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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 state key laboratory of {3. 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 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 123.consistent with the electron-donating of H

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

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, Chang{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, Chang{3. 13.023. 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 laboratory of {3. 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

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 {3. laboratory of computational theoretical chemistry,jilin university,Changchun,jilin 13.023 Institute of theoretical chemistry and state {3. 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

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 Department of chemistry Hainan Normal UniversityHaikou 571158China state key laboratory of {3. and computational chemistry Jilin UniversityChangchun 130023China Department of chemistry Nanjing UniversityNanjing 210093China

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

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 School of chemistry and Materials Science Heilongjiang University Harbin China School of chemistry and Chemical Engineering Qiqihar University Qiqihar China jilin university 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.

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 {3. 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

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 {3. 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 China College of chemistry Jilin University Changchun China laboratory of Physical chemistry School of Chemistry and Materials Science Heilongjiang University Harbin 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

DFT evaluation of the electronic structures and spectroscopic properties of the self-assembled [Pt_2M_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 laboratory of {3. and computational chemistry,Institute of {3. chemistry,jilin university,Changchun 13.023.China 2 College of chemistry,jilin university,Changchun 13.023.China state key laboratory of {3. 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 [Pt2M4(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 *** [Pt2Ag4(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 450,3.5 and 3.5 nm and the emissions are at 611,43. and 43. nm for [Pt2Cu4(C≡CH)8],[Pt2Ag4(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 [Pt2M4(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 [Pt2Ag4(C≡CH)8] are augmented,the emissions of [Pt2Ag4(C≡CH)8] clusters bear prominent ILCT character,which is the reason why the emission wavelengths of [Pt2Ag4(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, China 2. state {3. laboratory of theoretical and computational chemistry, Institute of theoretical chemistry, jilin university, Changchun 13.023. China College of chemistry and Chemical Engineering Heilongjiang University Harbin China state key laboratory of {3. 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 B3.YP/6-3.1G(d) and QCISD(t)/6-3.1+G(2df)(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, 2A'), 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(2Π) 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(2Π) + PN(1Σ)→ E1 and the standard enthalpy of formation of isomer E1 are 215.25 and 457.99 kJ/mol, respectively, at 298.15 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.