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Solvent Effect on Characteristic Vibration of ir spectrum of 4,4＇-Dibromodiphenyl Ether

Chemical Research in Chinese Universities 2014年第6期30卷 997-1004页

作者： LI Yu Resources and Environmental Research Academy Key Laboratory of Regional Energy Systems Optimization Ministry of Education North China Electric Power University Beijing 102206 P. R. China

The optimal geometry, ir spectrum and vibration assignment of 4,4＇-dibromodiphenyl ether（BDE-15） in gas phase were calculated via the density functional theory（DFT） at the level of B3LYP/6-3 l＋G（d）. Based on the vi- bration assignment, the calculation of vibration frequencies and intensities of 5 main vibration types of BDE-15 in 25 kinds of solvents was carried out by means of a self-consistent reaction field（SCRF） theoretical model at the level of B3LYP/6-31＋G（d） to analyze the solvent effect on the vibration of ir spectrum of BDE-15. To study the solvent ef- fect further, C--O asymmetric stretching vibration fluctuating, which is relatively acute in both vibration frequency and intensity, was selected as the characteristic vibration to establish different linear solvation energy relation（LSER） models for solvent categoring. Solvent parameters（a, /3, ~r＊）, acceptable number（AN） and quantitative structure- activity relationship（QSAR） models were established via chemical quantum parameters of solvent moleculer, which were first been introduced to investigate different solvent-solute interaction mechanisms in alcoholic and non-alcoholic solvents on molecular level. At last, a single solvent molecule was embedded in the framework of po- larizable continuum model（PCM） to validate the effect of hydrogen bonding on solvent-solute interaction in alcohol solvents. The obtained results show that 5 main vibration types of BDE-15 in different solvents have small variation range in frequency and intensity and all the vibration frequencies in solvents are lower than those in gas phase, de- creasing along with the increasing of the dielectric Constant（e） of solvents exponentially. In contrast, all the vibration intensities in solvents are greater than those in gas phase and present positive exponential trend. Twenty-five solvents were divided into two categories（non-alcoholic solvents and alcoholic solvents） by LSER. The CmO asymmetric stretching vibration was mainly regulated b

关键词： Solvent effect ir spectrum Vibration assignment Quantitative structure-activity relationship Hydrogenbonding

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Conformations and Metal Ion Affinities of Glutamine Binding with Alkali and Alkaline Earth Metal Cations： an ab initio Study

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Chinese Journal of Chemical Physics 2014年第2期27卷 189-199,I0004页

作者：庞瑞带子敬中国科学技术大学物理系苏州纳米科技协同创新中心合肥230026

Conformations and reaction energetics are important for understanding the interactions be- tween biomolecules and metal ions. In this work, we report a systematic ab initio study on the conformations and metal ion affinities of glutamine （Gln） binding with alkali and alkaline earth metal ions. An efficient and reliable method of searching low energy conformations of metalated Gln is proposed and applied to the complexes of ***.M^＋/＋＋（M＋/＋＋=Li^＋、Na^＋、K^＋、Rb^＋、Cs^＋、Be^＋＋、Mg^＋＋、Ca^＋＋、Sr^＋＋ and Ba^＋＋）.. In addition to all conformers known in literatures, many new important conformations are located, demonstrating the power of the new method and the necessity of the conformational search performed here. The metal coordination modes, relative energies, dipole moments, and equilibrium distributions of all important conformations of Gln.M^＋/＋＋ are calculated by the methods of B3LYP, BHandHLYP, and MP2. ir spectra and metalation enthalpies and free energies are also presented and compared with the available experiments. The results form an extensive database for systematic examination of the metalation properties of Gln.

