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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 laboratory for Supramolecular Structure and Material of Ministry of Education, jilin university, {3. 13.012. P. R. china 2. Science and Engineering College of Chemistry and Biology, Yantai university, Yantai 264005, P. R. china 3. state key laboratory of Theoretical and Computational Chemistry, jilin university, {3. 13.023. 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

Transition metal coordination polymers with polycarboxylic acid as bridging ligands:Synthesis and structure characterization of[Fe(μ_(4)-bta)_(0.5)(phen)(OH)]_(n)

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Science china Chemistry 2004年第1期47卷 10-16页

作者： XU Jiqing, CHU Deqing, YU Jiehui, WANG Tiegang & TANG AoqingCollege of Chemistry and state key laboratory of Inorganic Synthesis and Preparative Chemistry,{3., changchun 13.023. china Institute of Theoretical Chemistry,{3., changchun 13.023. china 1. College of Chemistry and state key laboratory of Inorganic Synthesis and Preparative Chemistry Jilin University 130023 Changchun China 2. Institute of Theoretical Chemistry Jilin University 130023 Changchun China

A new 2D (two-dimensional) coordination polymer, [Fe(μ4-bta)o.5(phen)(OH)]n (1), has been hydrothermally synthesized with FeCl3.6H2, Na4bta (h4bta = 1,2,4,5-benzentetracarboxylic acid), 1,10-phen (1,10-phenanthroline) and H2O as raw materials. The crystals of the compound belong to monoclinic P21/n space group, a = 1.0129(2) nm, b = 0.9265(2) nm, c = 1.5696(3. nm, β=91.3.(3.°V=1.4721(5) nm3.Z=3. final R1=0.0292, wR 2=0.0798 for 2572 [/>2σ(/)] observed reflections. The result of structure determination shows that in the compound each bta ligand is connected with four Fe3. forming a new μ4-coordination mode. Four deprotonated carboxylic groups of bta link to Fe3.ions alternatively through monodentate and bidentate coordination fashion, constructing 2D layer network. The measurement of variable temperature magnetic susceptibility indicates that there exist antiferromagnetic interactions between Fe3.ions in the compound. The TGA spectrum displays relatively fine thermal stability of the compound. In addition, IR and UV-Vis spectra of compound 1 have also been measured.

关键词： 2D coordination polymer, 1,2,4,5-benzentetracarboxylic acid, iron, hydrothermal synthesis, crystal structure.

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 key laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry,{3., changchun 13.023. china 2 College of Chemistry,{3., changchun 13.023. china 3.laboratory of Physical Chemistry, School of Chemistry and materials Science, Heilongjiang university, Harbin 150080, china state key laboratory 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 state and triplet excited state geometries were fully optimized at the B3.YP/LANL2DZ and CIS/LANL2DZ 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 state 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 state, while that of 3.at 606 nm is from 3.[dyz(Ru) + π(fppz)] [π*(L)]} excited state. 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

Theoretical studies on the spectroscopic properties and the substituent effects of pyridyl triazole Os(Ⅱ) complexes

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Science china Chemistry 2009年第3期52卷 261-265页

作者： WU YuHui, ZHOU Xin & ZHANG HongXing state key laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry,{3., changchun 13.023. china 1. state key laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University Changchun 130023 China

To explore the spectroscopic properties of pyridyl triazole Os(Ⅱ) complexes and how the substituent effects affect the spectroscopic properties of [Os(ptz)2L2] (L=PH3. ptzH=(2-pyridyl)-1,2,4-triazole) (1), [Os(bptz)2L2] (bptzH=3.tert-butyl-5-(2-pyridyl)-1,2,4-triazole) (2), [Os(fptz)2L2] (fptzH=3. (trifluoreomethyl)- 5-(2-pyridyl)-1,2,4-triazole) (3., and [Os(fbtz)2L2] (fbtzH=3.(trifluoreomethyl)-5-(4-tert-butyl- 2-pyridyl)-1,2, 4-triazole) (4), the density functional theory (DFT) method at the B3.YP level was used to optimize the geometrical structures in the ground and excited state. The absorption and emission properties of the dichloromethane solution were predicted at the time-dependent density functional theory (TD-DFT, B3.YP) level associated with the PCM solvent effect model, the transitions characters of them were assigned. Important correlations between substituent effects and emission spectra and the quantum yield have been obtained by comparing and analyzing the calculated results.

关键词： pyridyl triazole Os(Ⅱ) complexes excited state density functional theory TD-DFT substituent effects

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 key laboratory of {3. materials,jilin university,changchun 13.012.china 2 College of Physics,jilin university,changchun 13.023.china 3.The ordnance Engineering Department,Air Force Aviation university,changchun 13.022,china 1. state key laboratory 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

A local spin evaluation into the active site models of [2Fe2S] ferrodoxin [Fe_2S_2(SR)_4]^(2-) (R=-H, -CH_3.

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Science china Chemistry 2007年第3期50卷 327-334页

作者： WEI JiChong1,2, WANG Yan3.& JU GuanZhi2,3.1 Department of Chemistry, Hainan Normal university, Haikou 571158, china 2 state {3. laboratory of Theoretical and Computational Chemistry, jilin university, changchun 13.023. china 3.Department of Chemistry, Nanjing university, Nanjing 210093. china 1. Department of Chemistry Hainan Normal University Haikou 571158 China 2. state key laboratory of Theoretical and Computational Chemistry Jilin University Changchun 130023 China 3. Department of Chemistry Nanjing University Nanjing 210093 China

To test the feasibility of local spin theory of Davidson and Clark for ferrodoxin clusters, the models [Fe2S2(SR)4]2- (R=-H, -CH3. are chosen for evaluation. This purpose is realized by calculating the local spin expectation values , , and mA and discussing the connection between these expected values and the Heisenberg spin model (HSM) and the Noodleman broken-symmetry approach. In practical calculation, the spin-unrestricted Hartree-Fock (UHF) and spin-polarized density functional theory (DFT) are used and the calculational qualities of these two methods are also discussed. In addition, the theoretical magnetic coupling constants JAB of these models are calculated by various computational schemes for comparison with both theoretical and experimental results previously reported.

关键词： local spin iron-sulfur protein model density function theory magnetic coupling constant

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, jilin 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

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 materials Science, Heilongjiang university, Harbin 150080, china 2. School of Chemistry and Chemical Engineering, Qiqihar university, Qiqihar 161006, china 3. state key laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, jilin university, changchun 13.023. 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(2df) (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 2A′ 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.

Studies on Determining Method of Trehalose

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Chemical Research in Chinese Universities 2000年第1期16卷 10-14页

作者： LIU Tie-min (state key laboratory of Enzyme Engineering,{3., changchun 13.023. P. R. china) LIU Ying (changchun Institute of Biological products, changchun 13.062, P. R. china) jilin Univ State Key Lab Enzyme Engn Changchun 130023 Peoples R China changchun Inst Biol Prod Changchun 130062 Peoples R China

Trehalose can be determined by thin layer chromatography and high performance liquid chromatography. But it's difficult to distinguish trehalose from the similar bisaccharides. If the reaction of the reduced bisaccharides with phenyl hydrazine to form osazone is used, then the disturbance of the similar reduced bisaccharides can be rapidly and conveniently excluded, or via the ammoniated-reduced reaction, aliline can be specially bounded to the reduced hydroxyl of the bisaccharides. In that way trehalose can be accurately determined.

关键词： Trehalose Thin layer chromatography High performance liquid chromatography Osazone Ammoniated-reduced reaction