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Chinese Journal of Polymer Science 1987年第1期5卷 45-52页

作者：陈滇宝许光唐学明 Qingdao College of Chemical Technology Qingdao

Ni（Ⅱ） naphthenate in hydrogenated gasoline or toluene will appear light green, which is the result of absorption in the red and blue bands of the spectrum. The three peaks caused by the spin-allowed d-d transitions are 403, 680, and 1170nm respectively, and are similar to those of Ni（H2O）6+2. The configuration of Ni（Ⅱ） complex is *** a two-component system of Ni（naph）2-Al（i-Bu）3, the naphthenate ligand attached to Ni（Ⅱ） can be exchanged for the alkyl group on tri-isobutylaluminium, if Al（i-Bu）3/Ni（naph）2 in a system. containing metalalkyl and naphthenate does not exceed the value of 0.53. At a higher ratio, Al（i-Bu）3/Ni（naph）2>0.53, Ni（Ⅱ） is reduced to Ni（Ⅰ） and Ni（O）.In a two-component system Ni（naph）2-BF3·OEt2, a part of the naphthenate can be exchanged for halogen. A new Ni（Ⅱ） complex is formed, which consists of three new d-d bands in the region 360-1660 nm.

关键词： cis-1, 4-polybutadiene Nickel catalyst Ziegler-Natta catalyst uv-vis spectrum

TDDFT Study on the Electronic Excitations and First Hyperpolarizabilities of Mixed-metal Carbonyl Clusters W_2Ir_2(μ-L)(CO)_8(η～5-C_5H_4Me)_2(L=dppe/dppf)

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Chinese Journal of Structural Chemistry 2009年第1期28卷 99-105页

作者：李福君洒荣建吴克琛 State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences

Mixed-metal carbonyl clusters of W2Ir2（CO）10（η^5-C5H4Me）2 1 and W2Ir2（μ-L）（CO）8（η^5-C5H4Me）2 （L = dppe 2, dppf 3） have been studied by TDDFT method focusing on their electronic and nonlinear optical properties. These three clusters exhibit the first static hyperpolarizabilities of medium magnitude （βtot-10×10^-30 esu）. The origin of β is discussed by the new proposed orbital-pair decomposition scheme by Barandes et al. The result suggests that the β values of the two clusters are mainly originated from d-d electron transition within the metal skeleton, and d-p （π＊） electron transition from metals to carbonyls and phenyl. The additional coordination by the electron donor group, ferrocene, makes cluster 3 own much larger β values, and the relatively longer range charge transfer from d orbitals of ferrocene to d orbirals of Ir and W is responsible for the enhanced β values.

关键词： TDDFT uv-vis spectrum transition metal nonlinear optical

Electronic Structure and Physical Characteristics of Dioxin Under External Electric Field

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Computers, Materials & Continua 2018年第4期55卷 165-176页

作者： Wenyi Yin Xiangyun Zhang Bumaliya Abulimiti Yuzhu Liu Yihui Yan Fengbin Zhou Feng Jin Jiangsu Key Laboratory for Optoelectronic Detection of Atmosphere and Ocean Nanjing University of Information Science&TechnologyNanjing 210044P.R.China Jiangsu Collaborative Innovation Center on Atmospheric Environment and Equipment Technology(CICAEET) Nanjing210044P.R.China College of Physics and Electronic Engineering Xinjiang Normal UniversityUrumqi 830054P.R.China Advanced Technology Core Baylor College of MedicineHoustonTX 77030USA

Dioxin is a highly toxic and caustic substance,which widely existed in the atmosphere,soil and water with tiny *** pollution has become a major problem that concerns the survival of mankind,which must be strictly *** bond length,bond angle,energy,dipole moment,orbital energy level distribution of dioxin under the external field are investigated using DFT(density functional theory)on basis set level of B3LYP/6-31G(d,p).The results indicate that with the increase of the electric field,the length of one Carbon-Oxygen bond increases while another Carbon-Oxygen bond *** energy gradually decreases with the electric field,while the change of the dipole moment has an opposite *** the infrared spectra,the vibration frequency decreases with the electric field increasing and shows an obvious red ***,the ultraviolet-visible absorption spectra under different electric fields are analyzed with TD-DFT(time-dependent density functional theory)*** wavelength of the strongest absorption peak increases and occurs red shift with the increase of the electric *** the above results can provide reference for further research on the properties of dioxin under different external electric field.

