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Ab initio Calculation of Intermolecular Dispersion Energy and Induction Energy of Nitramide Dimer

Chinese Journal of Chemistry 2004年第11期22卷 1377-1381页

作者：宋华杰肖鹤鸣董海山Institute of chemical materials {2. {3. Sichuan 62.900 china 黄奕刚Institute of chemical materials {2. {3. Sichuan 62.900 china 龙新平Institute of chemical materials {2. {3. Sichuan 62.900 china 汤业鹏Institute of chemical materials {2. {3. Sichuan 62.900 china Department of Chemistry Nanjing University of Science and Technology Nanjing Jiangsu 210094 China Institute of chemical materials China Academy of Engineering Physics Mianyang Sichuan 621900 China

The dispersion energies, induction energies and their exchange counterparts (exchange-dispersion and ex-change-induction energies) between two interacting nitramide molecules at several separations are derived based upon symmetry-adapted perturbation theory (SAPT). The results show that (1) the effect of intramonomer electron correlation on dispersion energies and induction energies for nitramide dimer system is remarkable especially in the region near the van der Waals minimum distance (0.42.nm). (2. At smaller separations the dispersion energies and the induction energies are largely quenched by their exchange counterparts, and this case in induction interaction is much more remarkable than in dispersion interaction. (3. Since at shorter distances there exists the strong short-range interaction due to electron transfer which quickly decays and even disappears at larger separations, the two different R-dependency formulae of induction energies were found: one is ca. R-12.7 at short distances, and the other ca. R-7.0 at large separations. The latter R-dependency is similar to that (ca. R-7.2. of dispersion. (4) In the case of strong polar interaction existing in nitramide dimer, the true induction correlation terms of higher order than t(2.)indE may be important.

关键词： dispersion energy induction energy nitramide dimer symmetry-adapted perturbation theory

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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 2.0094, china 2. Institute of chemical {2., {3., mianyang 62.900, china 1. Department of Chemistry Nanjing University of Science and Technology 210094 Nanjing China 2. Institute of chemical materials China Academy of Engineering Physics 621900 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).

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Electronic structure and magnetism of R(Fe,Si)_(12. (R=Y,Nd)

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Science china(physics,Mechanics & Astronomy) 2006年第2期49卷 195-202页

作者： SUN Guang’ai1, CHEN Bo1, DU Honglin2. FAN Zhijian1, GAO Tao3.& QI Xinhua3.. Institute of Nuclear {2. and Chemistry, china academy of engineering physics, mianyang 62.900, {3. 2. Department of {2., Peking university, Beijing 100871, {3. 3. Institute of Atomic and Molecular {2., Sichuan University, Chengdu 610065, {3. 1. Institute of Nuclear physics and Chemistry China Academy of Engineering Physics Mianyang 621900 China 2. Department of physics Peking university Beijing 100871 China 3. Institute of Atomic and Molecular physics Sichuan University Chengdu 610065 China

The newly developed full-potential linearized augmented plane wave (LAPW) and local orbitals (lo) based on standard APW methods are briefly introduced, and the structure and magnetic properties of R(Fe, Si)12.compounds (R = Y, Nd) are calculated using the method. The distribution of Si at different sites is analyzed based on total energy of one crystal unit with structure having been optimized. The characters of magnetic mo-ments, total density of states (TDOS) and partial density of states (PDOS) for different crystal sites Si occupies are obtained and analyzed. The results show that the total mag-netic moments of RFe10Si2.(R = Y, Nd) are larger than those of RFe10M2.(M = Ti, V, Cr, Mn, Mo and W) and the hybridization mechanism is seen as follows. Si(8j) reduce the mag-netic moments of Fe at three sites, however, Si(8f) mainly reduce the magnetic moments of Fe(8i) and Fe(8j) atoms. The Curie temperature is markedly enhanced by the introduc-tion of Si atoms according to spin fluctuation of DOS at Fermi level.

