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Synthesis, Structure and Non-linear Optical Properties of Iron Mercury Tetrathiocyanate

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Chinese Chemical Letters 1998年第12期9卷 0-0,0-0页

作者： Yun Xing YAN Qi FANG Wen Tao YU Yu Peng TIAN Duo Rong YUAN Xin Qiang WANG Fan Qing MENG (institute of crystal materials and State key laboratory of crystal materials,shandong university, jinan, 2.0100)Zhi Gang CAI Ling Zhi ZHANG (institute of Laser shandong Univ Inst Crystal Mat Jinan 250100 Peoples R China shandong Univ State Key Lab Crystal Mat Jinan 250100 Peoples R China Zhongshan Univ Inst Laser Spect Guangzhou 510275 Peoples R China Zhongshan Univ State Key Lab Ultrafast Laser Spect Guangzhou 510275 Peoples R China

Iron Mercury Tetrathiocyanate (FeHg(SCN)4) has been synthesized and its structure hasbeen detendned. It belongs to the tetragonal system, 14 space group. The Hg-S-C=N-Fe bridgeleeds to the formation of an infinite three dimensional network. Irrsdiated by a 1.064 nm Nd:YAG laser beam, FeHg(SCN)4 showed a 0.532 nm second harmonic intensity which is 0.6 times asthat of organic nonlinear optical crystal urea.

关键词： FeHg(SCN)_4 synthesis structure nonlinear property

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

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 212013, 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

Synthesis, Structure and Non-linear Optical Properties of Manganese Mercury Tetrathiocyanate

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Chinese Chemical Letters 1999年第3期10卷 257-260页

作者： Yun Xing YAN Qi FANG Duo Rong YUAN Yu Peng TIAN Zhi LIU Xiao MeiWANG Min Hua JIANG D. WILLIAMS A. SIU Zhi Gang CAI (institute of crystal materials and State key laboratory of crystal materials,shandong university. jinan 2.0100)(Department of Chem shandong Univ Inst Crystal Mat Jinan 250100 Peoples R China shandong Univ State Key Lab Crystal Mat Jinan 250100 Peoples R China Hong Kong Univ Sci & Technol Dept Chem Hong Kong Peoples R China Zhongshan Univ Inst Laser Spect Guangzhou 510275 Peoples R China Zhongshan Univ State Key Lab Ultrafast Lase Spect Guangzhou 510275 Peoples R China

The title copound Manganese Mercury Tetrathiocyanate (MnHg (SCN)(4)) has been synthesized and its structure has been determined. It belongs to tetragonal system, I (4) over bar space group. The cell dimensions are: a = 1.1324 (3) nm, c = 0.4270 (2) nm, V = 0.5475 (3) nm(3), Z = 2, D-c = 2.959 g/cm(3), R = 0.028, R-w = 0.037. The structure feature of the crystal is the Hg-S-C=N-Mn bridge which leads to the formation of an infinite three dimensional network. Irradiated by a 1064 nm Nd:YAG laser beam, MnHg (SCN), shows a 532 nm second harmonic intensity which is 18 times as that of organic nonlinear optical crystal urea, and therefore shows a quite promising application value as a useful nonliear optical material.

关键词： MnHg (SCN)(4) synthesis structure nonlinear optical property

Capped carbon nanotube-based molecular switch

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Science Bulletin 2010年第13期55卷 1227-1230页

作者： ZHAO Peng1, WANG PeiJi1, ZHANG Zhong1 & LIU DeSheng2 1 School of Science, university of jinan, jinan 250022, china 2 School of Physics, State key laboratory of crystal materials, shandong university, jinan 2.0100, china School of Science University of Jinan Jinan 250022 China School of Physics State Key Laboratory of Crystal Materials Shandong University Jinan 250100 China

Using the Landauer formalism that combines both the non-equilibrium Green's function (NEGF) and first-principles density functional theory (DFT), the electron transport characteristics of one-dimensional molecular switching device based on the capped carbon nanotubes have been investigated. The results show that the transmission can be efficiently tuned within two orders of magnitude just by changing 0.2 nm of the tube-tube separation. Moreover, the electron transport is insensitive to the topology of the facing conformations which can improve the practical stability of the chosen system as a molecular switch.

