摘要
在过去的几十年里,分子反应动力学研究已经取得了很大进展,并已经深入到态-态反应过程。对原子分子碰撞反应,实验和理论研究以前总是主要关注反应的一些标量性质。近年来,随着实验技术的迅速发展,化学反应的矢量性质,比如速度和角动量等,引起了人们广泛的兴趣。因为只有把标量性质和矢量性质综合起来考虑,才能呈现完整的动力学信息。准经典轨线(QCT)计算就是研究原子与分子碰撞的立体反应动力学的一种有效方法。
本文主要基于Persky等构造的最新的London-Eyring-Polanyi-Sato(LEPS)势能面,采用QCT方法研究了H+BrF→HBr+F反应。计算了反映矢量相关的角分布和在光诱导的双分子反应实验中比较敏感的四个极化微分截面。结果表明:随着碰撞能的增加,产物的转动极化变强,并且产物分子的后向散射占主导地位。通过比较反应D+BrF→DBr+F和H+BrF→HBr+F的产物极化,揭示了明显的同位素效应。本文也采用相同的方法研究了反应物的振动态对O(1D)+HF→F(1P) +OH反应的影响,发现产物分子主要表现为后向散射。由于反应物振动态的不同,极化微分截面(PDDCSs)呈现不同的特点。
论文共分为五章。第一章为简要地介绍了分子反应动力学及立体动力学的发展和研究现状,第二章介绍了QCT的原理、计算方法以及势能面的知识。第三章对H+BrF→HBr+F反应的理论研究结果进行了分析和讨论,揭示了碰撞能和同位素对立体反应动力学的影响。第四章介绍了反应物的振动态对O(1D)+HF→F(1P) +OH反应的影响,并做了讨论。第五章是结束语,对本论文的所有内容进行了总结。
During the past decades, molecular reaction dynamics has made great progress and has gotten into a new stage of the state-to-state chemical dynamics. Formerly, the theoretical and experimental study of the atomic and molecular collision reaction always focused on some scalar properties. With the rapid development of experimental techniques, however, the interest in vector properties of chemical reactions, such as velocities and angular momentum, has increased significantly in recent decades. Only by understanding the scalar and vector properties together, can we obtain the fullest picture of the scattering dynamics. Quasiclassical Trajectory Calculation (QCT) is one of the effective methods for investigating atomic and molecular collision reaction stereodynamics.
QCT calculations are carried out for the exothermic reaction H+BrF→HBr+F on the latest London-Eyring-Polanyi-Sato (LEPS) potential energy surface. The product angular distributions which reflect the vector correlation are calculated; Polarization dependent differential cross sections which are sensitive to many photoinitiated bimolecular reaction experiments are presented in the center of mass frame. The calculated results suggest that the poduct rotational polarization becomes stronger as collision energy increases and products were mainly backward scattering. By comparing the poduct polarization of reactions D+BrF→DBr+F and H+BrF→HBr+F, the isotope effects have also been revealed. Using the same mothod, we study the stereodynamics of the reaction O(1D)+HF→F(1P) +OH, and analyze the influence of the reagent vibration on the stereodynamics of this reaction. The results indicate that the OH product mainly tends to the forward scattering, and polarization dependent differential cross sections (PDDCSs) are also influenced by the vibration levels of HF.
The paper can be divides into five chapters. The outline of the molecular reaction dynamics and stereodynamics is presented in the introduction. The QCT principle, the computational method, and the knowledge of potential energy surface is given in the second chapter. The QCT results of the reaction H+BrF→HBr+F are presented in the third section. The paper also calculates the effect of the reagent vibration on stereodynamics of the reaction O(1D)+HF→F(1P) +OH, which can be found in the fourth section. The fifth chapter is the conclusion, which makes a summary about content involved the in this article.
引文
[1]何国钟,分子反应动力学如何走向21世纪,化学进展1994,6,255-265.
[2] Liu X, Lin J J, Harich S A, Schatz G C, X. Yang, A quantum state-resolved insertion reaction: O('D)+H2(j=0)→OH+H(2S), Science.2000, 289,1536.
[3] Brooks P. R., Reactions of oriented molecules: Molecules can be oriented in molecular beams and their reactions show some unexpected steric effects, Science. 1976, 193,11-16.
