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differential cross sections of elastic electron scattering from CH4. CF4 and SF6 in the energy range l00-700eV

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Chinese Physics B 2007年第11期16卷 3339-3344页

作者：马二俊马余刚蔡翔舟方德清沈文庆田文栋 Shahghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China Changshu Institute of Technology Changshu 215500China Graduate School of Chinese Academy of Sciences Beijing 100039China

We investigate the differential cross sections （DCS） of elastic electron scattering from CH4, CF4 and SF6 at six impact energies in a range of 100 700eV by employing the independent atom model （IAM） together with the relativistic partial waves. The atom is present in an optical potential which is complex, spherically symmetric, and energy dependent. The optical potential of the atom is the sum of the direct static, dynamic polarization, local exchange and modified absorption potentials. The results obtained by using a modified absorption potential show significant improvements on the unmodified absorption potential results. The present results are generally in good agreement with experimental data available. In addition, the present results indicate that the structure of molecule manifests the observable effects on electron- molecule scattering.

关键词： differential cross sections independent atom model electron molecule scattering relativistic partial waves modified absorption potential

Polarization and exchange effects in elastic scattering of electron with atoms and ions

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Chinese Physics B 2018年第5期27卷 179-186页

作者： Zhang-Jin Chen Dan-Dan Cui Department of Physics College of Science Shantou University Guangdong 515063 China

Laser-induced electron diffraction（LIED）, in which elastic scattering of the returning electron with the parent ion takes place, has been used to extract atomic potential and image molecular structures with sub-？A precision and exposure time of a few femtoseconds. So far, the polarization and exchange effects have not been taken into account in the theoretical calculation of differential cross section（DCS） for the laser-induced rescattering processes. However, the validity of this theoretical treatment has never been verified. In this work, we investigate the polarization and exchange effects on electron impact elastic scattering with rare gas atoms and ions. It is found that, while the exchange effect generally plays a more important role than the polarization effect in the elastic scattering process, the exchange effect is less important on electron–ion collisions than on electron–atom collisions, especially for scattering in backward direction. In addition, our calculations show that, for electron–atom collisions at incident energies above 50 e V, both the polarization and exchange effects can be safely neglected, while for electron–ion collisions, both the polarization and exchange potentials do not make substantial contributions to the DCS at incident energies above 20 e V and scattering angles larger than 90？. Our investigation confirms the validity of the current LIED method.

关键词： polarization exchange elastic scattering differential cross sections

Analysis of total reaction cross sections for deuterons on 1p-shell-nuclei

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Science China(Physics,Mechanics & Astronomy) 2018年第11期61卷 30-35页

作者： YiDi Chen Yun Zhang JianLing Lou DanYang Pang YanLin Ye Wei Liu Ying Jiang Gen Li School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University School of Physics and Nuclear Energy Engineering Beijing Key Laboratory of Advanced Nuclear Materials and Physics Beihang University

This study aims to analyze the differential cross sections （DCSs） of elastic scattering and total reaction cross sections （TRCSs） of the loosely-bound deuteron projectile impinging on lp-shell nuclei, such as 9Be, 12C, and 160, at incident energies ranging between 10.6 and 171 MeV using the continuum discretized coupled channel （CDCC） method. By fitting the experimental data for the DCSs and TRCSs, energy-dependent renormalization factors for the real and imaginary parts of the nucleon-nucleus optical-model potentials deduced from the studies proposed by Koning and Delaroche （KD02） and by Watson, Singh, and Segel （WSS）, are obtained. It is found that with the WSS potential, which was obtained specifically for lp-shell nuclei, the CDCC calculations can simultaneously reproduce both the DCSs and the TRCSs. The results show that it is important to choose appropriate optical potentials to describe deuteron-induced reactions.

关键词： total reaction cross sections differential cross sections deuteron 1p-shell nuclei

Effect of Reagent Rotational Excitation on Dynamics of F+H2→HF+H

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Chinese Journal of Chemical Physics 2015年第4期28卷 -页

作者： Tian-gang Yang Long Huang Yu-run Xie Tao Wang Chun-lei Xiao Zhi-gang Sun Dong-xu Dai Key Laboratory of Materials Modification by Laser Electron and Ion Beams (Ministry of Education)School of Physics and Optoelectronic Technology Dalian University of Technology Dalian 116024ChinaState Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics Chinese Academy of Science Dalian 116023 China State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics Chinese Academy of Science Dalian 116023 China State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics Chinese Academy of Science Dalian 116023 ChinaSynergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of China Hefei 230026 ChinaDepartment of Chemical Physics University of Science and Technology of China Hefei 230026China State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics Chinese Academy of Science Dalian 116023 ChinaSynergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of China Hefei 230026 China

The dynamics of the F+H2(v=0, j=0, 1) reactions have been studied at the collision energy of 1.27 kcal/mol using a high-resolution crossed molecular beam apparatus. HF product rotational state resolved differential cross sections have been obtained at the v′=1, 2, 3 levels. The product HF(v′=2) angular distributions are predominantly backward scattered for both H2 (j=0, 1) reagents. However, the distributions of product HF(v′=2) rotational states for the F+H2(v=0, j=0) reaction are significantly different from those for the F+H2(v=0, j=1) reaction. Experimental results show that the rotational excitation of H2 produces rotationally "hotter" HF(v′=2) product. In addition, the HF(v′=3) product is more likely scattered into the forward direction when the H2reagent is populated at j=0 state, which could be attributed to a slow-down mechanism.

