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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, normal College, Shihezi {3., Shihezi 83.003. china 2.School of Science, East china {3. of Science and Technology, Shanghai 2.02.0}, china 3.Institute for Theoretical physics, Henan {3., 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

A phenomenological equation of state for isospin asymmetric nuclear matter

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Science china(physics,Mechanics & Astronomy) 2009年第10期52卷 1494-1505页

作者： CHEN LieWen1,2.1 Department of physics,Shanghai Jiao Tong university,Shanghai 2.02.0,{2. 2.Center of Theoretical {3. physics,National Laboratory of Heavy Ion Accelerator,Lanzhou 73.000,{2. Department of physics Shanghai Jiao Tong University Shanghai China Center of Theoretical nuclear physics National Laboratory of Heavy Ion Accelerator Lanzhou China

A phenomenological momentum-independent(MID) model is constructed to describe the equation of state(EOS) for isospin asymmetric nuclear matter,especially the density dependence of the nuclear symmetry {2. Esym(ρ).This model can reasonably describe the general properties of the EOS for symmetric nuclear matter and the symmetry {2. predicted by both the sophisticated isospin and momentum dependent MDI model and the Skyrme-Hartree-Fock *** find that there exists a nicely linear correlation between Ksym and L as well as between J0/K0 and K0,where L and Ksym represent,respectively,the slope and curvature parameters of the symmetry {2. at the normal nuclear density ρ0,while K0 and J0 are,respectively,the incompressibility and the third-order derivative parameter of symmetric nuclear matter at ρ*** correlations together with the empirical constraints on K0,L and Esym(ρ0) lead to an estimation of -477 MeV Ksat,2.-2.1 MeV for the second-order isospin asymmetry expansion coefficient for the incompressibility of asymmetric nuclear matter at the saturation point.

关键词： equation of state of nuclear matter isospin the symmetry energy

Zircon and apatite fission track analyses on mineralization ages and tectonic activities of Tuwu-Yandong porphyry copper deposit in northern Xinjiang, china

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Science china Earth Sciences 2007年第12期50卷 1787-1795页

作者： YUAN WanMing1,BAO ZengKuan2.DONG JinQuan2.GUO ZhaoJie3.& DENG Jun1 1 State Key Laboratory of Geological Processes and Mineral Resources,china {2. of Geosciences,Beijing100083.china 2.Laboratory of {3. Analysis Techniques,Institute of High energy physics,Chinese Academy of Sciences,Beijing 10003.,china 3.Department of Geology,Peking {2.,Beijing 100871,china State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing China Laboratory of nuclear Analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing China Department of Geology Peking University Beijing China

The mineralization ages reported in the past in the Tuwu-Yandong copper district not only are different,but also fall into the Hercynian *** study has achieved 9 zircon and 7 apatite fission track analysis *** zircon fission track ages range from 158 Ma to 2.9 Ma and the apatite ages are between 64 Ma and 140 *** mineralization accords with the regional tectonics in the copper *** consider that the zircon fission track age could reveal the mineralization age based on annealing zone temperature of 140―3.0℃ and retention temperature of ～2.0℃ for zircon fission track,and metallogenetic temperature of 12.―3.0℃ in this ore *** three mineralization epochs have been identified,i.e.,2.9―2.6 Ma,2.0}―2.0 Ma and 165―158 Ma,and indicate occurrence of the min-eralization in the Indosinian and Yanshan *** to apatite fission track ages,the three tectonic-mineralizing epochs are 140―13. Ma,109―97 Ma and 64 Ma,which means age at about 100℃ after the *** three epochs lasted 146 Ma,108 Ma and about 100 Ma from ～2.0℃ to ～100℃ and trend decrease from early to *** is shown by the fission track modeling that this district underwent three stages of geological thermal histories,stable in Cretaceous and cooling both before Cretaceous and after 2. Ma.

