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Influence of Early-staged Energy Barrier on stereodynamics of Reaction of LiH(v=0, j=0)＋H → Li ＋ H2

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Chemical Research in Chinese Universities 2013年第5期29卷 956-961页

作者： SHA Guang-yan YUAN Jiu-chuang MENG Chang-gong CHEN Mao-du Experimental Center of Chemistry School of Chemistry School of Physics and Optoelectronic Technology College of Advanced Science and Technology Dalian University of Technology Dalian 116024 P. R. China

Theoretical studies of stereodynamics for reaction LiH（v=0, j=0）＋H → Li＋H2 have been carried out with quasiclassical trajectory method on two potential energy surfaces（PESs） structured as W-PES and P-PES. The main difference of the two PESs is at fixed angle of Li--H--H from 110° to 180°. In this angle range, there is an early- staged energy barrier on the P-PES, but there is no barrier on the W-PES. Some studies have been done to explore the influence of the early-staged energy barrier on this exothermic reaction. Integral cross sections, differential cross sec- tions and product rotational angular momentum of the reaction have been calculated. When Ec〈0.48 eV, the do- minant influence of barrier is to restrain reacting. However, when Ec〉0.48 eV, the dominant influence of barrier is to promote reacting. The angular distribution of the product H2 is extremely forward on both the PESs, because the life- time of most complexes is short. Totally, the lifetime on the P-PES is longer than that on W-PES for the existence of the barrier. With the collision energy increasing, on the both PESs, the distribution of the direction of the product H2 angular momentum changed, and there is a trend that peak at （90°,270°） gets weaker and peak at （90°,90°） gets stronger. The energy barrier weakens the degree of the rotation alignment of the H2.

关键词： stereodynamics Quasiclassical trajectory method Product rotational polarization

Theoretical study of stereodynamics for the D'+ DS(v=0,j=0) → D'D + S abstraction reaction

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Chinese Physics B 2013年第5期22卷 279-284页

作者：郭雅慧张凤昀马红章 College of Science China University of Petroleum

Quasiclassical trajectory （QCT） calculations have been performed for the abstraction reaction, Dt＋ DS（v = 0, j = 0） → D＇D ＋ S on a new LZHH potential energy surface （PES） of the adiabatic 3A＇＇ electronic state [Lü et al. 2012 J. Chem. Phys. 136 094308]. The collision energy effect on the integral cross section and product polarization are studied over a wide collision energy range from 0.1 to 2.0 eV. The cross sections calculated by the QCT procedure are in good accordance with previous quantum wave packet results. The three angular distribution functions, P（θr）, P（φr）, and P（θr,φr）, together with the four commonly used polarization-dependent differential cross sections （（2 π/σ）（ d σ00 / d ω1）, （2π/σ）（d σ20 / d ω1）, （2π/σ）（dσ22＋/dω1）, （2π/σ）（dσ21-/dω1）） are obtained to gain insight into the chemical stereodynamics of the title reaction. Influences of the collision energy on the product polarization are exhibited and discussed.

关键词： quasi-classical trajectory integral cross section stereodynamics product polarization

The collision energy effect on the stereodynamics of the Ca + HCl→CaCl + H reaction

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Chinese Physics B 2013年第4期22卷 222-226页

作者：王立志杨传路梁景娟段莉莉张庆刚 College of Physics and Electronics Shandong Normal University School of Physics and Optoelectronic Engineering Ludong University

The stereodynamics of the reaction of Ca ＋ HCl are calculated at three different collision energies based on the potential energy surface [Verbockhaven G et al. 2005 J. Chem. Phys. 122 204307] using quasi-classical trajectory theory. The polarization-dependent differential cross sections （PDDCSs）（2π/σ ）（dσ 00 /dω t ）, （2π/σ ）（dσ 20 /dωt ）, （2π/σ ）（dσ 22＋ /dωt ）, （2π/σ ）（dσ 21 /dω t ） and the distributions of P（θ r ）, P（φr ）, and P（θr ,φr ） are calculated. The results indicate that the rotational polarization of the CaCl product presents different characteristics for the different collision energies, and the effects of the collision energy on the vector potential, including the alignment, orientation, and PDDCSs, are not obvious.

关键词： stereodynamics quasi-classical trajectory vector correlation collision energies effect

stereodynamics study of reactions N（2D）＋HD→NH＋D and ND＋H

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Chinese Physics B 2010年第4期19卷 223-228页

作者：岳现房程杰李宏张永强 Emilia L.Wu Department of Physics and Information Engineering Jining University Department of Chemical Engineering and Materials Science 421 Washington Avenue SEMinneapolisMinnesota 55455USA

The product polarizations of the title reactions are investigated by employing the quasi-classical trajectory （QCT） method. The four generalized polarization-dependent differential cross-sections （PDDCSs）（2π/σ）（dσ00/dωt）, （2π/σ）（dσ20/dωt）, （2π/σ）（dσ22＋/dωt）, and （2π/σ）（dσ21-/dωt） are calculated in the centre-of-mass frame. The distribution of the angle between κ and j＇, P（θr）, the distribution of the dihedral angle denoting κ-κ＇-j＇ correlation, P（Фr）, as well as the angular distribution of product rotational vectors in the form of polar plots P（θr, Фr） are calculated. The isotope effect is also revealed and primarily attributed to the difference in mass factor between the two title reactions.

