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intermolecular [4+3] Cycloaddition of Cyclic Oxyallyl

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Chinese Chemical Letters 1997年第7期8卷 563-564页

作者： Hu, YH Bai, DL CHINESE ACAD SCI SHANGHAI INST MAT MEDSHANGHAI 200031PEOPLES R CHINA

The [4+3] cycloaddition of the 6-substituted-2-chlorocyclohexanone and furans under the Fohlish conditions (Et3N in CF3CH2OH) has been accomplished to give tricyclic cycloadducts with good yields.

关键词： KBr IR cm MS MHz intermolecular Cycloaddition of Cyclic Oxyallyl

Enhanced intermolecular interactions to improve twisted polymer photovoltaic performance

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Science China Chemistry 2019年第3期62卷 370-377页

作者： Cunbin An Jingming Xin Lanlan Shi Wei Ma Jianqi Zhang Huifeng Yao Sunsun Li Jianhui Hou Beijing National Laboratory for Molecular Sciences State Key Laboratory of Polymer Physics and Chemistry Institute of Chemistry Chinese Academy of Sciences State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University Key Laboratory of Nanosystem and Hierarchical Fabrication National Center for Nanoscience and Technology University of Chinese Academy of Sciences

In polymer solar cells(PSCs), twisted polymer donors usually have low photovoltaic efficiencies due to their poor photoactive layer morphologies. Herein, we successfully improved twisted polymer(PBDT-3T) photovoltaic efficiency by employing C=O groups(PBDT-3TCO) to enhance intermolecular interactions. The maximum power conversion efficiency(PCE) of PBDT-3T is only 1.05%, while the PCE of PBDT-3TCO reaches 11.77% in non-fullerene(NF) PSCs. Both polymers-based PSCs show very similar open-circuit voltages but remarkable differences in their short-circuit currents and fill factors. The single crystals of both functionalized terthiophenes with methyl substituents demonstrate that the terthiophene with C=O units changes molecular pattern by forming intra/inter molecular S???O and O???H interactions but its molecular planarity does not significantly improve.Our comparative studies show that PBDT-3TCO with C=O units possesses a strong aggregation property and optimal photoactive layer morphology in NF PSCs. This study provides important insight into the design of high-performance twisted polymer donors for NF PSCs.

关键词： twisted polymer donors carbonyl group intermolecular interaction polymer solar cells

A new method for quick predicting the strength of intermolecular hydrogen bonds

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Science China Chemistry 2009年第2期52卷 153-160页

作者： SUN ChangLiang ZHANG Yan JIANG XiaoNan WANG ChangSheng YANG ZhongZhi Department of Chemistry Liaoning Normal UniversityDalian 116029China

A new method is proposed to quick predict the strength of intermolecular hydrogen bonds.The method is employed to produce the hydrogen-bonding potential energy curves of twenty-nine hydro-gen-bonded dimers.The calculation results show that the hydrogen-bonding potential energy curves obtained from this method are in good agreement with those obtained from MP2/6-31+G calculations by including the BSSE correction,which demonstrate that the method proposed in this work can be used to calculate the hydrogen-bonding interactions in peptides.

关键词： intermolecular hydrogen bonds hydrogen-bonded dimer hydrogen-bonding potential energy curves

Advances in high-resolution nuclear magnetic resonance methods in inhomogeneous magnetic fields using intermolecular multiple quantum coherences

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Science China(Physics,Mechanics & Astronomy) 2009年第1期52卷 58-69页

作者： CHEN Zhong LIN MeiJin CHEN Xi CAI ShuHui Departments of Physics State Key Laboratory of Physical Chemistry of Solid SurfaceXiamen UniversityXiamen 361005China

Strong and extremely homogeneous static magnetic field is usually required for high-resolution nu-clear magnetic resonance (NMR). However, in the cases of in vivo and so on, the magnetic field inho-mogeneity owing to magnetic susceptibility variation in samples is unavoidable and hard to eliminate by conventional methods such as shimming. Recently, intermolecular multiple quantum coherences (iMQCs) have been employed to eliminate inhomogeneous broadening and obtain high-resolution NMR spectra, especially for in vivo samples. Compared to other high-resolution NMR methods, iMQC method exhibits its unique feature and advantage. It simultaneously holds information of chemical shifts, multiplet structures, coupling constants, and relative peak areas. All the information is often used to analyze and characterize molecular structures in conventional one-dimensional NMR spec-troscopy. In this work, recent technical developments including our results in this field are summarized; the high-resolution mechanism is analyzed and comparison with other methods based on interactions between spins is made; comments on the current situation and outlook on the research directions are also made.

