaoHui1,2. PAN QingJiang3.& ZHANG HongXing1 1 state {2. laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, {3. University, changchun 13.02.0} china 2.College of Chemistry, {3. University, changchun 13.02.0} china 3.laboratory of Physical Chemistry, School of Chemistry and materials Science, Heilongjiang University, Harbin 150080, china state key {2. of Theoretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University Changchun 130023 China College of Chemistry Jilin University Changchun 130023 China laboratory of Physical Chemistry School of Chemistry and Materials Science Heilongjiang University Harbin 150080 China

A series of ruthenium(II) complexes Ru(fppz)2.CO)L [fppz = 3.trifluoromethyl-5(2.pyridyl)pyrazole; L = pyridine (1), 4-dimethylaminopyridine (2., 4-cyanopyridine (3.] were designed and investigated theo-retically to explore their electronic structures, absorption, and emissions as well as the solvatochrom-ism. The singlet ground {2. and triplet excited {2. geometries were fully optimized at the B3.YP/LANL2.Z and CIS/LANL2.Z level, respectively. The HOMO of 1-3.is composed of dyz(Ru) atom and π(fppz). The LUMO of 1 and 2.is dominantly contributed by π*(fppz) orbital, but that of 3.is con-tributed by π*(L). Absorption and phosphorescence in vacuo, C6H12. and CH3.N media were calculated using the TD-DFT level of theory with the PCM model based on the optimized ground and excited {2. geometries, respectively. The lowest-lying absorption of 1 and 2.at 3.7 and 3.1 nm is attributed to {[dyz(Ru) + π(fppz)] → [π*(fppz)]} transition, but that of 3.at 479 nm is assigned to {[dyz(Ru) + π(fppz)] → [π*(L)]} transition. The phosphorescence of 1 and 2.at 43. and 43. nm originates from 3.[dyz(Ru) + π(fppz)] [π*(fppz)]} excited {2., while that of 3.at 606 nm is from 3.[dyz(Ru) + π(fppz)] [π*(L)]} excited {2.. The calculation results showed that the absorption and emission transition character can be changed from MLCT/ILCT to MLCT/LLCT transition by altering the substituent on the L ligand. The phosphorescence of 1 and 2.does not have solvatochromism, but that of 3.at 606 nm (vacuo), 584 nm (C6H12., and 541 nm (CH3.N) is strongly dependent on the solvent polarity, so introducing elec-tron-withdrawing group on ligand L will induce remarkable solvatochromism.

关键词： ruthenium complex DFT phosphorescence solvatochromism

Comparison of photovoltaic devices based on MEH-PPV with various molecular weights

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Chinese Science Bulletin 2004年第21期49卷 2259-2261页

作者： KANG Bonan1,2. WANG Liduo1, YANG Yong1 & QIU Yong1 1. key laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua Univer- sity, Beijing 100084, {2. 2. {3. key laboratory on Integrated optoelectronics, jilin University Region, changchun 13.02.3} {2. key laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education Department of Chemistry Tsinghua University Beijing 100084 China

Polymer photovoltaic devices based on poly (2. methoxy-5-(2. -ethyl-hexyloxy)-1,4-phenylene vinylene) (MEH- PPV) with three weight-average molecular weights (Mw) have been fabricated with the device structure of ITO/PEDOT/ MEH-PPV/Ca/Ag, and the effect of the molecular weight on photovoltaic properties has been investigated. The experi- mental results show that the high molecular weight of MEH- PPV leads to low series resistance (Rs) and high short-circuit current. The low molecular weight of MEH-PPV leads to high shunt resistance (Rsh) and high open-circuit voltage. When the molecular weight is 6×105, the highest power con- version efficiency was observed.

关键词： MEHPPV 分子量光电器件载流子迁移率串联电阻并联电阻聚(2.甲氧基-5-(2.-乙基-乙氧基)-1,4-亚苯基乙烯撑)