关键词： stereodynamics quasi-classical trajectory method vector correlation polarization-dependent differential cross-section isotope effect

Energy and rotation-dependent stereodynamics of H(~2S) + NH(a^1?) → H_2(X^1Σ_g^+) + N(~2D) reaction

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Chinese Physics B 2016年第2期25卷 135-142页

作者：李永庆杨云帆于洋张永嘉马凤才 Department of Physics Liaoning University State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical PhysicsChinese Academy of Sciences

Quasi-classical trajectory calculations are performed to study the stereodynamics of the H（~2S）＋ NH（a^1？） →H_2（X^1Σ_g~＋）＋ N（~2D） reaction based on the first excited state NH_2（1~2A＇） potential energy surface reported by Li et al.[Li Y Q and Varandas A J C 2010 J. Phys. Chem. A 114 9644] for the first time. We observe the changes of differential cross-sections at different collision energies and different initial reagent rotational excitations. The influence of collision energy on the k-k＇ distribution can be attributed to a purely impulsive effect. Initial reagent rotational excitation transforms the reaction mechanism from insertion to abstraction. The effect of initial reagent rotational excitations on k-k＇ distribution can be explained by the rotational excitation enlarging the rotational rate of reagent NH in the entrance channel to reduce the probability of collision between incidence H atom and H atom of target molecular. We also investigate the changes of vector correlations and find that the rotational angular momentum vector j＇ of the product H_2 is not only aligned, but also oriented along the y axis. The alignment parameter, the disposal of total angular momentum and the reaction mechanism are all analyzed carefully to explain the polarization behavior of the product rotational angular moment.

关键词： differential cross section stereodynamics rotational excitation rotational polarization Vector cor- relation

Isotopic Effects on stereodynamics for Ca＋HCI, Ca＋DCI, and Ca＋TCl Reactions

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Chinese Journal of Chemical Physics 2011年第6期24卷 686-690,I0003页

作者：王立志杨传路梁景娟肖静张庆刚山东师范大学物理与电子科学学院济南250014 鲁东大学物理学院烟台264025

The vector correlations in Ca＋HCl, Ca＋DCl, and Ca＋TCl reactions have been investigated by means of the quasi-classical trajectory calculations on PES constructed by means of multireference configuration interaction. The distributions of P（θr）, P（Фr） and the PDDCSs of （2π/σ）（dσ00/dωt）, （2π/σ）（dσ20/dωt）, （2π/σ）（dσ22＋/dωt）, （2π/σ）（dσ21-/dωt） have been calculated based on the surface. The remarkable isotopic effects in the reactions are observed, and the mechanism which may be ascribed to different mass factors is discussed.

关键词： Isotopic effect stereodynamics Quasi-classical trajectory Vector correlation

Theoretical Study on stereodynamics of Reactions of N（^2D）＋H2→NH＋H and N（^2D）＋D2→ND＋D

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Chinese Journal of Chemical Physics 2010年第4期23卷 381-386,I0001页

作者：岳现房程杰冯海冉李宏 Emilia L. Wu 济宁学院物理与信息工程系曲埠273155 明尼苏达大学化工与材料科学系明尼阿波利斯55455

The vector correlations between products and reagents for the title reactions have been calculated by the quasi-classical trajectory method at a collision energy of 21.32 kJ/mol on an accurate potential energy surface of Ho et al. （J. Chem. Phys. 119, 3063 （2003））. The peaks of the product angular distribution are found to be in both backward and forward directions for the two title reactions. The product rotational angular momentum is not only aligned, but also oriented along the negative direction of y-axis. These theoretical results are in good agreement with recent experimental findings for the two title reactions. The isotopic effect is also revealed and primarily attributed to the difference of the mass factor in the two title reactions.

关键词： stereodynamics Quasi-classical trajectory method Vector correlation Polarization-dependent differential cross-section Isotopic effect

Theoretical study of stereodynamics for the O（3P）＋ H2 → OH ＋ H reaction

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Chinese Physics B 2011年第1期20卷 333-338页

作者：刘世莉石英 Institute of Atomic and Molecular Physics Jilin University

This paper employs the quasi-classical trajectory calculations to study the influence of collision energy on the title reaction on the potential energy surface of the ground 3A1 triplet state developed by Rogers et al. （J. Phys. Chem. A 2000 104 2308）. It calculates the product angular distribution of P（θr）, P（Фr） and P（θr, Фr） which reflects vector correlation. The distribution P（Фr） shows that product rotational angular momentum vectors ：j＇ of the products are strongly aligned along the relative velocity direction k. The distribution of P（Фr） implies a preference for left-handed product rotation in planes parallel to the scattering plane. Four different polaxisation-dependent cross-sections are also presented in the centre-of-mass frame. Results indicate that OH is sensitively affected by collision energies of H2.

关键词： quasi-classical trajectory polarisation-dependent generalised differential cross-sections stereodynamics

Influence of Vibrational Excitation on stereodynamics for O（3P）＋D2→OD＋D Reaction

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Chinese Journal of Chemical Physics 2010年第6期23卷 649-654,745页

作者：刘世莉石英吉林大学原子与分子物理研究所吉林130012

Theoretical investigations on the stereodynamics of the O（3P）＋D2 reaction have been calculated by means of the quasi-classical trajectory to study the product rotational polarization at collision energy of 104.5 k J/tool on the potential energy surface of the ground 3A＂ triplet state. The vector properties including angular momentum alignment distributions and four polarization dependent generalized differential cross-sections of product have been presented. Furthermore, the influence of reagent vibrational excitation on the product vector properties has also been studied. The results indicate that the vector properties are sensitively affected by reagent vibrational excitation.

关键词： Vector correlation Quasi-classical trajectory Polarization dependent generalized differential cross-section stereodynamics