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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 {2. and {3. chemistry,institute of {2. chemistry,jilin university,changchun 130023,{12. State key laboratory of {2. and {3. 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 12.3.consistent with the electron-donating of H

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

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 {2. 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 {2. 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=91.3.(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.

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 {3. for Supramolecular Structure and Material of Ministry of Education,{2., changchun 13.012. P. R. china 2. Science and Engineering College of chemistry and Biology, Yantai university, Yantai 2.4005, P. R. china 3. State key {3. of theoretical and computational chemistry,{2., changchun 130023, 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 {2. and {3. 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

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 laboratory of {2. and computational chemistry,institute of {2. chemistry,jilin university,changchun 130023,{12. 2.College of chemistry,jilin university,changchun 130023,{12. State key laboratory of {2. and {3. 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 450,3.5 and 3.5 nm and the emissions are at 611,43. and 43. 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

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 {2. of {3. theoretical chemistry,jilin university,changchun,jilin 130023 institute of theoretical {2. and State {3. 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

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,{2. 2. School of chemistry and Chemical Engineering, Qiqihar university, Qiqihar 161006,{2. 3. State key laboratory of theoretical and computational chemistry,{13.,{12., changchun 130023,{2. 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(2.f) (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 2.′ 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 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 {2. and computational chemistry, institute of theoretical chemistry, jilin university, changchun 130023, china 2.College of chemistry, jilin university, changchun 130023, china 3.laboratory of Physical chemistry, School of chemistry and Materials Science, Heilongjiang university, Harbin 150080, china State key laboratory of {2. and {3. 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/LANL2.Z and CIS/LANL2.Z 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 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.State {2. laboratory of theoretical and computational chemistry institute of theoretical chemistry,jilin university,{12. 130023,china College of Chemical and Environmental Engineering Harbin University of Science and Technology Harbin China State key laboratory of {2. and {3. 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

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 {2. {3. university changchun 130023 PRC institute of theoretical {2. 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.