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Bonding Energy of a Molecular Orbital(Ⅱ)——Ab initio Calculation

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Chemical Research in Chinese Universities 1992年第2期8卷 96-98页

作者： YANG zhong-zhi and shen er-zhong (institute of theoretical chemistry, jilin university, changchun, 130023)

Calculation of the bonding energy of a molecular orbital for a series of small molecules has been carried out by using ab initio STO-3G method. The results obtained demonstrate that the concept of the molecular orbital bonding energy is applicable for judging whether a molecular orbital is bonding, nonbonding or antibonding besides Mulliken overlap criterion.

关键词： Molecular orbital Bonding energy,Ab initio STO-3G

ON THE OVerLAPPING ATOMIC-SPHerE MSW-X_α THEORY

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Science China chemistry 1990年第4期33卷 400-408页

作者：王义孙家钟institute of theoretical chemistry jilin university changchun 130023 PRC institute of theoretical chemistry Jilin University Changchun 130023 PRC

By means of four different kinds of two-center expansions of the free-space Green function, the generalized scattered-wave molecular-orbital theory proposed by Johnson is resolved to approach the overlapping atomic-sphere MSW-X_α method. The improved result for the overlapping atomic-sphere is obtained to keep the computational advantages of the well-known nonoverlapping atomlc-sphere model without involving multicenter molecular integrals.

关键词： overlapping sphere X_0 Green function nonlocal potential.

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, jilin university, changchun 130023, China institute of theoretical chemistry, jilin university, changchun 130023, China College of chemistry and State Key Laboratory of Inorganic Synthesis and Preparative chemistry Jilin University Changchun China institute of theoretical chemistry Jilin University 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=91.37(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.

Au-chin Tang——A prestigious scientist,outstanding educator and distinguished leader

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Science China chemistry 2008年第12期51卷 1142-1145页

作者： institute of theoretical chemistry, jilin university, changchun 130023 Prof. Zhang Hongxing institute of theoretical chemistry Jilin University

Au-chin Tang (1915-2008), member of the Chinese Academy of Sciences (CAS), was born in Yixing, Jiangsu Province on November 18th, 1915. During his lifetime, he held various positions such as president

关键词： Au-chin Tang A prestigious scientist,outstanding educator and distinguished leader

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 Laboratory of Computational theoretical chemistry,jilin university,changchun,jilin 130023 institute of theoretical chemistry and State 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 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, jilin university, changchun 130023, China State Key Laboratory of theoretical and Computational chemistry Institute of Theoretical Chemistry Jilin University Changchun 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 B3LYP 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, B3LYP) 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

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 theoretical and Computational chemistry,institute of theoretical chemistry,jilin university,changchun 130023,China State Key Laboratory 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 1<2<3,consistent with the electron-donating of H

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

Studies on the Interaction of 12-Tungstophosphoric Acid and Diethylene Glycol

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Chemical Research in Chinese Universities 1993年第4期9卷 317-323页

作者： ZHAO Yu-sheng, HUA Shi-ying , WU Tong-hao and WEI Quan (Department of chemistry, jilin university, changchun, 130023) Worked in institute of theoretical chemistry, jilin university, changchun.

The homogeneous system of 12-tungstophosphoric acid and diethylene glycol was studied using IR and NMR spectra. It was found that the protons in 12-tungstophosphoric acid formed proton oxonium ions with the hydroxyl oxygen in diethylene glycol by hydrogen-bonds, and the formed proton oxonium ions could react with the terminal oxygens of heteropoly anions. The dehydration-cyclization mechanism of diethylene glycol in the presence of heteropoly acid was also proposed.

关键词： IR NMR Diethylene glycol Proton oxonium ions

Effect of Substituting Group on the Calculated Nonlinear Second－Order Optical Susceptibilities of Substituted Thiophene Derivatives with Quinoidlike Conformation

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Chemical Research in Chinese Universities 1995年第4期11卷 336-341页

作者： LI Zhi-ru WANG Xiao-peng PENG Ji-kang andSUN Chia-chun(Department of chemistry and institute of theoretical chemistry,jilin university,changchun,130023) jilin UNIV DEPT CHEMCHANGCHUN 130023PEOPLES R CHINA jilin UNIV INST THEORET CHEMCHANGCHUN 130023PEOPLES R CHINA

alculations of the nonlinear second-order optical susceptlbilities(β_(ijk))for sub- stituted tl1iophene derivative;with quinoidlike conformation are *** systetems possess small dipole moment;and large differences between dipole mo- ments of ground and first-excited *** optimizations of the molecules investigated were carried out using AM 1 *** calculations were performed using INDO/CI method comboned with a sum-over-states expression for β_(jik). The calculated results sbw that the second-order susceptibility is a function of the na- ture and location of substituents and is larger for disubstituted molecules than monosubstituted molecules. Bipolymeric thiophenemetmne with NH_2/NO_2 groups was calctilated to have a β_μof 79. 920 × 10￣(-30) esu. It was found that the NH_2 and NO_2 groups in above disubstituted molecules are pull-pull groups in ground states,but are usual push-pull groups in the first excited states.

关键词： Nonlinear second-order optical susceptibility INDO/CI,Substituted thiophene derivatives