关键词： mineralization age, tectonic epoch, fission track, zircon, apatite, Tuwu-Yandong, Xinjiang

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,normal College,Shihezi {3.,Xinjiang 83.003.china 2.School of Science,East china {3. of Science and Technology,Shanghai 2.02.0},china 3.Institute of Theoretical physics,School of physics and Information Optoelectronics,Henan {3.,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

Experimental and theoretical study of^(13.C shielding tensors in new-style molybdenum complex

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Science china Chemistry 2004年第3期47卷 214-221页

作者： HOU Guangjin1,2. WANG Liying2. LU Xiaoming3. ZHENG Anmin2. DENG Feng2.&YE Chaohui1,2.1. Department of physics, Huazhong {2. of Science and Technology, Wuhan 43.074, china 2. State Key Laboratory of Magnetic Resonance and Atomic and Molecular physics, Wuhan Institute of physics and Mathematics, Chi-nese Academy of Sciences, Wuhan 43.071, china 3. Department of Chemistry, Capital normal {2., Beijing 10003., china Department of physics Huazhong University of Science and Technology Wuhan China Chinese Academy of Sciences Wuhan China Department of Chemistry Capital Normal University Beijing China

13. 2.-PASS spectra of two new cis-dioxo catecholatomolybdenum complexes (NH2.H2.H2.HCH2.2.H+)3.MovO 2.C6H4O2.2. and (NH2.H2.H2.H2.H2.2.H+)3.Mo(v)O2.(C2.2.2.2. have been obtained by solid-state nuclear magnetic resonance (NMR), in which the spinning sidebands were well-separated. The principal components of the 13. shielding tensors were extracted by theoretically fitting the intensities of 13. spinning sidebands. The effects of counter cations on 13. chemical shift isotropy and shielding tensor of cis-dioxo catecholatomolybdenum complex anion [Mo (v)O2.C6H4O2.2.3. were studied, comparing the 13. CSA of those carbon sites in complex anions with that of the counter cations. Based on the known structure of the molybdenum complex crystal, theoretical values of 13. shielding tensors were calculated by the ainitio GIAO method, in comparison with the experimental results.

关键词： NMR, magic angle spinning, chemical shift anisotropy, shielding tensor, cis-dioxo-monomolybdenum.

Time of impact of fragment P2.of comet SL 9 on Jupiter

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Chinese Science Bulletin 1997年第5期42卷 396-398页

作者： ZHOU Hongnan,QIAN Bochen, HUANG Keliang and LI Qibin1. Department of Astronomy, Nanjing university, Nanjing 2.0093.{2. 2. Shanghai Observatory, Chinese Academy of Sciences, Shanghai 2.003.,{2. 3. {3. Department, Nanjing normal university, Nanjing 2.0097,{2. 4. Beijing Astronomical Observatory, Chinese Academy of Sciences, Beijing 100080,{2. Department of Astronomy Nanjing University Nanjing China Shanghai Observatory Chinese Academy of Sciences Shanghai China physics Department Nanjing Normal University Nanjing China Beijing Astronomical Observatory Chinese Academy of Sciences Behijing China

FROM 1994-07-16 to 1994-07-2., 2. fragments of comet SL 9 impacted against Jupiter in succession. During the impact period the impact of fragments D, E, K, N, P2.and S was observed in china. We used a 1.56-m telescope with the CCD camera of Shanghai Observatory to monitor Jupiter and its Galilean Satellites, obtaining 1000 high-quality images at B, V, I wave bands. Our data on optical wave bands are rather complete and valuable in the world. Specially, we got some images of Jupiter, Io and Europa in the impact time of fragment P2.impacting against Jupiter. This will help us understand the precise time, position, depth and energy of the P2.s collision. In this note, we report the impact time of fragment P2.of comet SL 9 and Jupiter. Since the impact of comet SL 9 was expected to take place on the side of Jupiter

关键词： comet comet Shoemaker-Levy 9 impacting against Jupiter impact time.

