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Density functional theory study on the structural and electronic properties of Ag-adsorbed (MgO)_n clusters

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Science china(physics,Mechanics & Astronomy) 2009年第5期52卷 734-741页

作者： GE GuiXian1, JING Qun1 & LUO YouHua2,3.1 Key Laboratory of Ecophysics and department of physics, {3. College, Shihezi university, Shihezi 83.003. china 2 School of Science, East china university of Science and Technology, Shanghai 20023., china 3.Institute for Theoretical physics, Henan university, Kaifeng 475004, china Key Laboratory of Ecophysics and department of physics Normal College Shihezi University Shihezi China School of Science East China University of Science and Technology Shanghai China Institute for Theoretical physics Henan University Kaifeng China

Equilibrium geometries, charge distributions, stabilities and electronic properties of the Ag-adsorbed (MgO)n (n = 1-8) clusters have been investigated by density functional theory (DFT) with generalized gradient approximation (GGA) for exchange-correlation functional. The results show that hollow site is energetically preferred for n≥4, and the incoming Ag atoms tend to cluster on the existing Ag cluster. The Mulliken populations indicate that the interaction between the Ag atom and Magnesia clusters is mainly induced by a weak atomic polarization. The adsorbed Ag atom only causes charge redistributions of the atoms near itself. The effect of the adsorbed Ag atom on the bonding natures and structural features of Magnesia clusters is minor. Furthermore, the investigations on the first energy difference, fragmentation energies and electron affinities show that the Ag(MgO)4 and Ag(MgO)6 are the most stable among studied clusters.

关键词： Ag (MgO)_n clusters geometries electronic properties

Different-Periodic Travelling Wave Solutions for Nonlinear Equations

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Communications in Theoretical physics 2004年第4期41卷 481-486页

作者： YE Li-Jun~1 LIN Ji~(1,2)1 department of physics,Zhejiang normal {3.,Jinhua 3.1004,china2 physics department,Shanghai Jiao Tong {3.,Shanghai 20003.,china department of physics Zhejiang Normal University Jinhua 321004 China physics department Shanghai Jiao Tong University Shanghai 200030 China

Using Jacobi elliptic function linear superposition approach for the(1+1)-dimensional Caudrey-Dodd-Gibbon-Sawada-Kotera(CDGSK)equation and the(2+1)-dimensional Nizhnik-Novikov-Veselov(NNV)equation,many new periodic travelling wave solutions with different periods and velocities are obtained based on the knownperiodic *** procedure is crucially dependent on a sequence of cyclic identities involving Jacobi ellipticfunctions sn(ξ,m),cn(ξ,m),and dn(ξ,m).

关键词： linear superposition nonlinear equation travelling wave solution

Decay dynamics of excited CS_2 and NH_3.investigated by femtosecond laser

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Chinese Science Bulletin 2002年第18期47卷 1523-1528页

作者： ZHANG Jianyang LIU Hongping, YING Shuhui, JIANG Bo, XU Dali, WANG Li & LOU NanquanState Key Laboratory of Molecular Reaction Dynamics, dalian Institute of Chemical physics, Chinese Academy of Sciences, dalian 11602.,{3. department of physics, liaoning State Key Laboratory of Molecular Reaction Dynamics. dalian institute of Chemical physics Chinese Academy of Sciences Dalian China department of physics Liaoning Normal University Dalian China

By using the home-made femtosecond laser system and the time-of-flight mass spectrometer, the decay dynamics of excited carbon disulfide (CS2) and ammonia (NH3. are investigated in real time by pump-probe mul-tiphoton ionization detection. The estimated lifetime constantof the NH3.A1A2 state (51±4 fs) agreed quite well with the literature report. For the first time, the decay lifetime constants of the NH3.E’1A’1, state (93.±93.fs), the CS2 a3.2 state (153.10 fs), and the CS2 Rydberg state[3.2](3.Ig) (948±23.fs) are obtained.

关键词： femtosecond lifetime pump-probe.

