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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

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 theoretical and Computational chemistry,institute of theoretical chemistry,jilin university,changchun 130023,china 2 College of chemistry,jilin university,changchun 130023,china State Key Laboratory 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 [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 450,365 and 375 nm and the emissions are at 611,431 and 435 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

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

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

Decoding the inconsistency of six cropland maps in china

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The Crop Journal 2024年第1期12卷 281-294页

作者： Yifeng Cui Ronggao Liu zhichao Li Chao zhang Xiao-Peng Song jilin Yang Le Yu Mengxi Chen Jinwei Dong institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China university of Chinese Academy of Sciences Beijing 100049China department of Geographical Sciences University of MarylandCollege ParkMD 20740USA College of Grassland Science and Technology China Agricultural UniversityBeijing 100193China Ministry of Education Ecological Field Station for East Asian Migratory Birds Department of Earth System ScienceInstitute for Global Change StudiesTsinghua UniversityBeijing 100084China Ministry of Education Ecological Field Station for East Asian Migratory Birds Beijing 100084China Tsinghua university(department of Earth System Science)-Xi’an institute of Surveying and Mapping Joint Research Center for Next-Generation Smart Mapping Beijing 100084China institute of Remote Sensing and Geographic Information System Peking UniversityBeijing 100871China department of Forest and Conservation Sciences University of British ColumbiaVancouverBCV6T 1Z4Canada

Accurate cropland information is critical for agricultural planning and production,especially in foodstressed countries like *** widely used medium-to-high-resolution satellite-based cropland maps have been developed from various remotely sensed data sources over the past few decades,considerable discrepancies exist among these products both in total area and in spatial distribution of croplands,impeding further applications of these *** factors influencing their inconsistency are also *** this study,we evaluated the consistency and accuracy of six cropland maps widely used in china in circa 2020,including three state-of-the-art 10-m products(i.e.,Google Dynamic World,ESRI Land Cover,and ESA WorldCover)and three 30-m ones(i.e.,GLC_FCS30,GlobeLand 30,and CLCD).We also investigated the effects of landscape fragmentation,climate,and agricultural *** using a ground-truth sample revealed that the 10-m-resolution WorldCover provided the highest accuracy(92.3%).These maps collectively overestimated Chinese cropland area by up to 56%.Up to 37%of the land showed spatial inconsistency among the maps,concentrated mainly in mountainous regions and attributed to the varying accuracy of cropland maps,cropland fragmentation and management practices such as *** work shed light on the promotion of future cropland mapping efforts,especially in highly inconsistent regions.

关键词： Consistency and accuracy 10-and 30 m Cropland mapping Agricultural management china

FLUORESCENCE　STUDIES　ON　SELF－ASSEMBLING　BEHAVIOR　OF　AMPHIPHILES　WITH　NAPHALENE－1，5－DIOXY　GROUP

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Chinese Chemical Letters 1996年第8期7卷 735-736页

作者： Guo Wen LI Ying Qiu LIANG2(institute of theoretical chemistry, jilin university, changchun, 130023)(department of chemistry, Nanjing university, Nanjing 210093) institute of theoretical chemistry Jilin University Changchun 130023 department of chemistry Nanjing University Nanjing 210093

Fluorescene Spectra in dilute aqueous solution of a series of single chain amphiphileswith an interposed naphthalene-1,5-dioxy group were studied to elucidate the characteristic selfassembling behavior. which indicate... 详细信息

关键词： STABLE BILAYER ASSEMBLIES SINGLE-CHAIN AMPHIPHILES DILUTE AQUEOUS-SOLUTION

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 theoretical 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 theoretical 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 B3LYP/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 CH3CN 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 387 and 391 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 436 and 438 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 (CH3CN) 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

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