共查询到19条相似文献,搜索用时 74 毫秒
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运用准经典轨线法结合Peterson从头计算势能面,在碰撞能分别为20.9,41.80和66.88 kJ/mol时,对放热反应O(1D)+HBr(v=0,j=0)→OH+Br(△H=-252.89 kJ/m01)进行了细致的立体动力学性质研究.反映k与j'两矢量相关的函数P(θr)的分布表明产物分子的转动角动量j'在垂直于反应物相对速度矢量k的方向上有强烈的取向分布,且随碰撞能的变化比较明显;反映k,k'与j'三矢量相关的函数P(φr)的分布表明产物转动角动量j'不仅有沿着y轴的取向效应,还有沿着y轴正向的弱定向效应,且这种弱定向效应随碰撞能的增加有所减弱;描述产物转动角动量j'的空间分布函数P(θr,φr)在(90°,90°)和(90°,270°)两处有两个明显的分布,随着碰撞能的增加,这两个集中分布越来越密集,碰撞能对该分布有一定的影响.产物分子的极化主要集中在垂直于散射面的平面内.除此之外,极化微分反应截面(PDDCSs)给出了反应产物的散射方向. 相似文献
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基于Aguado等人拟合的APW势能面(PES),运用准经典轨线(QCT)方法,对反应Li+HF(v=0,j=0)→LiF+H的动力学性质进行了计算.主要研究了不同碰撞能条件下的反应截面、转动取向、产物散射角分布和竞争反应模式等.结果表明,该反应存在直接提取型和间接插入型两种反应模式,在低能量下反应以间接插入反应模式为主,能量大于200 meV时则以直接提取反应为主. 相似文献
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基于Aguado等人拟合的APW势能面(PES), 运用准经典轨线(QCT)方法, 对反应Li+HF(ν=0, j=0)→LiF+H的动力学性质进行了计算. 主要研究了不同碰撞能条件下的反应截面、转动取向、产物散射角分布和竞争反应模式等. 结果表明, 该反应存在直接提取型和间接插入型两种反应模式, 在低能量下反应以间接插入反应模式为主, 能量大于200 meV时则以直接提取反应为主. 相似文献
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在扩展Lond-Eyring-Polanyi-Sato(LEPS)势能面上,采用准经典轨线方法对反应Ca+CD3I→CaI+CD3进行了动力学计算,并讨论了该反应的同位素效应.在同位素效应作用下,产物CaI的振动态分布向低振动态转移,反应体系的散射截面在低碰撞能和高碰撞能处有较小的变化.同时,受到反应物的质量因子变化的影响,产物转动取向值减少,产物转动取向增强.仅有产物的角分布受同位素效应的影响不明显. 相似文献
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用准经典轨线方法在Aguado-Paniagua2(AP2)势能面上计算了反应物转动量子态对H+LiF→HF+Li反应立体动力学的影响. 给出了关于产物和反应物之间矢量相关的P(μr)和P(ár)的分布情况. 同时计算了四个极化微分反应截面. 结果表明转动量子态对H+LiF→HF+Li反应的矢量性质有很大影响. 还计算了H+LiF→HF+Li反应的反应几率. 相似文献
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运用准经典轨线方法,基于Peterson从头计算势能面对O+HCl→OH+Cl反应的立体动力学性质进行了研究.讨论了在31.77和51.04 kJ/mol两种碰撞能情况下极化依赖的微分反应截面(2π/σ)(dσ00/dωt),(2π/σ)(dσ20/dωt),(2π/σ)(dσ22+/dωt)和(2π/σ)(dσ21-/dωt)以及描述k-j′两矢量相关和k-k′-j′三矢量相关的分布函数P(θr)和P(фr).计算得到的P(θr)分布表明,产物分子的转动角动量j′具有强烈的取向分布,并且产物转动角动量的取向效应对散射能的变化比较敏感.而P(фr)的分布表明,产物分子虽然具有沿着y轴的取向效应,但是没有明显的定向效应. 相似文献
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The quasiclassical trajectory method is used to study the vector correlations of the reactions Ca+RBr (R=CH3, C2H5 and n-C3H7Br) and the rotational alignment of product CaBr. The product rotational alignment parameters at di?erent collision energies and the vector correlations between the reagent and product are numerically calculated. The vector correlations are described by using the angle distribution functions P(θr),P(φr), P(θr, φr) and the polarization-dependent differential cross sections (PDDCSs). The peak values of P(θr) of the product CaBr from Ca+CH3Br are larger than those from Ca+C2H5Br and Ca+n-C3H7Br. The peak of P(θr) atφr = 3π/2 is apparently stronger than that at φr= π/2 for the three reactions Ca+RBr. The calculation results show that the rotational angular momentum of the product CaBr is not only aligned, but also oriented along the direction which is perpendicular to the scattering plane.The product CaBr molecules are strongly scattered forward. The orientation and alignment of the product angular momentum will affect the scattering direction of the product molecules to varying degrees. 相似文献