A computational investigation of boron-doped chromium and chromium clusters by density functional theory

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Science china(physics,Mechanics & Astronomy) 2010年第5期53卷 812-817页

作者： GE GuiXian1,JING Qun1 & LUO YouHua2,3.1 Key Laboratory of Ecophysics and department of physics,{3. College,Shihezi university,Xinjiang 83.003.china 2 School of Science,East china university of Science and Technology,Shanghai 20023.,china 3.Institute of Theoretical physics,School of physics and Information Optoelectronics,Henan university,Kaifeng 475004,china Key Laboratory of Ecophysics and department of physics Normal College Shihezi University Xinjiang China School of Science East China University of Science and Technology Shanghai China Institute of Theoretical physics School of Physics and Information Optoelectronics Henan University Kaifeng China

The geometries,stabilities and electronic properties of Crn and CrnB(n=2-9) clusters have been systematically investigated by density functional *** results suggest that the lowest energy structures for CrnB clusters can be obtained by substituting one Cr atom in Crn+1 clusters with B *** geometries of CrnB clusters are similar to that of Crn+1 clusters except for local structural *** second-order difference and fragmentation energy show Cr4,Cr6,Cr8,Cr3.,Cr5B and Cr8B cluster are the most stable among these studied *** impurity B increases the stabilities of chromium *** B is doped on the Crn clusters,cluster geometry does dominate positive role in enhancing their *** doped B atom does not change the coupling way of the Cr site in Crn clusters,but breaks the symmetry and the Cr atoms are no longer *** doped B atom increases the total magnetic moments of Crn in most cases.

关键词： Crn and CrnB clusters geometries electronic properties

Proton induced X-ray emission (PIXE) analysis of sources of porcelain body of Ru Guan and Jun Guan porcelains

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Science china(physics,Mechanics & Astronomy) 2006年第4期49卷 411-420页

作者： LI Guoxia1, ZHAO Weijuan1, LI Rongwu2, SUN Hongwei1, GUO Min1, WANG Yanfang1, LIU Hui1, ZHAO Qingyun3. SUN Xinmin3. ZHAO Wenjun3.& CHENG Huansheng4 1. Faculty of Physical Engineering, Zhengzhou university, Zhengzhou 450052, china 2. department of {3., Beijing normal university, Beijing 100875, china 3. Institute of Cultural Relic and Archaeology of Henan Province, Zhengzhou 450000, china 4. Institute of Modern {3., Fudan university, Shanghai 20043., china Faculty of Physical Engineering Zhengzhou University Zhengzhou China department of physics Beijing Normal University Beijing China Institute of Cultural Relic and Archaeology of Henan Province Zhengzhou China Institute of Modern physics Fudan University Shanghai China

3. samples of Ru Guan porcelain body and 50 samples of Jun Guan porcelain body (both kinds being in different body colors) were selected with the purpose of finding out the source of raw materials and their classification relationship so as to search for ways of non-destructive discrimination. Proton induced X-ray emission (PIXE) has been applied to these samples to determine their chemical elements. The data of seven major chemical elements collected from these samples were further studied through fuzzy cluster analysis. Results indicate that the origin of raw materials of Jun Guan porcelain body samples is comparatively more concentrated in certain places, while that of Ru Guan porcelain body samples is scattered about. The places of origin of raw materials of the majority of Ru Guan and Jun Guan porcelain body samples have something in common, but some differences still exist. It might be an important way for non-destructive discrimination among Ru Guan and Jun Guan porcelains by combining PIXE with fuzzy cluster analysis.

关键词： Ru Guan and Jun Guan porcelain, source of porcelain body, PIXE, fuzzy cluster analysis, non-destructive discrimination.

