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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 {2. materials, shandong university, jinan 2501.0, P. R. china) LIU Yong-jun and HU Hai-quan (Institute of Theoretical Chemistry, shandong university, jinan 2501.0) 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

Mutually　Pumped　Phase　Conjugation　of　Three　Incoherent　Beams　with　a　Novel　Photorefractive　crystal

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Chinese Journal of Lasers 1996年第3期B5卷 235-241页

作者： ZHANG Liangmin SHAO Zongshu ZHANG Jingwen MU Xiaodong CHEN Huanchu JIANG Minhua(national laboratory of {2. materials, shandong university, jinan 2501.0) shandong Univ Jinan China

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Ｍｕｔｕａｌｌｙ　Ｐｕｍｐｅｄ　Ｐｈａｓｅ　Ｃｏｎｊｕｇａｔｉｏｎ　ｏｆ　Ｔｈｒｅｅ　Ｉｎｃｏｈｅｒｅｎｔ　Ｂｅａｍｓ　ｗｉｔｈ　ａ　Ｎｏｖｅｌ　Ｐｈｏｔｏｒｅｆｒａｃｔｉｖｅ　ＣｒｙｓｔａｌＭｕｔｕａｌｌｙＰｕｍｐｅｄＰｈａｓｅＣｏｎｊｕｇａｔｉｏ...

关键词： photorefractive phase conjugation mutually pumped phase conjugation

Structural relaxation of metallic glass forming melts

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Science china(Physics,Mechanics & Astronomy) 2010年第3期53卷 405-408页

作者： BIAN XiuFang, QIN JingYu & QIN XuBo key laboratory for Liquid-Solid Structural Evolution and Processing of {2. (Ministry of Education), shandong university, jinan 2.0061, china 1. key laboratory for Liquid-Solid Structural Evolution and Processing of {2. (Ministry of Education) Shandong University Jinan 250061 China

The fragility of superheated melts, M, for 13 kinds of metallic alloys has been evaluated from the data of the dynamic viscosity above their liquidus temperatures. The authors find that the glass forming ability of metallic melts depends on the fragility of superheated melts rather than on the value of viscosity. In the present work the value of fragility is less than 1 for good glass-forming melts but more than 1 for the other melts. The variation rate of atomic coordination number with temperature indicates clearly the relaxation rate of molten structures. The fragility of superheated melts is found in good agreement with the variation rate of the atomic coordination number with temperature.

关键词： structural relaxation metallic glasses melts

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 2.3165 State {2. laboratory crystal materials shandong university.shandong. jinan 2501.0) 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

Negative differential resistance in molecular devices: the role of molecule-electrode coupling

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Science china(Physics,Mechanics & Astronomy) 2011年第8期Mechanics & Astronomy) .卷 1455-1460页

作者： ZHAI YaXin1, JI GuoMin1, FANG ChangFeng1, CUI Bin1, ZHAO Peng2.& LIU DeSheng1,3, 1 School of Physics, State key laboratory of {2. materials, shandong university, jinan 2501.0, china 2.School of Science, university of jinan, jinan 2.002., china 3 Department of Physics and Information Engineering, Jining university, Qufu 2.3100, china 1. School of Physics State Key Laboratory of Crystal Materials Shandong University Jinan 250100 China2. School of Science University of Jinan Jinan 250022 China3. Department of Physics and Information Engineering Jining University Qufu 273100 China

By applying nonequilibrium Green's function formalism combined with the first-principles density functional theory, we investigate the electronic transport in two molecular junctions constituted by a substituted oligo (phenylene ehtynylene) sand-wiched between two Au electrodes. Our calculations show that the weak molecule-electrode coupling is responsible for the observation of the negative differential resistance (NDR) effect in experiments. When the coupling is weak, the projected density of states (PDOS) of the molecule and the electrodes undergoes a mismatch-match-mismatch procedure, which increases and then decreases the transmission peak intensities, leading to a NDR effect. We also find that the localization/delocalization of the molecular orbitals and the change of charge state of the molecule have no direct relation with the NDR effect, because they change little as the voltage increases.

关键词： negative differential resistance substituted oligo (phenylene ehtynylene) molecular junction density functional theory nonequilibrium Green’s function formalism

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 2.2.13, china 3 State key Lab of crystal materials, shandong university, jinan 2501.0, 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 {2. 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

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 2.3165)(State {2. laboratory crystal materials shandong university, shandong, jinan 2501.0) 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,ROCOCH2.H2.n(S2.NEt2.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 2. was suggested.

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

Analysis of the carbon source for diamond crystal growth

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Chinese Science Bulletin 2008年第6期53卷 937-942页

作者： LI Li1,2. XU Bin2.3 & LI MuSen1,2.1 School of materials Science & Engineering, shandong university, {2. 2.0061, china 2.shandong Engineering Research Center for Super Hard materials, Zoucheng 2.3500, china 3 School of materials Science & Engineering, shandong Jianzhu university, {2. 2.0101, china School of materials Science & Engineering Shandong University Jinan China shandong Engineering Research Center for Super Hard materials Zoucheng China School of materials Science & Engineering Shandong Jianzhu University Jinan China

The lattice constants of diamond and graphite at high pressure and high temperature (HPHT) were calculated on the basis of linear expansion coefficient and elastic constant. According to the empirical electron theory of solids and molecules (EET), the valence electron structures (VESs) of diamond, graphite crystal and their common planes were calculated. The relationship between diamond and graphite structure was analyzed based on the boundary condition of the improved Thomas-Fermi-Dirac theory by Cheng (TFDC). It was found that the electron densities of common planes in graphite were not continuous with those of planes in diamond at the first order of approximation. The results show that during the course of diamond single crystal growth at HPHT with metal catalyst, the carbon sources forming diamond structure do not come from the graphite structure directly. The diamond growth mechanism was discussed from the viewpoint of valence electron structure.

关键词：钻石晶体生长石墨碳源价电子结构

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. 2.3165)(State {2. laboratory crystal materials shandong university, shandong. jinan. 2501.0) 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