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基于PPA势能面(Palmieri,P.;Puzzarini,C.;Aquilanti,V.Mol.Phys.,2000,98:1835),运用准经典轨线(quasi—classical trajectory)方法,对反应He+H2^+(v=0—2,j=0)→HeH^++H的立体动力学性质进行了理论研究.结果表明,反应物振动激发对反应的k-j’两矢量相关和k—k’-j’三矢量相关分布都产生了较大影响.除此之外,极化微分反应截面对振动量子数”也非常敏感. 相似文献
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The Ca+CH3I→CaI+CH3 reaction system has been studied with the quasi-classical trajectory method on the extended Lond-Eyring-Polanyi-Sato(LEPS) potential energy surface. At collision energy Ecol=10.78 kJ/mol, the calculated results show that the CaI vibrational population peaks are located at v=2. The calculated cross section decreases slowly with the collision energy increasing. The angle product distributions tend toward backward scattering. The calculated (P2(J^1·K)) values deviate slightly from-0.5 and decrease with increasing collision energy. The Quasiclassical trajectory calculation(QCT) results are in reasonable agreement with experimental data. Moreover, the dynamics of the reaction has been discussed. 相似文献
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H+CN体系中平行络合反应的动力学 总被引:1,自引:0,他引:1
利用分子反应动力学的经典轨迹法研究化学反应体系已经开展了很多工作,但是,研究长寿命络合物的几何异构体就显得有些困难,主要表现在该方法对几何异构体不容易判别.由于这些原因和计算机时大增,Davis[1]利用经典轨迹法和统计方法相结合,研究了H+CN和H+NC体系在固定方位时的长寿命络合物动力学行为,并且采用Murrel等[2]拟合光谱数据的势能函数,该势能函数在HCN和HNC平衡点的频率与实验值相差较大.本文利用经典轨迹法研究了H+CN产生HCN和HNC平行络合物异构体的分子反应动力学行为,揭示了平行络合反应产生几何异构体的… 相似文献
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Mode Specificity Dynamics of Prototypical Multi-Channel H+CH3OH Reaction on Globally Accurate Potential Energy Surface 下载免费PDF全文
The H+CH\begin{document}$ _3 $\end{document} OH reaction, which plays an important role in combustion and the interstellar medium, presents a prototypical system with multiple channels. In this work, mode specific dynamics of different product channels is investigated theoretically on a recently developed reliable potential energy surface based on a large number of data points calculated at the level of UCCSD(T)-F12a/AVTZ. It has been demonstrated that vibrational excitations of the O\begin{document}$ - $\end{document} H stretching motion, the torsional motion, the C\begin{document}$ - $\end{document} H stretching vibrations, show different influences on the four product channels, H\begin{document}$ _2 $\end{document} +CH\begin{document}$ _3 $\end{document} O, H\begin{document}$ _2 $\end{document} +CH\begin{document}$ _2 $\end{document} OH, H\begin{document}$ _2 $\end{document} O+CH\begin{document}$ _3 $\end{document} , and H+CH\begin{document}$ _3 $\end{document} OH. This work is helpful for understanding the mode-specific dynamics and controlling the competition for complicated reactions with multiple product channels. 相似文献
