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Bonding Energies and Structural Study of Alkylaluminium

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Chinese Journal of Structural Chemistry 2010年第6期29卷 833-838页

作者： ZHAO Yan-Yun CHENG Xue-Li LI Li-Qing LI Zhen Department of Chemistry and Environmental Sciences Taishan University

Neutral aluminium alkyls are well known to act as ethylene oligomerization and polymerization catalysts and *** the basis of the full optimization of alkylaluminium compounds with Gaussian 98 program package at the B3LYP/6-31G＊＊ level,the selected structures and bonding energies were investigated *** geometries and bonding energies of AlR3（R = H,CH3,C2H5,C3H7,C4H9） and Al（C2H5）2R＇（R＇ = C2H5,C3H7,C4H9,C5H11,C6H13） were investigated extensively,and we found that,along with the prolongation of carbon chains the terminal C-C bond is shortened gradually until to a constant value of about 0.1532 nm in C4H9;and the bonding energy almost remains *** dative bonding of C2H4 to Al（C2H5）3,whose bonding energy is only 15.30 kJ/mol,is very weak.

关键词： alkylaluminium bonding energy molecular geometry steric effect

Geometric structure of N_(2)O^(q+)(q=5,6)studied by Ne^(8+)ion-induced Coulomb explosion imaging

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Chinese Physics B 2021年第11期30卷 309-317页

作者： Xi Zhao Xu Shan Xiaolong Zhu Lei Chen Zhenjie Shen Wentian Feng Dalong Guo Dongmei Zhao Ruitian Zhang Yong Gao Zhongkui Huang Shaofeng Zhang Xinwen Ma Xiangjun Chen Hefei National Laboratory for Physical Sciences at the Microscale and Department of Modern Physics University of Science and Technology of ChinaHefei 230026China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China

We report the study on the complete three-body Coulomb explosion(CE)of N_(2)O^(q+)(q=5,6)induced by 56-keV/u Ne8+ion collision with N2O gaseous *** CE channels for N_(2)O^(5+)and seven for N_(2)O^(6+)are identified by measuring three ionic fragments and the charge-changed projectile in quadruple *** the kinetic energy release(KER)and momentum correlation angle(MCA)distributions of three ionic fragments for each of the CE channels are also *** computation is presented to reconstruct the geometric structure of N_(2)O^(q+0prior to dissociation based on the measured KER and *** N–N and N–O bond lengths and the N–N–O bond angles of N_(2)O^(q+)for each of the channels are determined.

关键词： Coulomb explosion kinetic energy release molecular geometry ion collision nitrous oxide(N_(2)O)

Structural and spectroscopic properties of small Pu_n(n=2-5) molecules

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Chinese Physics B 2011年第11期20卷 215-221页

作者：贾婷婷高涛张云光雷强华罗德礼 Institute of Atomic and molecular Physics Sichuan University School of Sciences Xi'an Institute of Posts and Telecommunications National Key Laboratory of Surface Physics and Chemistry

The equilibrium structures and the electronic, spectroscopic and thermodynamic properties of small Pun （n = 2- 5） molecules are systematically investigated using the methods of general gradient approximation （GGA） of density functional theory （DFT）. The results show that the bond length of the lowest-energy structure of Pu2 is 2.578 A. The ground state structure of Pu3 is a triangle with D3h symmetry, whereas for Pu4, the ground state structure is a square （D4h） and the spin polarization of 16 for molecule Pu5 with square geometry （D_4h） is the most stable structure. For the ground state structures, the vibrational spectra as well as thermodynamic parameters are worked out. In addition, the values for the highest occupied molecular orbital （HOMO） and the lowest unoccupied molecular orbital （LUMO） along with the energy gap of all the Pu_2-5 structures are presented. The relevant structural and chemical stabilities are predicted.