关键词： crossed molecular beam Rydberg tagging differential cross sections

Electron Correlation in the Final Continuum of Ionization Hydrogen by 150-eV Electron Impact

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Chinese Physics Letters 2004年第9期21卷 1737-1740页

作者：张程华臧树良五晓伟王京阳 DepartmentofPhysics LaboratoryofAtomsandRadiationLiaoningUniversityShenyang110036 ShenyangNationalLaboratoryforMaterialsScience InstituteofMetalResearchChineseAcademyofSciencesShenyang110016

Electron correlation in triple differential cross sections for ionization of atomic hydrogen by electron impact is analysed for the case of coplanar asymmetric geometry within the framework of the two-potential formulae. Based on the approximations of projectile and faster-electron plane wave, the transition matrix element is analytically expressed to be a product of two factors: the correlation factor of two electrons in the final channel and the structure-scattering factor. The contribution of both the factors to the angular distribution of the triple differential cross section is calculated. The present results are compared with the experimental data and the other theoretical calculations for the incident energy of 150eV.

关键词： Angular distribution electron correlations cross section differential cross sections ionization electron impact Continuum Correlation factor Hydrogen Treble incident energy

Rayleigh Scattering for An Electromagnetic Anisotropic Medium Sphere

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Chinese Physics Letters 2010年第5期27卷 94-97页

作者：李应乐王明军董群峰唐高峰 Box 399 Institute of Radio Wave Propagation and Scattering Xianyang Normal University Xianyang 712000

Based on the scales theory of electromagnetic waves, the analytical expression of electrical fields inside an anisotropic medium sphere is studied. differential scattering cross section and radar cross section （RCS） for an anisotropic spherical target are presented. The correctness of the obtained results is tested. The simulation results show that the scattering of an anisotropic sphere has the property of a dipole radiation under the condition of Rayleigh scattering. The larger the dielectric constant is, the stronger the dipole scattering is. Anisotropy in magnetism only has an effect on differential RCS. These results provide a theoretical base for the identification of anisotropic targets.

关键词： RAYLEIGH scattering ELECTROMAGNETIC waves ANISOTROPY ELECTRIC fields differential cross sections SIMULATION methods & models PERMITTIVITY RADIATIVE corrections

Theoretical study of stereodynamics for reaction O（3p）＋HCl

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Chinese Physics B 2010年第8期19卷 350-355页

作者：朱通扈国栋陈建中刘新国张庆刚 College of Physics and Electronics Shandong Normal University

The vector correlation between products and reagents for reaction O（3P）＋HCl→OH＋Cl is studied using a quasi- classical trajectory （QCT） method on the benchmark potential energy surface of the ground 3A″ state [Ramachandran and Peterson, J. Chem. Phys. 119 （2003） 9550]. The generalised differential cross section （2π/σ）（dσ00/dwt） is presented in the centre of mass frame. The distribution of dihedral angles, P（Фr）, and the distribution of angles between k and j′, P（θr）, are calculated. The influence of the collision energy and the influence of the reagent rotation and vibration on the product polarization are studied in the present work. The calculated results indicate that the rotational polarization of product molecule is almost independent of collision energy but sensitive to the reagent rotation and vibration. product rotational polarization, vector correlations, differential cross sections, quasi- classical trajectory

关键词： product rotational polarization vector correlations differential cross sections quasi-classical trajectory

Theoretical Study of Isotopic Effect of Oxygen Atom on the Stereodynamics for the O（^3P）＋ D2 → OD ＋ D Reaction

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Chinese Physics Letters 2010年第12期27卷 46-49页

作者：刘世莉石英 Institute of Atomic and Molecular Physics dilin University Changchun 130012

Quasi-classical trajectory theory is used to study the isotope effect of oxygen atoms on the vector correlations in the O（^3P）＋ D reaction at a collision energy of 25kcal/mol using accurate potential energy surface of the 3A＇ triplet state. The distributions of p（θr） and the distribution of dihedral angel p（φr） as well as p（θr,φr） are calculated. Moreover, four polarization-dependent generalized differential cross sections （PDDCSs） of product are presented in the center-of-mass frame. The results indicate that the polarization of the product presents different characters for the isotope effect of oxygen atoms. Isotopic substitute can cause obviously different effects on the four PDDCSs.

关键词： OXYGEN isotopes REACTION mechanisms (Chemistry) POTENTIAL energy surfaces differential cross sections VECTOR analysis ATOMS

State-to-state dynamics of reactions H+DH'(v=0,j=0)→HH'(v',j')+D/HD(v',j')+H'with time-dependent quantum wave packet method

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Chinese Physics B 2021年第7期30卷 192-199页

作者： Juan Zhao Da-Guang Yue Lu-Lu Zhang Shang Gao Zhong-Bo Liu Qing-Tian Meng School of Science Shandong Jiaotong UniversityJinan 250357China School of Physics and Electronics Shandong Normal UniversityJinan 250358China

State-to-state time-dependent quantum dynamics calculations have been carried out to study H+DH'→HH'+D/HD+H'reactions on BKMP2 *** total integral cross sections of both reactions are in good agreement with earlier theoretical and experimental results,moreover the rotational state-resolved reaction cross sections of H+DH'→HH‘+D at collision energy Ec=0.5 eV are closer to the experimental values than the ones calculated by Chao et al[***.1178341(2002)],which proves the higher precision of the quantum calculation in this *** addition,the state-to-state dynamics of H+DH'→HD'+H reaction channel have been discussed in detail,and the differences of the micro-mechanism of the two reaction channels have been revealed and analyzed clearly.

关键词： state-to-state time-dependent quantum wave-packet method differential cross sections