关键词： carbon nanotube molecular switch non-equilibrium Green function density functional theory

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

Large second-order optical nonlinearities of s-triazine derivatives: View from micro molecules to macro crystals

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Science china Chemistry 2005年第3期48卷 203-209页

作者： FANG Qi1, LEI Hong2, CUI Yuezhi3, HUANG Zhenli4, XUE Gang1 & YU Wentao1 1. State key laboratory of crystal materials, shandong university, jinan 2.0100, china 2. School of Information Science and Engineering, shandong university, jinan 2.0100, china 3. Department of Chemical Engineering, Light Industry College of shandong, jinan 2.0100, china 4. key laboratory of Biomedical Photonics, Ministry of Education, Huazhong university of Science and Technology, Wuhan 430074, china 1. State key laboratory of crystal materials Shandong University 250100 Jinan China 2. School of Information Science and Engineering Shandong University 250100 Jinan China 3. Department of Chemical Engineering Light Industry College of Shandong 250100 Jinan China 4. key laboratory of Biomedical Photonics Ministry of Education Huazhong University of Science and Technology 430074 Wuhan China

Three s-triazine derivatives have been synthesized and their structures been de-termined. These are Compound I: 2,4-dimethyl-6-(p-N,N-dimethylaminostyryl)-s-triazine (abbre-viated to NMe-1), Compound II: 2,4-dimethyl-6-(p-N,N-diethylaminostyryl)-s-triazine (to NEt-1), and Compound III: 2-methyl-4,6-bis(p-N,N-dimethylaminostyryl)-s-triazine (NMe-2). NMe-1 and NEt-1 molecules belong to the D-π-A type with a one-dimensional charge-transfer character. NMe-1 crystallizes to centrosymmetric P1 space group, while NEt-1 to non-centrosymmetric polar Cc space group with all of the molecular charge-transfer axes taking the same orientation. Under the irradiation of 1064 nm fundamental laser, NEt-1 powder crystals radiate a 2-order harmonic light with an intensity 46.8 times that of urea. The Λ typed NMe-2 molecule, which has a two-dimensional charge-transfer character, crystallizes to polar P21 space group. Its powder crystals exhibit a 2-order harmonic intensity 46.2 times that of urea. The quantum chemical cal-culations and tensor analyses have been carried out to reveal the dependence of the macro 2-order nonlinear optical (NLO) efficiency on the micro 2-order NLO coefficients (β) and on the crystalline packing styles.

关键词： s-triazine derivatives, synthesis, structure, SHG intensities of crystals, βvalues of molecules.

Irreversible Colossal Magnetoresistance in La_(0.58)Dy_(0.09)Ca_(0.33)MnO_3

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Journal of materials Science & Technology 2003年第6期19卷 622-624页

作者： Baoxin HUANG, Yihua LIU, Ruzhen ZHANG, Youyong DAI, Chengjian WANG, Xiaobo YUAN and Liangmo MEIDepartment of Physics and State key laboratory of crystal materials, shandong university, Ji’nan 2.0100, china Lab. of crystal Mat. Dept. of Phys. Shandong Univ. Ji'nan 250100 China

The representative sample La0.58Dy0.09Ca0.33MnO3 of Dy doped La0.67Ca0.33MnO3 rare-earth manganites was investigated. The most important effect of Dy doping is to introduce the magnetoimpurity and form the spin clusters which induce dramatically large CMR in La0.58Dy0.09Ca0.33MnO3. The fitting results of field-induced resistivity decrease to the Brillouin function indicate that the CMR is caused by the spin dependent hopping between spin clusters. It is the magnetic field that reduces the size of spin clusters and induces a field-induced irreversible CMR behaviour.

关键词： Spin cluster Magnetoimpurity Colossal magnetoresistance