关键词： (L)APW+lo method R(Fe Si)12.R = Y Nd) magnetic moment Density of state.

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Theoretical study of ZnO adsorption and bonding on Al_2._3.0001) surface

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Science china(physics,Mechanics & Astronomy) 2004年第6期47卷 664-675页

作者： LI Yanrong1,YANG Chun1,2.XUE Weidong1,LI Jinshan3.& LIU Yonghua3.1.Institute of Microelectronics and Solid State Electronics,University of Electronic Science and Technol- ogy of {2.,Chengdu 610054,{2. 2.Institute of Mathematics and Software Science,Sichuan Normal University,Chengdu 610068,{2. 3.Institute of {3. materials,china academy of engineering physics,mianyang 62.000,{2. Institute of Microelectronics and Solid State Electronics University of Electronic Science and Technology of China Chengdu 610054 China Institute of Mathematics and Software Science Sichuan Normal University Chengdu 610068 China Institute of chemical materials China Academy of Engineering Physics Mianyang 621000 China

ZnO adsorption on sapphire (0001) surface is theoretically calculated by using a plane wave ultrasoft pseudo-potential method based on ab initio molecular dynamics. The results reveal that the surface relaxation in the first layer Al-O is reduced, even eliminated after the surface adsorption of ZnO, and the chemical bonding energy is 43..3.±3..6) kJ·mol?1. The chemical bond of ZnO (0.185 ± 0.01 nm) has a 3.° angle away from the adjacent Al-O bond, and the stable chemical adsorption position of the Zn is deflected from the surface O-hexagonal symmetry with an angle of about 3.°. The analysis of the atomic populations, density of state and bonding electronic density before and after the adsorption indicates that the chemical bond formed by the O2.of the ZnO ? and the surface Al3. has a strong ionic bonding characteristic, while the chemical bond formed by the Zn2. and the surface O2.has an obvious covalent characteristic, which ? comes mainly from the hybridization of the Zn 4s and the O 2. and partially from that of the Zn 3. and the O 2..

关键词： α-Al2.3.(0001) ZnO ab initio molecular dynamics chemical adsorption density of states

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An Absolute Method for Determination ofThermal Conductivities of Thermal Insulators by Microcalorimetry

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Journal of Thermal Science 1996年第2期5卷 93-98页

作者： Chen Xuelin(Institute of chemical materials, {2.,Chengdu 610003. {3.) Institute of chemical materials China Academy of Engineering Physics Chengdu China

Microcalorimetry was developed to determine thermal conductivities (λ) of thermal insulators with hollow cylindrical shapes. A special device of specimen with resistance threads wrapped on its surface and electric heater placed in its hole was designed to meet the needs of determiningλ without using standard substances to calibrate the instrument. A formula for calculating the value of λ was *** heating in the hole and on the surface of the specimen respectively, the values of λ can be obtained conveniently by this technique. The method was tested with teflon, plexiglass, quartz glass and polyethylene. The experimental values of λ for the four substances agree well with the literatures *** analysis was also made on the experimental data. It was found that the main factors affecting values of λ are: (1) The errors of determining the values of heat cumulated in specimen and materials in the space around it and (2. the errors of determining the values of inner and outer radii of cylindrical specimen.

关键词： thermal conductivity absolute method compensation microcalorimetry

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On-line parallel reversed phase two-dimensional liquid chromatography for high-throughput analysis of complex proteomic samples

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Science china Chemistry 2006年第6期49卷 527-533页

作者： WANG Zhicong1,3. ZHANG Qinghe2. LI Tong2. ZHAO Zhongyi3.& ZHANG Weibing1 1. Dalian Institute of {2. physics, Chinese academy of Sciences, Dalian 116011, {3. 2. Dalian Elite Analytical Instrument Co., Ltd., Dalian 116011, {3. 3. Faculty of Material Science and {2. engineering, {3. University of Geosciences, Wuhan 43.074, {3. 1. Dalian Institute of chemical physics Chinese Academy of Sciences Dalian 116011 China 3. Faculty of Material Science and chemical {2. China University of Geosciences Wuhan 430074 China 2. Dalian Elite Analytical Instrument Co. Ltd. Dalian 116011 China