[4] Yuh H J and Dagdigian P J, Spin-orbit effects in chemical reactions: The reaction of spin-orbit state-selected Ca(3P0J) with CI2, Br2, and CH3CL, J. Chem. Phys. 1984, 81, 2375-2480.
[5] Menzinger M, Electronic Chemiluminescence in Gases, Advance in Chemical Physics, 1980, Vol.XLII.
[6] Prisant M G., Rettner C T, Zare R N, Dependence of product alignment on product vibration for the Ca+FZ chemiluminescent, Chem. Phys.Lett. 1982, 88, 271-274.
[7] Karplus M, Porter P N, Sharma R D, Exchange Reaction with Activaton Energy I.Simple Barrier Potential for (H,H2), J.Chem.Phys. 1965, 43, 3259-3287.
[8] Doll J, Semiclassical theory of atom-solid surface collisions:Elastic scattering, Chem. Phys.1974, 3, 257-264.
[9] Miller W H, Dynamics of Molicular Collisions Part B, New York, Plenum Press,1976.
[10] Wall F T, Hiller L A, Mazur J. Statistical Computation of Reaction Probabilities, J. Chem. Phys.1961, 35, 1284-1289.
[11] Bunker D L, Monte Carlo Calculations.Further Studies of Unimolecular Dissociation, J. Chem. Phys.1964, 40, 1946-1957.
[12] Muckerman J T, Classical dynamics of the reaction of fluorine atome with hydyogen molecules. III. Hot-atom reaction of F with HD, J. Chem. Phys.1972, 57, 3388-3396.
[13] Fano U, Macek J H, Impact excitation and polarization of the emitted light, Rev. Mod. Phys. 1973, 45, 553-573.
[14] Case D A, Herschbach D R, Statistical theory of angular momentum polarization in chemical reactions, Mol. Phys. 1975, 30, 1537-1545.
[15] Blais N C, Truhlar D G, Monte carlo trajectories: alignment of HBr rotational angular momentum as a function of scattering angle for the reaction H+Br2→HBr+Br, J. Chem. Phys.1977, 67, 1540-1546.
[16] Noda C, Zare R N, Dynamics of kinematically constrained bimolecular reactions having constant product recoil energy, J. Chem. Phys. 1987, 86, 3968-3977.
[17] Hartree W S, Simons J P, Gonzalez-Urena A, Angular disposal and rotational alignment in kinematically constrained reactions, J. Chem. Soc. Faraday Trans, 1990, 86, 17-20.
[18]韩克利,何国钟,楼南泉,瞬时碰撞反应模型.化学物理学报,1989,2,323-332.
[19]李润君,韩克利,李芙警等,用瞬时碰撞模型处理化学反应产物的转动取向,化学物理学报1993,6,1-5.
[20] Safron S A, Weinstein N D, Herschbach D R et al, Transition State Theory for Collision Complexes:Product Translational Energy Distribution, Chem.Phys.Lett. 1972,12,564-568.第二章
[21] Kuppermann A, Schatz G C, Quantum mechanical reactive scattering: An accurate three dimensional calculation, J. Chem. Phys. 1975, 62, 2502-2504.
[22] Kuppermann A, G C Schatz, Quantum mechanical reactive scattering for three-dimensional atom plus diatom systems.II.Accurate cross sections for H+H2, J. Chem. Phys. 1976, 65, 4668-4692.
[23] Pack R T, Coordinates for an optimum CS approximation in reactive scattering, Chem.Phys.Lett. 1984, 108, 333-338.
[24] Kuppermann A, Kaye J A, Dwyer J P, Hyperspherical coordinates in quantum mechanical collinear reactive scattering, Chem.Phys.Lett.1980, 74,257-262.
[25] Manolopoulos D E, An improved log derivative method for inelastic scattering, J. Chem. Phys. 1986, 85, 6425-6429.
[26] Zhang J Z H, Miller W H, Accurate three一dimensional quantum scattering calculations for F+H2 to HF+H, J. Chem. Phys. 1988, 88, 4549-4550.
[27] Zhang J Z H, Miller W H, New method for quantum reactive scattering, with applications to the 3-D H+H2 reaction, Chem.Phys.Lett. 1980, 74, 329-337.
[28] Manolopoulos D E, Wyatt R E, Quantum scattering via the log derivative version of the Kohn variational principle, Chem.Phys.Lett.1988, 152, 23-32.
