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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 {2. of theoretical and computational chemistry,institute of theoretical chemistry,jilin university,changchun {12.,china state key {2. of theoretical and computational chemistry Institute of Theoretical Chemistry Jilin University Changchun 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 B3LYP and CIS levels,respectively. The absorption and emission spectra in the dichloromethane solution were obtained by using the TD-DFT (B3LYP) 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 3ILCT perturbed by the 3MLCT and 3LLCT transitions,but that at 535 nm for 2.and that at 558 nm for 3 are mainly attributed to the 3LLCT perturbed by the 3ILCT and 3MLCT 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 12.3,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 {2. laboratory of computational theoretical chemistry,jilin university,changchun,jilin 13002. institute of theoretical {2. and state key laboratory of computational theoretical {2. 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^2., A^2.,~2._2.and ~2._1 of *** ground state X^2. Jahn- Teller distorsion was discussed and a twisted angle of 50° and a torsional barriers of 0.2.—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

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 {2. laboratory of Inorganic Synthesis and Preparative chemistry, jilin university, changchun 13002., china institute of theoretical chemistry, jilin university, changchun 13002., china College of chemistry and state {2. laboratory of Inorganic Synthesis and Preparative chemistry Jilin University Changchun China institute of theoretical {2. Jilin University Changchun China

A new 2. (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 H2. as raw materials. The crystals of the compound belong to monoclinic P2./n space group, a = 1.012.(2. nm, b = 0.92.5(2. nm, c = 1.5696(3) nm, β=91.37(3)°V=1.472.(5) nm3,Z=3, final R1=0.02.2. wR 2.0.0798 for 2.72.[/>2.(/)] 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 2. 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： 2. coordination polymer, 1,2.4,5-benzentetracarboxylic acid, iron, hydrothermal synthesis, crystal structure.

theoretical Study of CH_3CH=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 {2. of theoretical and computational chemistry, institute of theoretical chemistry, jilin university, changchun 13002., P. R. china institute of theoretical {2. Jilin University State Key Laboratory of Theoretical and Computational Chemistry Changchun 130021

The mechanism and kinetics for the reaction of propene（CH3CH=CH2. molecule with O（1D） atom were investigated theoretically. The electronic structure information of the potential energy surface（PES） was obtained at the B3LYP/6-311＋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 CH3CH=CH2.via the barrierless insertion mechanism to form four energy-riched intermediates CH3C（OH）CH2.IM1）, CH3CHCHOH（IM2., CH2.HCHCH2.IM3） and cyclo CH2.CHCH3（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 CH3CH=CH2.O（1D） reaction.

关键词： Propene O(lD) Mechanism Kinetics

DFT evaluation of the electronic structures and spectroscopic properties of the self-assembled [Pt_2._4(C≡CH)_8](M=Cu,Ag) clusters

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Science china chemistry 2009年第11期52卷 1954-1960页

作者： BAI FuQuan1,XIA BaoHui1,2.ZHANG HongXing1,YANG BaoZhu1,WANG Jian1 & SUN Lei1 1 state key {2. of theoretical and computational chemistry,institute of theoretical chemistry,jilin university,changchun {12.,china 2.College of chemistry,jilin university,changchun {12.,china state key {2. of theoretical and computational chemistry Institute of Theoretical Chemistry Jilin University Changchun China College of chemistry Jilin University Changchun China

Electronic structures and spectroscopic properties of self-assembled [Pt2.4(C≡CH)8](M=Cu,Ag) clusters have been studied by the TD-DFT(time-dependent density functional theory) calculations with the polarizable continuum model(PCM).The ground-and excited-state structures were optimized by the DFT(density functional theory) *** calculated structures and spectroscopic properties are in agreement with the corresponding experimental *** [Pt2.g4(C≡CH)8] clusters have two stable ground state geometries(D4 and D4h symmetry).The calculated Pt-M distances suggest only very weak *** Cu-Cu distances are larger than the van der Waals radii of two Cu atoms and the Ag-Ag distances are analogous with the sum of van der Waals radii of two Ag *** excitation,the interaction of Pt…M,Ag…Ag is strengthened,while the Cu…Cu distances are shortened but they are still larger than the sum of van der Waals radii of two Cu *** lowest-energy absorptions are at 450,365 and 375 nm and the emissions are at 611,431 and 435 nm for [Pt2.u4(C≡CH)8],[Pt2.g4(C≡CH)8](A) and(B),*** transitions are all perturbed by the Cu or Ag composition through the UV-Vis spectra region;therefore,there are not pure ILCT or MPtLCT characteristics(ILCT:intraligand charge transfer;MLCT:metal-to-ligand charge transfer) in absorptions of heteropolynuclear [Pt2.4(C≡CH)8] *** the emissions and the lowest-absorptions have different transition characteristics for each complex,the emissions should not come from the lowest-energy *** the M…M interactions in the excited state of [Pt2.g4(C≡CH)8] are augmented,the emissions of [Pt2.g4(C≡CH)8] clusters bear prominent ILCT character,which is the reason why the emission wavelengths of [Pt2.g4(C≡CH)8] have a small hypsochromic shift relative to the emission wavelength of homoleptic [Pt(C≡CH)4]2.precursor.