A comprehensive two-dimensional liquid chromatographic system (2. SCX/RP) is con- structed with a 10-port-2.way valve using strong cation exchange chromatography (Hypersil SCX, 100 mm×4.6 mm I.D.) followed by reversed phase chromatography (Hypersil BDS C18, 15 mm×4.6 mm I.D.) to separate the complex peptides from globin peptic hydrolysate. After the sample was loaded on the SCX column, the phosphate buffer (pH 4.0) was used to elute the peptides. Then, elutes flowed through the interface and the peptides focused on the head of the trapping columns (Hypersil BDS C18, 15 mm×4.6 mm I.D.) but salt passed into the waste. After the valve was switched, the samples were flushed with a backward flow into the RP analytical column. The peptides on the SCX were eluted with 12.discontinuous steps linearly increasing salt concentrations. The peptides enriched on the trapping column were desalted and separated by the RP columns. The resolution and the resolved peaks of the 2. SCX/RP system were greatly increased and the total peak capacity reached as high as 2.80.

关键词： two-dimensional liquid chromatography, interface, trapping column, proteomics, globin.

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The Influence of Temperature on the Afterglow Feature of SrAl_2._4∶Eu,Dy Phosphors

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Journal of Wuhan University of Technology(materials Science) 2006年第3期21卷 120-122页

作者：王兵 materials School Southwest University of Science and TechnologyMianyang 621010China

Using a self-designed temperature testing box in which Xenon-lamp irradiation can be applied, the afterglow feature of SrAl2.4： Eu, Dy as a function of temperature has been researched. Two sorts of SrAl2.4 ： Eu, Dy phosphors, namely highest quality commercial one and the self-synthesized one by solid-state reaction process were employed. Results reveal a common phenomenon behaving as phosphorescent sudden extinguishments at a certain low temperature although their threshold temperature value （ about 2.3.K） has a slight difference . The general charueteristic for the influence of temperature on the afterglow feature presents, compared to the luminescent decay at room temperature （RT）, a bigger and faster decrease of phosphorescent brightness with the reduction of temperature, while decay curves still maitain the same pattern composed of a quick decline part and a platform falling part during which the phosphorescent brightness at 2.3.K is only aboat 1/2.as big as that at RT, and at 2.3.K the figure has changed to about 1/3. Finally , the reason of previous observed results has been analyzed briefly in theory.

关键词： afterglow SrAl2.4:Eu,Dy low temperature

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Studies on the analytical potential energy function of diatomic molecular ion XY^+ using variational method

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Science china(physics,Mechanics & Astronomy) 2004年第2期47卷 154-164页

作者： LIU Guoyue1,3. SUN Weiguo1,2.& FENG Hao1 1. Institute of physics, Sichuan University, Chengdu 610065, {2. 2. College of chemical {3., Sichuan University, Chengdu 610065, {2. 3. mianyang Teacher抯 College, mianyang 62.000, {2. Correspondence should be addressed to Sun Weiguo (e-mail: weiguosun@*** or guoyueliu@ ***) 1. Institute of physics Sichuan University 610065 Chengdu China 2. mianyang Teacher's College 621000 Mianyang China 3. College of chemical {2. Sichuan University 610065 Chengdu China

A new analytical potential energy function for diatomic molecular ion XY+ is proposed based on the energy consistent method (ECM). The Coulomb potential included in the new ionic potential contains multipole corrections, converges quickly and is variationally, changeable. The new potential and the ECM are applied to variationally studying the potential energies of eight electronic states of several diatomic molecular ions: the A2. state of CO+, the X2. g + state of Li 2.+ , the X2. g + state of He 2.+ , the 12.u state of Na 2.+ , the A2.u state of N 2.+ , the X1∑+ state of KrH+, the X2.+ state of SiO+ and the A2. state of SO+ ion. The present results agree excellently with the experiment-based Rydberg-Klein-Rees (RKR) potentials, and are superior to the commonly used Huxley-Murrell-Sorbie (HMS) analytical potentials, and are better in some cases than some quantum mechanicalab initio potentials in the ionic asymptotic and dissociation regions.