关键词： Pu_n molecule molecular geometry vibrational spectrum

Novel Donor-Acceptor Copolymers Based on Dithienosilole and Ketone Modified Thieno[3,4-b]thiophene for Photovoltaic Application

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Chinese Journal of Chemistry 2013年第11期31卷 1455-1462页

作者： Lie Chen Shujiao Cai Xianbo Wang Yiwang Chen lnstitute of Polymers/Department of Chemist~ Nanchang University Nanchang Jiangxi 330031 China jiangxi Provincial Key Laboratory of New Energy Chemistry Nanchang University Nanchang Jiangxi 330031 China

Two novel donor-acceptor （D-A） copolymers containing dithienosilole （DTS） donor unit and ketone modified thieno[3,4-b]thiophene （TT） acceptor unit, namely, poly{4,4＇-bis（2-ethylhexyl）dithieno[3,2-b：2＇,Y-d]silole-5,5＇-diyl- alt-l-（thieno[3,4-b]thiophen-2-yl）-2-ethylhexan-l-one} （PDTSTT） and poly{4,4＇-bis（2-ethylhexyl）dithieno[3,2- b：2＇,3＇-d]silole-5,5＇-diyl-alt- 1-（4,6-bis（4-ethylhexylthien-2-yl）thieno[3,4-b]thiophen-2-yl）-2-ethylhexan- 1-one} （PD- TSDTTT）, were synthesized for the application in polymer solar cells （PSCs）, and the effects of thiophene bridge on the structural geometry and photovoiltaie performance have been investigated. The polymer PDTSTT and PDTSDTTT have the electrochemical bandgaps of 1.54 and 2.02 eV, together with low-lying HOMO energy levels of-5.47 and -5.37 eV, respectively. molecular geometry simulation result shows that compared with PDTSTT, the insertion of thiophene bridge in PDTSDTTT can well relieve the steric hindrance between the TT and DTS unit, as confirmed by the reduced dihedral angle between DTS and DTTT unit. Under the illumination of AM 1.5G, 100 mW/cm2, the PSC based on PDTSDTTT/PC61BM （1 ： 1, w ： w） demonstrates a power conversion efficiency of 1.0%, which is significantly improved in comparison with the device based on PDTSTT/PC61BM （1 ： 2, w ： w） under the same experimental condition. This is because the enhanced planarity and increased effective conjugation of the main chain in PDTSDTTT promote the more favorable morphology for charge transportation, although PDTSTT possesses the broader absorption band than PDTSDTTT.

关键词： donor-acceptor copolymer molecular geometry photovoltaics

Theoretical study on tetrazole and its derivatives (3) MP2 and thermodynamic calculations of amino derivatives of tetrazole

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Chinese Journal of Chemistry 1999年第2期17卷 114-124页

作者：陈兆旭肖鹤鸣高宝华 Department of Chemistry Nanjing university of Science and Technology Nanjing Jiangsu 210094 China

Fully optimized geometries and electronic structures of amino derivatives of tetrazole are obtained at MP2/6-31G* level. The tetrazole rings are planar and aromatic for all the amino derivatives of tetrazole. The amino group is not co-planar with the ring and its conformation is mainly determined by the lone pair electronic repulsion between the substituents and the ring. N(4) atom is more negatively charged and is the most probable coordination site. The energy gaps between LUMOs and HOMOs of 2H-aminotetrazoles and C-aminotetrazole neutrals are smaller than those of the corresponding 1H-isomers and N-aminotetrazole neutrals respectively. The IR frequencies, thermodynamic properties and temperature-dependent functions for heat capacities in the fom (a + bT + cT2) in the 300–1000K range are reported.

关键词： Tetrazole derivatives ab initio method molecular geometry IR spectra thermodynamic property

Theoretical Studies on Property and Structure of Silacyclohexane-based Liquid Crystal Compounds

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Chinese Journal of Structural Chemistry 1998年第2期17卷 129-132页

作者： YI Xing-Huan YI Xue-Feng GONG Xue-Dong XIAO He-Ming(Department of Chemistry, Nanjing University of Science & Technology, Nanjing 210094) 南京理工大学化学系江苏南京

SCF-MO-AM1 calculations have been per formed on 10 silacyclohex-ane-based liquid crystal compounds by energy gradient completed optimization. The stable configurations, electronic structures, heats of formation, dipole moments and ionization potentials of titled comPounds are first reported. The calculated results *** relating to the classical organic electronic theory.

关键词： silacyclohexane-based compounds liquid crystal AM1 method molecular geometry heat of formation