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运用准经典轨线方法, 基于Peterson从头计算势能面对O+HCl→OH+Cl反应的立体动力学性质进行了研究. 讨论了在31.77和51.04 kJ/mol两种碰撞能情况下极化依赖的微分反应截面(2π/σ)(dσ00/dωt), (2π/σ)(dσ20/dωt), (2π/σ)(dσ22+/dωt)和(2π/σ)(dσ21-/dωt)以及描述k-j′两矢量相关和k-k′-j′三矢量相关的分布函数P(θr)和P(φr). 计算得到的P(θr)分布表明, 产物分子的转动角动量j′具有强烈的取向分布, 并且产物转动角动量的取向效应对散射能的变化比较敏感. 而P(φr)的分布表明, 产物分子虽然具有沿着y轴的取向效应, 但是没有明显的定向效应. 相似文献
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Quasi-Classical Trajectory Investigation of H+SO$ _{2} \rightarrow $OH+SO Reaction on Full-Dimensional Accurate Potential Energy Surface 下载免费PDF全文
The reaction H+SO\begin{document}$ _2 $\end{document} \begin{document}$ \rightarrow $\end{document} OH+SO is important in the combustion and atmospheric chemistry, as well as the interstellar medium. It also represents a typical complex-forming reaction with deep complexes, serving as an ideal candidate for testing various kinetics theories and providing interesting reaction dynamical phenomena. In this work, we reported a quasi-classical trajectory study of this reaction on our previously developed accurate full-dimensional potential energy surface. The experimental thermal rate coefficients over the temperature range 1400 K\begin{document}$ \leq $\end{document} \begin{document}$ T $\end{document} \begin{document}$ \leq $\end{document} 2200 K were well reproduced. For the reactant SO\begin{document}$ _2 $\end{document} being sampled at the ground ro-vibrational state, the calculated integral cross sections increased slightly along the collision energy ranging from 31.0 kcal/mol to 40.0 kcal/mol, and then became essentially flat at the collision energy within 40.0\begin{document}$ - $\end{document} 55.0 kcal/mol. The product angular distributions are almost symmetric with nearly identical backward-forward double peak structure. The products OH and SO vibrational state distributions were also analyzed. 相似文献
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基于PuH_2分子基态(X~7A_1)的分析势能函数,用准经典的Monte-Carlo轨线法 对Pu(~7Fg)+H_2(X~1∑_g~+,0,0)的分子反应动力学过程进行了计算。结果表明 :Pu(~7F_g)与H_2(X~1∑_g~+,0,0)碰撞是弹性碰撞。 相似文献
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利用光纤光谱仪构建微量反应系统,并通过偶氮染料橙黄II在铁-亚硫酸钠-溶解氧体系中的脱色反应,分别用特征动力学方程法及初始速率法进行了脱色反应动力学分析。该实验体系能够实现简单、快速的均相溶液反应动力学实验,其数据处理方法较好地巩固和提升了对反应动力学理论课教学内容的学习。整个实验体系的设计与应用能够满足物理化学、大学化学、环境化学等相关课程中有关反应动力学的实验教学需求。 相似文献
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根据反应速率的碰撞理论及反应独立共存原理,对包括振荡反应在内的均相化学反应的计算机模拟进行了探讨,在系统讨论有关Moote-Carlo模拟问题中,着重论述了模拟中分支反应与有效碰撞数的关系及计算机时间与实际反应时间的换算问题。提出了通用于各种均相化学反应的模拟算法,并成功地用于化学振荡反应机理的探讨。 相似文献
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