Theoretical study on the reaction mechanism of(CH_3._3.O+CO

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Science china Chemistry 2005年第1期48卷 18-24页

作者： ZHAO Hongmei1,2,3. SUN Chengke1,4, ZHANG Rongchang3. XI Hongmin3.& LI Zonghe1 1. department of Chemistry, Beijing normal university, Beijing 100875,{3. 2. The Laboratory of Molecular Reaction Dynamics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080,{3. 3. department of Chemistry, Beihua university, Jilin 13.013.{3. 4. department of Chemistry, Qujing normal university, Yunnan 655000,{3. department of Chemistry Beijing Normal University Beijing China The Laboratory of Molecular Reaction Dynamics Institute of Chemistry Chinese Academy of Sciences Beijing China department of Chemistry Beihua University Jilin China department of Chemistry Qujing Normal University Yunnan China

The reaction mechanism of (CH3.3.O with CO has been theoretically investigated using density-functional theory (DFT) calculations at B3.YP/6-3.G* level. In order to get more reliable energy values the single-point energy is evaluated at CCSD (T)/6-3.++G** level. The results show that the reaction is multi-channel and the reaction of (CH3.3.O radical with CO mostly produces (CH3.3. + CO2. The reaction could play a role in eliminating air pollution.

关键词： DFT, B3.YP, (CH3.3.O, radical.

ON MATRIX UNITARILY INVARIANT NORM CONDITION NUMBER

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Journal of Computational Mathematics 1998年第2期16卷 121-128页

作者： Dao-sheng Zheng (department of Mathematics, East china normal {3., Shanghai 200062, china) 华东师范大学数学系上海

In this paper, the unitarily invariant norm \\.\\ on C-mxn is used. We first discuss the problem under what case, a rectangular matrix A has minimum condition number K(A) = \\A\\ \\A(+)\\, where A(+) designates the Moore-Penrose inverse of A; and under what condition, a square matrix A has minimum condition number for its eigenproblem? Then we consider the second problem, i.e., optimum of K(A) = \\A\\ \\A(-1)\\(2) in error estimation.

关键词： matrix unitarily invariant norm condition number

Stationary Classical Chaos of Trapped Two-Component Bose-Einstein Condensates in 1-D Optical Lattice Potentials

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Communications in Theoretical physics 2007年第7期48卷 125-131页

作者： FANG Jian-Shu LIU Wing-Ki ZHU Shan-Hua1 Institute of physics,Hunan university of Technology,Zhuzhou 412008,china2 {3. of physics,Hunan normal university,Changsha 410081,china3.{3. of physics,university of Waterloo,Waterloo,Ontario,Canada N2L 3.1 Institute of physics Hunan University of Technology Zhuzhou 412008 China department of physics Hunan Normal University Changsha 410081 China department of physics University of Waterloo Waterloo Ontario Canada N2L 3G1

We study the nonlinear dynamics of two-component Bose-Einstein condensates in one-dimensional pe-riodic optical lattice *** stationary state perturbation solutions of the coupled two-component nonlinearSchr?dinger/Gross-Pitaevskii equations are constructed by using the direct perturbation *** analysisrevels that the perturbation solution is the chaotic one,which indicates the existence of chaos and chaotic region inparameter *** corresponding numerical calculation results agree well with the analytical *** applying thechaotic perturbation solution,we demonstrate the atomic spatial population and the energy distribution of the systemare chaotic generally.

关键词： stationary state classical chaos two-component Bose-Einstein condensates optical lattice potential

The influence of laser pulse on the photoabsorption spectra of Li atom in strong external field

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Science china(physics,Mechanics & Astronomy) 2006年第2期49卷 178-186页

作者： WANG Dehua1 & LIN Shenglu2 1. School of physics and Electronic Engineering, Yantai normal university, Yantai 264025,{3. 2. department of physics, Shandong normal university, Jinan 250014,{3. School of physics and Electronic Engineering Yantai Normal University Yantai China department of physics Shandong Normal University Jinan China

Using the time-dependent perturbation theory and the calculation formula of the single- and double-pulse absorption spectra of the atom in strong external fields, we calculate the single- and double-pulse absorption spectra of Li atom in strong magnetic field for different pulse widths. The results show that a pulse of some width can reduce the contribution of the short period closed orbits and eliminate the contribution of the long period orbits. Compared with the single-pulse absorption spectra, we found that for some phase differences, the double-pulse laser absorption spectra are strengthened; while for others, they are reduced. Therefore, we can use the pulse laser to control the oscillation of the absorption spectra and obtain the optimization object.

关键词： laser pulse closed orbit absorption spectra.