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theoretical study of the electronic structures and spectroscopic properties of [(4'-XC≡Ctrpy)PtCl]^+ (trpy=2,2':6',2"-terpyridine;X=H,Me and Ph)

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Science china chemistry 2009年第12期52卷 2226-2236页

作者： WANG Xin,BAI FuQuan,ZHOU Xin,LIU Tao & ZHANG HongXing state key laboratory of {3. and computational chemistry,institute of {3. chemistry,jilin university,Changchun 13.023.china 1. state key laboratory of {3. and computational chemistry Institute of Theoretical Chemistry Jilin University Changchun 130023 China

The electronic structures and spectroscopic properties of [(4'-XC≡Ctrpy)PtCl]+(trpy = 2,2':6',2″-terpyridine; X = H (1),methyl (Me) (2),and phenyl (Ph) (3. were studied by the ab initio method. The structures at the ground and excited state were optimized at the B3.YP and CIS levels,respectively. The absorption and emission spectra in the dichloromethane solution were obtained by using the TD-DFT (B3.YP) method associated with the PCM model. The molecular orbital energy of the HOMOs of 1-3.with the d(Pt),p(Cl),π(trpy),and π(XC≡C) character is sensitive to the substituents on the acetylide ligand,but that of the trpy-based LUMOs with the π*(trpy) character varies slightly. The lowest lying emission at 503.nm for 1 is mainly attributed to the 3.LCT perturbed by the 3.LCT and 3.LCT transitions,but that at 53. nm for 2,and that at 558 nm for 3.are mainly attributed to the 3.LCT perturbed by the 3.LCT and 3.LCT transitions. The different electron-donating ability of H,Me,and Ph is responsible for the differences in emission character. Moreover,the calculation results show that the phosphorescent color can be turned by adjusting the substituents. Both the lowest energy absorption and emission of 1―3.are red-shifted in the order of 13.consistent with the electron-donating of H

关键词： platinum(Ⅱ) complexes TD-DFT absorption spectra charge transfer luminescence

Electronic structure and photoelectron spectrum Assignment of allene

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Chinese Journal of chemistry 1993年第5期11卷 406-411页

作者： WANG,Zhi-Zhong YANG,Ming YANG,Zhong-Zhi institute of theoretical chemistry and state key {3. of computational theoretical chemistry,jilin university,Changchun,jilin 13.023 institute of theoretical chemistry and {3. key laboratory of computational theoretical chemistry Jilin University Changchun Jilin 130023

In this paper a series of ab initio SCF and configuration calculations were reported for the ground state and excited states X^2E, A^2E,~2B_2 and ~2A_1 of *** ground state X^2E Jahn- Teller distorsion was discussed and a twisted angle of 50° and a torsional barriers of 0.21—0.51 eV were *** on calculated results,the experimental photoelectron spectrum of allene has been assigned.

关键词： SCF Electronic structure and photoelectron spectrum Assignment of allene Cl

theoretical Study of CH_3.H=CH_2+O(~1D) Reaction: Mechanism and Kinetics

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Chemical Research in Chinese Universities 2012年第1期28卷 147-152页

作者： WU Nan-nan, LIU Hong-xia, DUAN Xue-mei and LIU Jing-yao state key laboratory of {3. and computational chemistry, institute of theoretical chemistry, jilin university, Changchun 13.021, P. R. china institute of theoretical chemistry Jilin University State Key Laboratory of Theoretical and Computational Chemistry Changchun 130021

The mechanism and kinetics for the reaction of propene（CH3.H=CH2） molecule with O（1D） atom were investigated theoretically. The electronic structure information of the potential energy surface（PES） was obtained at the B3.YP/6-3.1＋G（d,p） level, and the single-point energies were refined by the multi-level MCG3.MPWB method. The calculated results show that O（1D） atom can attack CH3.H=CH2 via the barrierless insertion mechanism to form four energy-riched intermediates CH3.（OH）CH2（IM1）, CH3.HCHOH（IM2）, CH2OHCHCH2（IM3. and cyclo CH2OCHCH3.IM4）, respectively, on the singlet PES. The branching ratios as well as the pressure and temperature dependence of various product channels for this multi-well reaction were predicted by variational transition-state and Rice-Ramsperger-Kassel-Marcus（RRKM） theories. The present results will be useful to gain a deep insight into the reaction mechanism and kinetics of CH3.H=CH2＋O（1D） reaction.

关键词： Propene O(lD) Mechanism Kinetics

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 {3. of Inorganic Synthesis and Preparative chemistry, jilin university, Changchun 13.023. china institute of theoretical chemistry, jilin university, Changchun 13.023. china 1. College of chemistry and state key {3. 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.

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 {3. 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.

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 {3. key 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 {3. 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

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, Changchun {3.012, 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, Changchun 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

Molecular Docking of 3.Methylindole-containing Drugs Binding into CYP3.4

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Chemical Research in Chinese Universities 2012年第1期28卷 137-141页

作者： MENG Xuan-yu, LI Zhuo, NIU Rui-juan, ZHANG Hong-xing and ZHENG Qing-chuan state key laboratory of {3. and computational chemistry, institute of theoretical chemistry, jilin university, Changchun 13.021, P. R. china jilin Univ Inst Theoret Chem State Key Lab Theoret & Computat Chem Changchun 130021 Peoples R China

Drugs SPD-3.4（6,7-dimethyl-3.{[methyl-（2-{methyl-[1-（3.trifluoromethyl-phenyl）-1H-indol-3.ylme thyl]-amino}-ethyl）-amino]-methyl}-chromen-4-one） and zafirlukast contain a common structural element of 3.substituted indole moiety which closely relates to a dehydrogenated reaction catalyzed by cytochrome P450s（CYPs）. It was reported that the dehydrogenation can produce a reactive electrophilic intermediate which cause toxicities and inactivate CYPs. Drug L-745,870（3.{[4-（4-chlorophenyl）piperazin-1-yl]-methyl}-1H-pyrrolo 2,3.β-pyridine） might have similar effect since it contains the same structural element. We used molecular docking approach combined with molecular dynamics（MD） simulation to model three-dimensional（3.） complex structures of SPD-3.4, zafirlukast and L-745,870 into CYP3.4, respectively. The results show that these three drugs can stably bind into the active site and the 3.methylene carbons of the drugs keep a reasonable reactive distance from the heme iron. The complex structure of SPD-3.4-CYP3.4 is in agreement with experimental data. For zafirlukast, the calcu lation results indicate that 3.methylene carbon might be the dehydrogenation reaction site. Docking model of L-745,870-CYP3.4 shows a potential possibility of L-745,870 dehydrogenated by CYP3.4 at 3.methylene carbon which is in agreement with experiment in vivo. In addition, residues in the phenylalanine cluster as well as S119 and R212 play a critical role in the ligands binding based on our calculations. The docking models could provide some clues to understand the metabolic mechanism of the drugs by CYP3.4.

关键词： CYP3.4 Molecular docking Molecular dynamics(MD) simulation

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 {3. and computational chemistry, institute of theoretical chemistry, jilin university, Changchun 13.023. china 2 College of chemistry, jilin university, Changchun 13.023. china 3.laboratory of Physical chemistry, School of chemistry and Materials Science, Heilongjiang university, Harbin 150080, china state key laboratory of {3. 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