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Electron Transfer Reaction between M-C_6H_6 and M^+-C_6H_6 Complexes in the Gas Phase: Density Functional Theory Study

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Chinese Chemical Letters 2000年第3期11卷 219-222页

作者： Ai Ping FU, Dong Mei DU, Zheng Yu ZHOU (Department of Chemistry, Qufu Normal university,shandong. Qufu 273165 state key laboratory crystal materials shandong university, shandong. jinan 2.0100) Qufu Normal Univ Dept Chem Shandong 273165 Qufu Peoples R China shandong Univ State Key Lab Crystal Mat Jinan 250100 Peoples R China

DFT/BLYP method is used to theoretically investigate the electron transfer (ET) reactions between M (Li, Na, Mg)-C_6H_6 and M+-C_6H_6 complexes in the gas phase. The geometry optimization of the precursor complexes and the transition state in the process of ET reaction was performed at 6-31G basis set level. The activation energy. the coupling matrix element and the rate constant of the ET reaction are calculated at semi-quantitative level.

关键词： M-C_6H_6 complex density functional theory rate constant.

Micromechanical analysis of interaction energy for SMA reinforced composite

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Science China(Technological Sciences) 2009年第3期52卷 610-616页

作者： ZHU YuPing1,2, DUI GuanSuo1 & DUO Liu3 1 Institute of Mechanics, Beijing Jiaotong university, Beijing 100044, China 2 Department of Engineering Mechanics, Jiangsu university, Zhenjiang 212.13, China 3 state key lab of crystal materials, shandong university, jinan 2.0100, China Institute of Mechanics Beijing Jiaotong University Beijing 100044 China Department of Engineering Mechanics Jiangsu University Jiangsu Zhenjiang 212013 China state key lab of crystal materials Shandong University Jinan 250100 China

The energy of the interaction between the matrix and the inclusions in shape memory alloy (SMA) re- inforced composite is one of the most important and complicated parts in thermodynamic constitutive theory. In this paper, the interaction energy is derived based on the classical theory of micromechanics and the thermodynamic theory. The SMA composite is treated as three phases, namely the austenitic phase, the martensite phase and the matrix phase. The interaction among the three phases is analyzed in a way close to the fact. The present expression is used to calculate the interaction energy of a typical SMA composite with attentions paid to understand of the effects of the matrix material, the fiber ge- ometry, and the fiber/matrix volume ratio. It is shown that the method developed in this paper is credible compared with the references. Some useful conclusions are obtained.

关键词： shape memory alloy interaction energy SMA composite micromechanics thermodynamics

A first-principles study of dihydroazulene as a possible optical molecular switch

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Science China(Physics,Mechanics & Astronomy) 2011年第3期Mechanics & Astronomy) .卷 437-441页

作者： XIA CaiJuan1, LIU DeSheng2,3 & LIU HanChen1 1 School of Science, Xi’an Polytechnic university, Xi’an 710048, China 2 School of Physics, state key laboratory of crystal materials, shandong university, jinan 2.0100, China 3 Department of Physics, Jining university, Qufu 273155, China 1. School of Science Xi’an Polytechnic University Xi’an 710048 China2. School of Physics State Key Laboratory of Crystal Materials Shandong University Jinan 250100 China3. Department of Physics Jining University Qufu 273155 China

By applying nonequilibrium Green's function formalism combined with first-principles density functional theory, we investigate the electronic transport properties of the dihydroazulene optical molecular switch. Three kinds of adsorption sites including the hollow, bridge and top sites are studied. The two forms of this molecule, namely the open form and the closed form, can reversibly switch from each other upon photoexcitation. Their transmission spectra are remarkably distinctive. Theoretical results show that the current of the closed form is always significantly larger than that of the open form for all three adsorption sites, which promises this system as possibly one of the good candidates for optical switches due to its unique advantage, and which may have some potential applications in the future molecular circuit.

关键词： molecular switch nonequilibrium Green’s function electronic transport density functional theory

Theory Study on Structures and Vibrational Frequencies of Pyruvic acid

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Chinese Chemical Letters 2000年第5期11卷 447-450页

作者： Dong Met DU Ai Ping FU Zheng Yu ZHOU (Department of Chemistry. Qufu Normal university. shandong. Qufu 273165 state key laboratory crystal materials shandong university.shandong. jinan 2.0100) Qufu Normal Univ Dept Chem Shandong 273165 Oufu Peoples R China shandong Univ State Key Lab Crystal Mat Jinan 250100 Peoples R China

Density functional theory BLYP (using Becke's and Lee-Yang-Pars's correlation functionals), ab initio Hartree-Fock (HF) and hybrid DFT/HF B3LYP calculations were carried out to study the structure and vibrational spectra of pyruvic acid. The scaled B3LYP/6-31G* frequencies correspond well with available experimental assignment of the functional vibrational modes and the mean absolut devation is only 12.3cm^(-1).