[29] Wagner W A, A classical statistical theory for chemical reactions, J. Chem. Phys. 1976, 65, 4343-4354.
[30] Wolken G, Theoretical studies of atom-solid elastic scattering: He+LiF, J. Chem. Phys. 1973, 58, 3047-3064.
[31] Schatz G C, Kuppermann A, Quantum mechanical reactive scattering for three-dimensional atom plus diatom systems.II.Accurate cross sections for H+H2, J. Chem. Phys. 1976, 65, 4668-4679.
[32] Redmon M J, Wyatt R E, Concentration quenching of pyrene in the vapour phase, Chem.Phys.Lett.1979, 63, 209-214.
[33] McNutt J F, Wyatt R E, Redmon M J, Quantum dynamics of the three-dimensional F+H2 reaction.I.Energy partitioning and entropy analysis in the collision complex, J. Chem. Phys. 1984, 81, 692-712.
[34] Huston J M, Schartz C, Selective adsorption resonances in the scattering of helium atoms from xenon coated graphite: Close-coupling calculations and potential dependence, J. Chem. Phys. 1983,79, 5179-5189.
[35] Yu C, Whaley K B, Hogg C S, Sibener S,Selective adsorption resonances in the scattering of n-H2 p-H2 n-D2 and o-D2 from Ag(111), Phys.Rev.Lett.1983, 51, 2210-2213.
[36] Masel R I, Merril R P, Miller W H, A semiclassical model for atomicscattering from solid surfaces-He and Ne scattering from W(112) J. Chem. Phys. 1976, 64, 45-56.
[37] Pack R J, Coordinates for an optimum CS approximation in reactive scattering, Chem. Phys.Lett. 1984, 108, 333-338.
[38] Kuppermann A, Kay J A, Hyperspherical coordinates in quantum mechanical collinear reactive scattering, Chem. Phys.Lett. 1980, 74, 257-262.
[39] Miller W H, Jansen op de Hanr B M D, A new basis set method for quantum scattering Calculations, J. Chem. Phys. 1987, 86, 6213-6220.第三章
[40] Polanyi J C, Skrlac W J, Energy distribution among reaction products X.H+ICl→HCl+I,H+ClBr→HCI+Br,HBr+Cl, Chem. Phys. 1977, 23, 167-194.
[41] Bykhalo I B, Filatov V V, Gordon E B, Perminov A P, Kinetics study of two-channel hydrogen and deuterium atom reactions with interhalogen molecules Russ. Chem. Bull. 1994, 43, 1637-1645.
[42] Last I, Baer M, Three-dimensional DIM-3C potential energy surfaces for the reactions H+XY and X+HY (X,Y=F, Cl, Br, I), J. Chem. Phys. 1984, 80, 3246-3252.
[43] Sayós R, Hernando J, Francia R, González M, Quasiclassical trajectory study of the H+ ClF→F+ HCl, Cl+ HF and F+ HCl→Cl+ HF reactions and their deuterium isotope variants on a new (2Ao) ab initio potential energy surface, Phys. Chem. Chem. Phys. 2000, 2, 523-534.
[44] Kornweitz H, Persky A, Quasiclassical Trajectory Calculations for the Reactions F + HCl, F + HBr, and F + HI, J. Phys. Chem. A 2004, 108, 140-145.
[45]薛卫东、朱正和、冉鸣、王红艳、邹乐西、孙颖,U+ CO体系的分子反应动力学研究,物理学报2002,51,2503-2508
[46]沈光先、汪荣凯、令狐荣锋、杨向东,不同能量的氦原子与同位素分子H2 (D2, T2)碰撞分波截面的理论计算,物理学报2008,57,155-159.
[47]汪荣凯、沈光先、宋晓书、令狐荣锋、杨向东, He同位素对He-NO碰撞体系微分截面的影响,物理学报2008,57,4138-4142.
[48] Kim S K, Herschbach D R, Angular momentum disposal in atom exchange reactions, Faraday Discuss.Chem. Soc. 1987, 84, 159-169.
[49] Kim H L, Wickramaaratchi M A, Zheng X , Hall G E, Reactions of velocity-aligned atoms probed by Doppler profiles: H+O2 OH+O, J. Chem. Phys. 1994, 101, 2033-2050.
[50] Han K L, He G Z, Lou N Q, Effect of location of energy barrier on the product alignment of reaction A+BC, J. Chem. Phys. 1996, 105, 8699-8704.