关键词： Dioxin IR spectrum uv-vis spectrum electric field density functional theory excited states

Synthesis and Spectroscopic Properties of a Series of New tetra-Substituted Metal Phthalocyanines

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Chemical Research in Chinese Universities 2008年第2期24卷 123-128页

作者： YU Hai-ling YANG Jin, FU Qiang MA Ji-cheng LI Wei-li Faculty of Chemistry Northeast Normal University Changehun 130024 P. R. China

A new class of metal phthalocyanines（MPcs） containing four 8-quinolinol（8-QH） derivative moieties were successfully synthesized and characterized by mass spectroscopy, IR, uv-vis and element analysis, the results of which were consistent with the proposed structures. All of them can dissolve in common organic solvents, such as dichloromethane, chloroform, and acetone. The effect of metal ion on the absorption of Q band was studied with uv-vis spectra. The fluorescent properties for those complexes were also investigated.

关键词： Metal phthalocyanines Soluble 8-Quinolinol uv-vis spectrum

Electronic and Spectroscopic Properties of La2@C112 Isomers

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Chemical Research in Chinese Universities 2018年第2期34卷 241-246页

作者： WANG Mingqian WANG Boning LI Weiqi ZHOU Xin YANG Li TIAN Weiquan Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage Ministry of Industry and Information School of Chemistry and Chemical Engineering Harbin Institute of Technology Harbin 150080 P. R. China Department of Physics Harbin Institute of Technology Harbin 150001 P. R. China College of Chemistry and Chemical Engineering Chongqing University Chongqing 401331 P. R. China

Among the 3352 isolated pentagon rule（IPR） isomers and 129073 non-IPR isomers satisfying adjacent pentagon pairs（APPs）≤2 of fullerene C112, the lowest-energy IPR and non-IPR isomers of C112 and C112^6- have been fully screened by the density functional tight-binding（DFTB） and density functional theory（DFT） methods for stu- dying the electronic and spectroscopic properties of La2@C112. The structural features and infrared and absorption spectra of those isomers were analyzed in detail, and the characteristic fingerprint absorption peaks were assigned. To clarify the relative stabilities of La2@C112 isomers at high temperature, entropy contributions were determined at the B3LYP level. IPR isomer La2@C112（C2：860136） is not the lowest-energy isomer but is one of the most important isomers. This is the first work that considers non-IPR C112 isomers when exploring the structure and properties of La2@C112.

关键词： C112 fullerene La-endohedral metallofullerene(La-EMF) Thermostability IR spectnan uv-vis spectrum

Structural and optical properties of polycrystalline CdS thin films deposited by electron beam evaporation

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Journal of Semiconductors 2011年第2期32卷 15-18页

作者：杨定宇朱兴华魏昭荣杨维清李乐中杨军高秀英 School of Optoelectronic Technology Chengdu University of Information Technology

Highly crystalline and transparent cadmium sulphide （CdS） films were deposited on glass substrate by electron beam evaporation technique. The structural and optical properties of the films were investigated. The X-ray diffraction analysis revealed that the CdS films have a hexagonal structure and exhibit preferred orientation along the （002） plane. Meanwhile, the crystalline quality of samples increased first and then decreased as the substrate temperature improved, which is attributed to the variation in film thickness. uv-vis spectra of CdS films indicate that the absorption edge becomes steeper and the band gap present fluctuation changes in the range of 2.389-2.448 eV as the substrate temperature increased. The photoluminescence peak of the CdS films was found to be broadened seriously and there only emerges a red emission band at 1.60 eV. The above results were analyzed and discussed.

关键词： polycrystalline CdS thin film substrate temperature uv-vis spectrum photoluminescence spectrum

Ligand-controlled First Hyperpolarizabilities of a Series of Tetrahedral Iridium Clusters Ir_4(CO)_9L: a TDDFT Study

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Chinese Journal of Structural Chemistry 2009年第1期28卷 106-112页

作者：李福君洒荣建吴克琛 State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences

A series of tetrahedral iridium carbonyl clusters coordinated by systematically varied series of ligands have been studied by TDDFT method focusing on their electronic and non- linear optical properties. The clusters of Ir4（CO）12 （1）, Ir4（μ-CO）3（CO）9 （2）, Ir4（μ-L）（CO）10 （L = dppm 3, dppe 4, （Ph2P）2CHMe 5, Ph2P（CH2）3PPh2 6） and Ir4（CO）10（phen）（phen = 1,10-phen- anthroline）（7） exhibit the first static hyperpolarizabilities of medium magnitude （βtot-10×10^-30 esu）. The second order nonlinear optical response of the seven clusters increase from 0 to 23 ×10^-30 esu; the high symmetric cluster Ir4（CO）12 debases its symmetry and presents the second order nonlinear optical behavior as the coordination style of some carbonyls changes to bridge style, and then the response increases regularly with the systematical variation of the ligands. The origination of the first hyperpolarizability is discussed by the expanded orbital decomposition scheme. The results suggest the d-d electron transition from the apical iridium atom to the other three Ir atoms inside the metal skeleton, and d-πelectron transitions from metals to carbonyls are responsible for the first hyperpolarizabilities. Particularly, for cluster 7, the charge transfer from d orbitals of iridium to π＊ orbirals of phenanthroline originates the first hyperpolarizabilities.