关键词： electronic structures luminescence behavior heteropolynuclear complexes TDDFT

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

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Science china chemistry 2004年第2期47卷 98-105页

作者： KAN Wei1, YU Haitao1, LI Mingxia1, FU Honggang1,2.& SUN Jiazhong1,2.1. College of chemistry and Chemical Engineering, Heilongjiang university, Harbin 150080,{2. 2. state key laboratory of theoretical and computational chemistry, institute of theoretical chemistry, jilin university, changchun 13002.,{2. College of chemistry and Chemical Engineering Heilongjiang University Harbin China state key {2. of theoretical and computational chemistry Institute of Theoretical Chemistry Jilin University Changchun China

Some stationary points on the potential energy surface of [Si, N, N, P] system were located at the B3LYP/6-311G(d) and QCISD(t)/6-311+G(2.f)(single-point) levels of theory, while the isomerization, structures, and stability of these obtained isomers were suggested. The computed results indicate that only four-membered ring isomer SiNPN(E1, 2.'), which possesses butterfly-like structure and Si-P cross bonding, is kinetically stable in all optimized isomers. Other isomers may be considered as kinetically unstable towards isomerization or dissociation because of the corresponding smaller reaction barriers. Furthermore, the present paper also proposes electronic and geometric structures, vibrational frequencies and the corresponding vibrational modes, dipole moments, and rotational constants of isomer E1. To make use of the computed results, we can clearly know that the reaction pathway via an intermediate E3 (SiNPN) is the most favorable channel producing isomer E1 from fragments SiN(2.) and PN (1Σ), which have been well characterized in space, and thus, isomer E1 can be considered as a candidate for interstellar observation. The reaction enthalpy of SiN(2.) + PN(1Σ)→ E1 and the standard enthalpy of formation of isomer E1 are 2.5.2. and 457.99 kJ/mol, respectively, at 2.8.15 K. keywords potential energy surface - [Si,N,N,P] system - isomerization - kinetic stability

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

theoretical studies of the transport property of oligosilane

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Science china chemistry 2010年第12期53卷 2571-2580页

作者： ZHANG GuiLing 1,YUAN HongLiang 1,ZHANG Hui 1,SHANG Yan 1,SUN Miao 1,LIU Bo 1 & LI ZeSheng 2.1 College of Chemical and Environmental Engineering,Harbin university of Science and Technology,Harbin 150080,china 2.{2. key laboratory of theoretical and computational chemistry institute of theoretical chemistry,jilin university,changchun 13002.,china College of Chemical and Environmental Engineering Harbin University of Science and Technology Harbin China state key {2. of theoretical and computational chemistry institute of theoretical {2. Jilin University Changchun China

The transport mechanisms of four-conjugated systems were comparatively studied by combining ATK and Gaussian 03 *** was found that the charge-doped oligosilane behaved in a different way from the boron doped and phosphorus doped oligosilanes in terms of the transmission *** charge-doped oligosilane showed almost no conductivity owing to the damage of the electron transfer path by *** contrast,the boron doped and phosphorus doped oligosilanes were demonstrated to be good semiconductors and NDR behavior was observed for *** is a reasonable result after the analysis of the transmission spectra,MPSH states,energy gap,conjugation effect,and scattering effect.

关键词： theoretical study transport property oligosilane

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,{2., changchun 130012. P. R. china 2. Science and Engineering College of chemistry and Biology, Yantai university, Yantai 2.4005, P. R. china 3. state key laboratory of theoretical and {12. chemistry,{2., changchun 13002., P. R. china key laboratory for Supramolecular Structure and Material of Ministry of Education Jiln University Changchun 130012 P. R. China Science and Engineering College of chemistry and Biology Yantai University Yantai 264005 P. R. China state key {2. 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. B3LYP method with the 6-311++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

A local spin evaluation into the active site models of [2.e2.] ferrodoxin [Fe_2._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,{2. 2.state key laboratory of theoretical and computational chemistry, jilin university, changchun 13002.,{2. 3 Department of chemistry, Nanjing university, Nanjing 2.0093,{2. Department of chemistry Hainan Normal University Haikou China state key {2. of theoretical and computational chemistry Jilin University Changchun China Department of chemistry Nanjing University Nanjing China

To test the feasibility of local spin theory of Davidson and Clark for ferrodoxin clusters, the models [Fe2.2.SR)4]2. (R=-H, -CH3) are chosen for evaluation. This purpose is realized by calculating the local spin expectation values , 2.>, 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