关键词： nuclear magnetic resonance high-resolution inhomogeneous magnetic fields intermolecular multiple quantum coherence

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Science China Chemistry 2004年第6期47卷 466-479页

作者： SONG Huajie1,2, XIAO Heming1 & DONG Haishan2 1. Department of Chemistry, Nanjing University of Science and Technology, Nanjing 210094, China 2. Institute of Chemical Materials, China Academy of Engineering Physics, Mianyang 621900, China Department of Chemistry Nanjing University of Science and Technology Nanjing China Institute of Chemical Materials China Academy of Engineering Physics Mianyang China

The symmetry-adapted perturbation theory (SAPT) that has the ability in decompo- sition of the total interaction energy into physically meaningful components is used to provide a more fundamental understanding of intermolecular forces. This work was motivated by the diffi- culty of standard SAPT in computing the intermolecular interactions for large energetic dimer systems. SAPT based on Kohn-Sham orbitals (SAPT(DFT)) proves computationally efficient for these large systems, but has been shown to perform poorly for interaction energy components. The deficiencies of SAPT(DFT) result from wrong asymptotical behaviors of commonly used exchange-correlation potentials. To remove the deficiencies, two asymptotic corrections by means of van Leeuwen and Baerends (LB) model potential and Fermi-Amaldi (FA) type potential were applied into three small test systems comprising He2, HF2 and (N2)2 and a set of larger ni- tramide dimers at several separations. The results showed that when utilizing newly developed frequency-dependent density susceptibilities (FDDS) technique for computing dispersion energy, the FA asymptotic correction is very effective to circumvent these deficiencies in SAPT(DFT) and yields a good accuracy over the LB correction. The FA corrected SAPT(DFT) approach is capa- ble of correctly predicting all the quantitative trends in binding energies for all test cases and substantially reduces computational cost as compared with the standard SAPT calculations. The successful application of the approach to nitramide dimer demonstrates that it potentially pro- vides a good means to calculate accurately intermolecular forces in larger system such as en- ergetic systems.

关键词： intermolecular interaction, density functional theory (DFT), symmetry adapted perturbation theory (SAPT), asymptotic correction, frequency-dependent density susceptibilities (FDDS).

Ab initio intermolecular potential energy surface of He-LiH

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Science China Chemistry 1997年第5期40卷 554-560页

作者：鄢国森杨明晖谢代前 Department of Chemistry Sichuan UniversityChengdu 610064China

The intermolecular potential energy surface of He-LiH complex was studied using the full-electronic complete forth-order Miller-Plesset perturbation (MPPT) method.In ab initio calculations,the bond length of LiH was fixed at 0 159 5 nm.The potential has two local minima of Vm=-179.93 cm for the linear He LiH geormetrv at Rm=0.227 nm and Vm=-10.44 cm-1 for the linear He-HL1 geometry at Rm=0.516 nm The potemal exhibits strong anisotropy The analytic potential function with 31 parameters was determined by fitting to the calculated ab,mtio potentials The influence of variation of LiH bond length on the potential energy surface was also

关键词： intermolecular interaction He-LiH quantum chemistry ab initio calculation MPPT method

AN INVESTIGATION ON THE ab initio CALCULATION OF intermolecular INTERACTION——NON-BONDED INTERACTION IN THE HYDROGEN BOND COMPLEX (HF)_2

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Science China Chemistry 1990年第7期33卷 795-800页

作者：严继民 Institute of Chemistry Academia Sinica Beijing 100080 PRC

An ab initio calculation of the hydrogen bond complex （HF）2 is given with the 6-311 G** basis set, according to which the potential surface around the balance point of the distancès and the orientations between two HF molecules is obtained. The atomic charges in the system are calculated with the PD/LSF method （potential-derived/least-square-fitting method） and then an analysis of the hydrogen bond interaction between two HF molecules is given with the （exp-6-1） potential function, by means of which it is shown that the main interaction between them is not an electro-static but a charge transfer one. The potential curve between two HF molecules is like a Morse function.

关键词： intermolecular interaction ab initio calculation hydrogen bond hydrogen fluoride dimers PD/LSF method

THE　SYNTHESIS　OF　4，5－BIS（4＇－BROMOBENZYLTHIO）－1，3－DITHIOLE－2－THIONE　WITH　ONE　DIMENSIONAL　intermolecular　INTERACTIONS

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Chinese Chemical Letters 1996年第2期7卷 103-104页

作者： Fang QI(Institute of Crystal Materials, Shandong University, Jinan, 250100) Institute of Crystal Materials Shandong University Jinan 250100 China

The title compound BBBT-Dry (C17H12Br2S5, Mr=536.42) has been synthesized and its structure feature has been described. BBBT-DTT is characterized by one dimensional chains formed by S…S (head to head) and Br…Br (tai... 详细信息

关键词： BIS THIONE WITH intermolecular INTERACTIONS OF SYNTHESIS DITHIOLE DIMENSIONAL BROMOBENZYLTHIO

Study of intermolecular Interactions in Liquid Crystals: Para-butyl-p’-cyano-biphenyl

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Journal of Crystallization Process and Technology 2014年第1期4卷 31-38页

作者： K. K. Dwivedi M. K. Dwivedi S. N. Tiwari Department of Physics D.D.U. Gorakhpur University Gorakhpur India.

Various characteristics of mesomorphism can be explained using intermolecular interactions between a pair of liquid crystalline molecules. The intermolecular interactions have been calculated considering multipole-multicentere expansion method and modified by second order perturbation treatments. For calculation of multipole i.e. charge, dipole, etc. at each atomic center of molecules, para-butyl-p’-cyano-biphenyl, GAMESS, an ab initio program, with 6-31G* basis set has been used. The stacking, in-plane and terminal interaction energies explain the liquid crystalline behaviour of the system.

关键词： Liquid Crystals Phase Transition intermolecular Interactions GAMESS Multicentred-Multipole Expansion