关键词： TDDFT uv-vis spectrum iridium duster nonlinear optical

Two Multi-armed Neutral Receptors for α,ω-Dicarboxylate Anions

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Chinese Journal of Chemistry 2006年第4期24卷 527-532页

作者：吴进龙何永炳隗兰华刘顺英徐括喜孟令芝 Department of Chemistry Wuhan University Wuhan Hubei 430072 China

Two new multi-armed neutral receptors 1 and 2 containing thiourea and amide groups were synthesized by simple steps in good yields. Receptors 1 and 2 have a better selectivity and higher association constants for malonate anion than other anions examined by the present work. In particular, distinct color changes were observed upon addition of dicarboxylate anions to the solution of 1 in DMSO. The uv-vis and fluorescence spectra data indicate that a 1 ： 2 stoichiometry complex was formed between compound 1 or 2 and dicarboxylate anions of shorter carbon chain, and a 1 ： 1 stoichiometry complex was formed between compound 1 or 2 and dicarboxylate anions of longer carbon chain through hydrogen bonding interactions.

关键词： neutral receptor anion recognition colorimetric chemosensor dicarboxylate uv-vis spectrum

Synthesis of 5,10,15,20-Tetra[4-（N-ethylpiperazinyl）phenyl]-porphyrin and Its Interaction with DNA

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Chinese Journal of Chemistry 2005年第4期23卷 431-436页

作者：郭灿城李和平张晓兵 CollegeofChemistryandChemicalEngineering HunanUniversityChangshaHunan410082China DepartmentofChemistry ChangshaUniversityofScienceandTechnologyChangshaHunan410077China

Piperazinyl-porphyrin, 5,10,15,20-tetra[4-(N-ethylpiperazinyl)phenyl]porphyrin (TEPPH2), was synthesized based on the special affinity of porphyrin to cancer cells and the antitumor activity of piperazine compounds. Its structure was characterized by uv-vis and 1H NMR spectra and elemental analysis. A model for the interaction between TEPPH2 and calf thymus DNA was built, and the binding mechanism was investigated by uv-vis and fluorescence spectra. The results indicated that TEPPH2 could intercalate into the base pairs of DNA strongly. One calf thymus DNA molecule could bind 88 TEPPH2 molecules, and the binding constant K is 8.4 × 106 L•miol-1. The binding number and binding constant of TEPPH 2 with DNA are higher than those of the known anti-tumor drugs, tetrakis(4-N-methylpyridyi)porphine and the Schiff bases Ca/sal-his and Ni/sal-aln. © 2005 SIOC, CAS, Shanghai, & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

关键词： 5,10,15,20-tetra[4-(N-ethylpiperazinyl)phenyl]porphyrin Calf thymus DNA Fluorescence spectrum Synthesis uv-vis spectrum

Fabrication, Characterization, and Surface-Enhanced Raman Activity Study of Silver Coated Gold Nanoparticulate Films

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Chinese Journal of Chemistry 2007年第5期25卷 609-615页

作者：方靖淮仲崇贵沐仁旺施建珍葛存旺 Department of Physics Nantong University Nantong Jiangsu 226007 China Department of Chemistry Nantong University Nantong Jiangsu 226007 China

This paper reports a study on the preparation of Ag-clad Au colloidal monolayer films by a combination of colloid self-assembly and liquid phase microwave high-pressure technique. Firstly, monodisperse Au nanoparticles prepared by microwave heating method were assembled onto a quartz slide. Then, these Au colloidal particles on the quartz surface acted as seeds for growing the Ag-clad Au composite particulate films. The obtained particulate films were characterized by uv-vis spectra and atomic force microscopy. It was found that the thickness of the shell and thus the size of particles in the composite colloidal films could be controlled by deposition of Ag on the preformed Au colloidal particle film in the microwave reaction system, and such films significantly increased the surface-enhanced Raman scattering enhancement （SERS） ability compared with Au colloidal particle films. Their strong enhancement ability may mainly stem from relatively large particle consisting of Ag cladding as well as effective coupling among particles in the Ag-clad Au particle ftlms.

关键词： assembly microwave heating uv-vis spectrum surface morphology SERS