关键词： Conformational search method Complexation structure Conformational distribution ir spectrum Binding energy

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Local Structures and Chemical Properties of Deprotonated Arginine

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Chinese Journal of Chemical Physics 2012年第6期25卷 681-686,I0003,I0004页

作者： Hong-bao Li Zi-jing Lin Yi Luo Hefei National Laboratory for Physical Sciences at the Microscale and Department of Physics University of Science and Technolo&y of China Hefei 230025 China Department of Theoretical Chemistry and Biology School of BiotechnoloEy Royal Institute ofTechnoloEy S-106 91 Stockholm Sweden

The potential energy surface of gaseous deprotonated arginine has been systematically in- vestigated by first principles calculations. At the B3LYP/6-31G（d） level, apart from the identification of several stable local structures, a new global minimum is located which is about 6.56 k J/tool more stable than what has been reported. The deprotonated arginine molecule has two distinct forms with the deprotonation at the carboxylate group （COO-）. These two forms are bridged by a very high energy barrier and possess very different ir spectral profiles. Our calculated proton dissociation energy and gas-phase acidity of argi- nine molecule are found to be in good agreement with the corresponding experimental results. The predicted geometries, dipole moments, rotational constants, vertical ionization energies and ir spectra of low energy conformers will be useful for future experimental measurements.

关键词： Deprotonated arginine Energy barrier ir spectrum Gas-phase acidity

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Extensive Computational Study on Conformations of Microsolvated Leucine Complexes

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Chinese Journal of Chemical Physics 2012年第4期25卷 409-418,I0003页

作者：刘莎胡安东林子敬中国科学技术大学物理系合肥230026

The conformations for leucine （Leu） hydrated with one to three water molecules, Leu-（H2O）n （n=1-3）, were carefully searched by considering the trial structures generated by all possible combinations of rotamers of Leu combined with all likely hydration modes. The structures were optimized at the BHandHLYP/6-31＋G^＊ level and the single point energies were calculated at the BHandHLYP/6-311＋＋G^＊＊ level. Good correspondence between the conformations of Leu-（H2O）n and bare Leu is found, showing that the conformations of Leu-（H2O）n may be efficiently and reliably determined by the hydration of Leu conformers. The simulated ir spectra of canonical and zwitterionic conformers of Leu-（H2O）n are compared with the experimental result of Leu in aqueous solution. The ir spectrum of zwitterionic Leu- （H2O）3 provides the best description of the experiment. The result demonstrates that the ir spectrum of solute in solution may be simulated by the solute hydrated with an adequate number of water molecules in the gas phase.

关键词： Amino acid Hydration effect First principle calculation Potential energy surface ir spectrum

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Theoretical Study of Interaction Between S2 and SiHx （x=1, 2, 3） in Porous Silicon

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Chinese Journal of Chemical Physics 2010年第3期23卷 281-286,I0001页

作者：李佐程新路王江陈海花四川大学原子与分子物理研究所成都610065

The interaction between S2 molecule and SiHx （x=1, 2, 3） in porous silicon is investigated using the B3LYP method of density functional theory with the lanl2dz basis set. The model of porous silicon doped with CH3, Si-O-Si and OH species is built. By analyzing the binding energy and electronic transfer, we conclude that the interaction of S2 molecule with SiHx （x=1, 2, 3） is much stronger than the interaction of S2 molecule with CH3 and OH, as S2 molecule is located in different sites of the model. Using the transition state theory, we study the Si2H6＋S2→H3SiH2SiS＋HS reaction, and the reaction energy barrier is 50.2 kJ/mol, which indicates that the reaction is easy to occur.

关键词： Porous silicon ir spectrum Binding energy Transition state

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Investigation of Syntheses and Spectra (UV,ir,CV) of Some Fe3S3 Cluster Compounds

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Chinese Journal of Structural Chemistry 2000年第2期19卷 131-138页

作者： LIU Ping ② WANG Jian ZHENG Yu (Fujian Institute of Research on the Structure of Matter, the Chinese Academy of Sciences, Fuzhou 350002, China) (E-mail:pliu@***) 中科院福建物质结构所福建福州 3 50 0 0 2