关键词： potential energy, diatomic ion, electronic state, variational method.

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Molecular dynamics simulations on the structures and properties of ε-CL-2.-based PBXs ——Primary theoretical studies on HEDM formulation design

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Science china Chemistry 2007年第6期50卷 737-745页

作者： XU XiaoJuan1,2. XIAO JiJun1, HUANG Hui3. LI JinShan3.& XIAO HeMing1 1 Department of Chemistry, Nanjing University of Science and Technology, Nanjing 2.0094, {2. 2.Department of Chemistry, Yancheng Teacher’s College, Yancheng 2.4002. {2. 3.Institute of chemical {3., china academy of engineering physics, mianyang 62.900, {2. Department of Chemistry Nanjing University of Science and TechnologyNanjing 210094China Department of Chemistry Yancheng Teacher''s CollegeYancheng 224002China Institute of chemical materials China Academy of Engineering PhysicsMianyang 621900

Five polymer bonded explosives(PBXs)with the base explosive epsilon-CL-2.(hexanitrohexaazaisowurtzi-tane),the most important high energy density compound(HEDC),and five polymer binders(Estane 5703.GAP,HTPB,PEG,and F_(2.0}4))were *** dynamics(MD)method was employed to investigate their binding energies(E_(bind))2./PEG 2./ Estane5703.≈ epsilon-CL-2./GAP 2./HTPB 2./F_(2.0}4).By pair correlation function g(r)analyses,hydrogen bonds and vdw are found to be the main interactions between the two *** elasticity and isotropy of PBXs based epsilon-CL-2. can be obviously improved more than pure epsilon-CL-2. *** is not by changing the molecular structures of epsilon-CL-2. for each binder to affect the *** safety and energetic properties of these PBXs are mainly influenced by the thermal capability(C_p^(deg))and density(p)of binders,respectively.

关键词： high energy density material (HEDM), hexanitrohexaazaisowurtzitane (CL-2.), polymer bonded explosives (PBXs), molecular dynamics (MD), compatibility, safety properties, mechanical properties, energetic properties

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Encapsulation of inorganic particles by dispersion polymerization through ultrasonic irradiation

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Science china Chemistry 2005年第6期48卷 545-552页

作者： ZHANG Kai1,2. FU Qiang1, HUANG Yuhong2.& ZHOU Dehui2.1. College of Polymer Science and engineering, Sichuan University, Chengdu 610065, china 2. Institute of Structure Mechanics, {2., {3. 62.900, china 1. College of Polymer Science and engineering Sichuan University 610065 Chengdu China 2. Institute of Structure Mechanics China Academy of Engineering Physics 621900 Mianyang China

The nano-silica/polystyrene composite particles were prepared and characterized according to the following steps. First, the nano-silica particles were pretreated with surfactants under ultrasonic field. Second, the dispersion polymerization of styrene in a water/ethanol (1/6, weight ratio) medium, with poly(N-vinyl pyrrolidone) (PVP) as stabilizer and 2.2.-azobisizobu- tyronitrile (AIBN) as initiator in the presence of nano-silica particles was initiated with N2.purging through ultrasonic irradiation by taking its advantages of multieffect, i.e. dispersion, crushing, activation, and initiation. Finally, the polymerization kinetics characteristics were studied, and the encapsulation of composite particles was investigated with optical microscope, SEM, TEM, FTIR, X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC).

关键词： composite particle, dispersion polymerization, ultrasonic irradiation.

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