[51] Zhao J, Xu Y, Meng Q T, Influence of collision energy on the axial polarization of product molecule for reaction F+HO→HF+O, Cana. J. Phys. (已接受)
[52] Miranda M P de, Clary D C, Quantum dynamical stereochemistry of atom–diatom reactions, J. Chem. Phys. 1997, 106, 4509-4521.
[53] Brouard M, Gatenby S D, Joseph D M, Vallance C, The H + N2O OH(2, ,N ) + N2 reaction: OH rotational angular momentum polarization, J. Chem. Phys. 2000, 113, 3162.
[54] Orr-Ewing A J, Zare R N, Orientation and alignment of reaction products, Annu. Rev. Phys. Chem. 1994, 45, 315-366.
[55] Zhang X, Han K L, High-order symplectic integration in quasi-classical trajectory simulation: Case study for O(1D) + H2, Int. J. Quantum Chem. 2006, 106, 1815-1819.
[56] Chen M D, Han K L, Lou N Q, Vector correlation in the H+D2 reaction and its isotopic variants: isotope effect on stereodynamics, Chem. Phys. Lett. 2002, 357, 483-490.
[57] Meng Q T, Zhao J, Xu Y, Yue D G, Theoretical study of the stereo-dynamics of the reaction H+FO→OH+F, Chem. Phys. 2009, 362, 65-70.
[58] Xu Y, Zhao J, Yue D G, Liu H, Zheng X Y, Meng Q T, Effect of the reagent vibration on stereo-dynamics of the reaction O(1D)+HF→F +OH, Chin. Phys.B 2009, 18, 5308-5312.
[59] Zhao J, Xu Y, Yue D G, Meng Q T, Quasi-classical trajectory study of thereaction H+FO→OH+F, Chem. Phys. Lett. 2009, 471,160-163.
[60] Zhao J, Xu Y, Meng Q T, Isotope effect of the stereo-dynamics for the reactions F+HO→HF+O and F+DO→DF+O, J. Phys.B 2009, 42,165006.
[61] Zhang C H, Zhang W Q, Chen M D, Theoretical Studies of stereodynamics for the H+ + H2 (ν= 0–3, j = 0)→H2 + H+ reaction, J. Theor. Comput. Chem. 2009, 8, 403-415.
[62] Zhang W Q, Cong S L, Zhang C H, Xu X S, Chen M D, Theoretical Study of Dynamics for the Abstraction Reaction H′+ HBr(v=0, j=0)→H′H + Br?, J. Phys. Chem. A 2009, 113, 4192-4197.
[63] Li W L, Wang M S, Yang C , Liu W, Sun C, Ren T, Theoretical study of the stereodynamics of the reactions of D- + H2→H- + HD and H- + D2→D- + HD, Chem. Phys. 2007, 337, 93-98.第四章
[64] Sorokin V I, Gritsan N P and Chichinin A I, Collisions of O(1D) with HF, F2, XeF2, NF3, and CF4: Deactivation and reaction, J.Chem.Phys.1998, 108, 8995-9003.
[65] Gómez-Carrasco S, Hernández M L and Alvarino J M, Quantum and quasiclassical state-selected O(1D) + HF reaction dynamics and kinetics on a new MRCI ground singlet potential energy surface, Chem. Phys.Lett. 2007, 435,188-193.
[66] Liu X G, Zhang Q G, Zhang Y C, Wang M L and Zhang John Z H, Time-dependent quantum dynamics study for reaction of D+CH4 right arrow CH3+HD, Chin. Phys. 2004, 13,1013-1017.
[67]许燕,赵娟,王军,刘芳,孟庆田,碰撞能和同位素取代对H+BrF→HBr+F反应立体动力学影响的理论研究,物理学报2010,6
[68] Liu Y F, Zhu Z L, Sun J F, Cong S L and Han K L, Electron scattering from molecule CH4 at 10-5000eV, Chin.phys. 2003, 12, 750-752.
[69] Chu T S, Zhang Y and Han K L, The time-dependent quantum wave packet approach to the electronically nonadiabatic processes in chemical reactions,Int. Rev.Phys.Chem. 2006, 25, 201-235.
[70] Chu T S, Han K L, Coriolis coupling effects in small chemical reactions, Phys. Chem. Chem. Phys. 2008, 10, 2431-2443.