Two new Fe 3S 3 cluster compounds, compound 5 〔Et 4N〕 3〔Fe 3( p ClPhS) 3Cl 6〕 and compound 6 〔Et 4N〕 3〔Fe 3(Cl 5PhS) 3Cl 6〕 have been successfully synthesized with one step reaction. Combination of compounds 5,6 and compounds 1~4 which were synthesized earlier, their UV,ir and CV spectra have been studied systematically, deeply to understand molecular electronic characteristics. There is a blueshift within 260nm and a redshift over 260nm in the UV spectra of compounds, it has been shown that Fe-S cluster needs more energy in transition of electric charge (CT), but needs less energy in d d transition area. In the ir spectra, the most interesting bands appearing in the regions of 422~386cm -1 and 492~474cm -1 are attributed to S-Fe-S (Fe 3S 3 unit) and FeS (Ph-S) stretching vibration respectively. The bands in the region 330~285cm -1 and 245~183cm -1 can be assigned to Fe-Cl and Fe-Br stretching vibration respectively. Their CV spectra show that this is a quasi reversible redox process. In this process, an Fe 2+ loses an electron and is oxidized to Fe 3+ , then gets an electron and is reduced to Fe 2+ . The redox electrical potentials of compounds 1, 3~6 are +0.07V / -0.60V, +0.24V / -0.80V, +0.40V / -0.80V, +0.43V / -1 20V, +0.54V/-1.00V, respectively.

关键词： Fe 3S 3 cluster synthesis UV spectrum ir spectrum CV spectrum

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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

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Solid State Synthesis and Structural Characterization of Binuclear Cu(I) SbPh 3 Complex 〔Cu(SbPh 3) 2I〕 2

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Chinese Journal of Structural Chemistry 1999年第5期18卷 356-360页

作者：张千峰黄永德等 StateKeyLaboratoryofCoordinationChemistry Coordina StateKeyLaboratoryofCoordinat

Dimeric complex 〔Cu(SbPh 3) 2I〕 2 has been synthesized by a solid state reaction at a low heating temperature and its crystal structure has been analyzed by X ray crystallography. The crystal is monoclinic, space group P2 1/a (#14), a = 20 436(5), b=14.125(3), c=24.683(3) , β=110.67(1)°, Z=4, V =6666(2)  3; C 72 H 60 Sb 4I 2Cu 2, M r = 1792, D c = 1.787 g·cm -3 , μ (Mo Kα ) = 31.88 cm -1 , F(000)=3440, R= 0.038 and R w= 0.043 for 5632 observed reflections ( I≥3.0σ(I) ) and 361 refined parameters. The result reveals the copper and the bridging iodide atoms form an approximately planar rhomboid array. Effects of the bulkiness of the ligands upon the structures of the analogous complexes are discussed.\;

关键词： solid state synthesis crystal structure Cu(I) SbPh 3 complex ir spectrum

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An MP2 study on pre-reactive complexes (CH_2)_2O … XY (X,Y = H,F,Cl,Br,I)

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Chinese Journal of Chemistry 1999年第6期17卷 579-585,3页

作者：林晨升刘春万 Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences State Key Laboratory of Structural Chemistry Fuzhou Fujian 350002 China

The structures, energies, atomic chaiges and ir spectra of complexes (CH2)2O…XY (X, Y = H, F, Cl, Br, and I) have been examined by means of ab initio molecular orbital theory at the second-order level of Moller-Plesset perturbation correction. It is found that the hydrogen bond O…H-X is non-linear. The attraction between X and the H atoms in oxirane ring causes O…H-X bond bending. The hydrogen bond slighdy weakens the bond strength of C-O, and leads the bending and stretching mode of ir to shift to the red. The calculation results show that there is no evidence of a significant extent of proton transfer to give (CH2)2OH+ …X- in the isolated complexes.

关键词： Oxirane non-linear hydrogen-bond ir spectrum MP2 method

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UV and ir Studies on Heterofullerene C76BN

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Chinese Journal of Chemical Physics 2006年第4期19卷 301-304页

作者： Shi Wu Qi-wen Teng Department of Chemistry Zhejiang University Hangzhou 310027 China

Twenty-tow possible isomers for C76BN were studied by INDO methods. The two most stable geometries are 52,53-C76BN and 29,28-C76BN, in which boron and nitrogen atoms are connected with each other and located at the 6/6 bond near the longest axis of C78（C2v）. Electronic spectra of C76BN were investigated with INDO/SCI method. UV absorptions of C76BN are red-shifted compared with those of Crs（C2v）. The structures and ir spectra for the four stable isomers of C76BN were calculated by AM1 method. It was indicated that the substitution of the BN unit weakens the conjugation of carbon atoms, leading to the decrease of ir frequencies.

关键词： Heterofullerene C76BN Electronic spectrum ir spectrum

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