关键词： Density functional theory vibrational spectra pyruvic acid

Theoretical Study on the Structure and Vibrational Spectra for 4-methyl-3-penten-2-one

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Chinese Chemical Letters 1999年第10期10卷 835-838页

作者： Dong Mei DU Ai Ping FU Zheng Yu ZHOU (Department of Chemistry. Qufu Normal university, shandong, Qufu 273165 2 state key laboratory of crystal materials. shandong university, shandong, jinan 2.0100) Qufu Normal Univ Dept Chem Shandong 273165 Qufu Peoples R China shandong Univ State Key Lab Crystal Mat Jinan 250100 Peoples R China

Density functional theory BLYP (using Becke's and Lee-Yang-Parr's correlation functionals), nb initio Hartree-Fock (HF) and hybrid DFT/HF B3LYP calculations were carried out to study the structure and vibrational spectra of 4-methyl-3-penten-2-one. The BLYP/6-31G* and scaled HF/6-31G* frequencies correspond well with each other and with available experimental assignment of the functional vibrational modes.

关键词： density functional theory vibrational spectra 4-methyl-3-penten-2-one

Synthesis, Structure and Transesterification of the Derivatives of β-Alkoxycarbonylethyltin Trichlorides with Diethyldithiocarbamate

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Chinese Chemical Letters 2000年第6期11卷 517-520页

作者： Lai Jin TIAN Bin ZHAO Zheng Yu ZHOU Min XIA Wen Tao YU Ping YANG(Department of Chemistry, Qufu Normal university, shandong, Qufu 273165)(state key laboratory crystal materials shandong university, shandong, jinan 2.0100) Qufu Normal Univ Dept Chem Shandong 273165 Qufu Peoples R China shandong Univ State Key Lab Crystal Mat Jinan 250100 Peoples R China

The derivatives of β-alkoxycarbonylethyltin trichlorides with diethyldithiocarbamate,ROCOCH2CH2Sn(S2CNEt2)Cl2, were synthesized and characterized by the means of elemental analysis, IR, 1H NMR and X-ray single crystal diffraction. The structural features of the compounds were described, and the possible mechanism of transesterification for compound 2a was suggested.

关键词： β-Aalkoxycarbonylethyltin trichloride diethyldithiocarbamate crystal structure,transesterification

Density Functional Study on the Vibrational Frequencies of Hydrazoic Acid and Methyl Azide

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Chinese Chemical Letters 1999年第7期10卷 619-622页

作者： Ai Ping FU Dong Mei DU Zheng Yu ZHOU (Department of Chemistry Qufu Normal university. shandong. Qufu. 273165)(state key laboratory crystal materials shandong university, shandong. jinan. 2.0100) Qufu Normal Univ Dept Chem Shandong 273165 Qufu Peoples R China shandong Univ State Key Lab Crystal Mat Jinan 250100 Peoples R China

Harmonic vibrational frequencies of hydrazoic acid and methyl azide are calculated using HF. MP2 methods and five popular density functional (DFT) methods and compared with experimental results. Of these seven methods, BLYP reproduces the observed frequencies most satisfactorily, while the results in HF and MP2 are worse. These indicate the BLYP calculation is a very promising approach for understanding the observed spectral features.

关键词： density functional theory vibrational spectra hydrazoic acid methyl azide

SOS Calculation of Nonlinear Optical Propertiesof Synthesized ASPBPh_4

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Chemical Research in Chinese Universities 2001年第2期17卷 207-211页

作者： ZHAO Xian, TIAN Yu-peng, ZHOU Yu-fang and JIANG Min-hua (state key laboratory of crystal materials, shandong university, jinan 2.0100, P. R. China) LIU Yong-jun and HU Hai-quan (Institute of Theoretical Chemistry, shandong university, jinan 2.0100) 山东大学晶体材料国家重点实验室山东济南 250100 山东大学山东济南 250100

The two-photon absorption induced lasing spectrum shows that the synthesized ASPBPh4, trans-4- [p- (N-methyl-N- (hydroxyethyl)amino) styryl]-N-methylpyridinium, has a distinct ef- ficiency of laser frequency up-conversion. This nonlinear optical property of such a kind of com- pounds is related to two-photon absorption (TPA). In our work, we used the intermediate ne- glect of differential overlap (INDO) plus single-excitation configuration interaction (SCI) method to get the basic properties of the molecule, and calculated the second hyperpolarizability and the cross section of two-photon absorption by means of sum-over-state (SOS) expression. The rela- tionship between the structure and the properties is discussed.

关键词： Two-photon absorption Semiempirical method Sum-over-state

Lattice Effects and Irreversible Magnetoresistance in Gd Doped La-Ca-Mn-O

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Journal of materials Science & Technology 2002年第6期18卷 509-512页

作者： Baoxin HUANG, Yihua LIU, Ruzhen ZHANG, Chengjian WANG, Gang JI and Liangmo MEIDepartment of Physics and state key laboratory of crystal materials, shandong university, jinan, 2.0100, China shandong Univ Dept Phys Jinan 250100 Peoples R China shandong Univ State Key Lab Crystal Mat Jinan 250100 Peoples R China

The Gd substituting effects for La in La0.67Ca0.33MnO3 has been studied. With increasing the substituting amount of Gd, the phase transition temperature of metal-isolator for the samples decreases, the corresponding peak resistivity increases, the Curie temperature decreases monotonically. The substitution of La-Ca-Mn-O with 11% Gd for La improved the magnetoresistance ratio by an order of magnitude. The effects of substituting Gd can be explained in terms of the lattice effects. An irreversible MR behaviour was observed in Gd-substituting compounds. This effect became marked when the substituting amount of Gd was greater than 7%. A maximum irreversible increment of MR ratio as large as 91% was obtained when Gd substituting amount was 11%.

关键词： Manganese perovskites Colossal magnetoresistance Lattice effect Irreversible magnetoresistance