Heavy ion reactions around the Coulomb barrier

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中国科学：物理学、力学、天文学英文版 2011年第S1期54卷 6-13页

作者： ZHANG HuanQiao1, LIN ChengJian1, JIA HuiMing1, ZHANG ChunLei1,2. ZHANG GaoLong1,3. YANG Feng1, LIU ZuHua1, AN GuangPeng1, WU ZhenDong1, XU XinXing1 & JIA Fei1 1 china Institute of Atomic {2., P. O. Box 2.5(10), Beijing 102.13. china 2.Particle Astro{3. Center, Institute of High {2. {3., Chinese Academy of Sciences, Beijing 10003., china 3.School of {3. and {12. {2. Engineering, Beihang university, Beijing 100191, china china Institute of Atomic energy Beijing China Particle Astrophysics Center Institute of High Energy Physics Chinese Academy of Sciences Beijing China School of physics and nuclear {2. Engineering Beihang University Beijing China

The angular distributions of fission fragments for the 3.S+184W reaction near Coulomb barrier energies are measured. The ex perimental fission excitation function is obtained. The measured fission cross sections are decomposed into fusion-fission, quasi-fission and fast fission contributions by the dinuclear system (DNS) model. The hindrance to completing fusion both at small and large collision energies is explained. The fusion excitation functions of 3.S+90,96Zr in an energy range from above to below the Coulomb barrier are measured and analyzed within a semi-classical model. The obvious effect of positive Q-value multi-neutron transfers on the sub-barrier fusion enhancement is observed in the 3.S+96Zr system. In addition, the excitation functions of quasi-elastic scattering at a backward angle have been measured with high precision for the systems of 16O+2.8Pb, 196Pt, 184W, and 154,152.m at energies well below the Coulomb barrier. Considering the deformed coupling effects, the extracted diffuseness parameters are close to the values extracted from the systematic analysis of elastic and inelastic scattering data. The elastic scattering angular distribution of 17F+12. at 60 MeV is measured and calculated by using the continuum-discretized coupled-channels (CDCC) approach. It is found that the diffuseness parameter of the real part of core-target potential has to be increased by 2.% to reproduce the experimental result, which corresponds to an increment of potential depth at the surface re gion. The breakup cross section and the coupling between breakup and elastic scattering are small.

关键词： fusion-fission quasi-fission fusion hindrance fusion enhancement surface diffuseness parameter exotic nuclei

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 412.08,{2.2.Department of physics,Hunan normal university,Changsha 410081,{2.3.Department of physics,university of Waterloo,Waterloo,Ontario,Canada N2. 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

Further research on high-spin structure in ^(161)Lu

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Science china(physics,Mechanics & Astronomy) 2008年第3期51卷 315-320页

作者： LI YanXia1,2.YU ShaoYing1,2.4,SHEN CaiWan1,5,LI XiaoWei6 & CHEN YongShou3.4 1 School of Science,Huzhou Teachers College,Huzhou 3.3.00,china 2.College of Mathematics,physics and Information Engineering,Zhejiang normal {3.,Jinhua 3.1000,china 3.5} Institute of Atomic energy,Beijing 102.13.china 4 Institute of Theoretical physics,Chinese Academy of Sciences,Beijing 100080,china 5 Center of Theoretical nuclear physics,National Laboratory of Heavy Ion Accelerator of Lanzhou,Lanzhou 73.000,china 6 Department of physics,Chifeng {3.,Chifeng 02.001,china School of Science Huzhou Teachers College Huzhou China College of Mathematics Physics and Information Engineering Zhejiang Normal University Jinhua China Institute of Theoretical physics Chinese Academy of Sciences Beijing China Center of Theoretical nuclear physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou China Department of physics Chifeng University Chifeng China china Institute of Atomic energy Beijing China

The two-dimensional total routhian surface (TRS) calculations were performed to probe into the triaxial superdeformed characteristics of a strongly populated band X2.in 161Lu. This band was identified as a triaxial superdeformed band by using our TRS method. We also got its formation mechanics,i.e. the neutron-shell correction energy plays a crucial role,while the rotating energy and the deformation-driving effect of high j intruder orbit i1{2.2.also play an additional role.

关键词： TRS method triaxial superdeformation formation mechanism