共查询到20条相似文献,搜索用时 31 毫秒
1.
Isotope effect on the stereodynamics for the collision reaction H+LiF(v = 0, j = 0) → HF+Li 下载免费PDF全文
Stereodynamics for the reaction H+LiF(v=0, j=0) → HF+Li and its isotopic variants on the ground-state (1 2 A′) potential energy surface (PES) are studied by employing the quasi-classical trajectory (QCT) method. At a collision energy of 1.0 eV, product rotational angular momentum distributions P (θr), P (φr), and P (θr ,φr), are calculated in the center-of-mass (CM) frame. The results demonstrate that the product rotational angular momentum j′ is not only aligned along the direction perpendicular to the reagent relative velocity vector k, but also oriented along the negative y axis. The four generalized polarization-dependent differential cross sections (PDDCSs) are also computed. The PDDCS 00 distribution shows a preferential forward scattering for the product angular distribution in each of the three isotopic reactions, which indicates that the title collision reaction is a direct reaction mechanism. The isotope effect on the stereodynamics is revealed and discussed in detail. 相似文献
2.
<正>The quasi-classical trajectory(QCT) method based on the extended London-Eyring-Polanyi-Sato potential energy surface is used to investigate the product vibrational distribution,angular distribution and angle-resolved kinetic distribution of the reaction Ba+C3H7Br→BaBr+C3H7 at 2.58 kcal/mol.The calculated results show that the product BaBr vibrational distribution is quite hot,the vibrational population peaks are located at v = 12,and the angular product distribution tends to backward scattering.The calculated angle-resolved kinetic distribution shows that the kinetic distribution is obviously related to angle.The QCT results are always qualitatively acceptable and sometimes even quantitatively. 相似文献
3.
The effect of collision energy on the stereodynamics of the reaction H(~2S)+NH(X~3∑~-,v = 0,j = 0)→ N(~4S)+H_2 下载免费PDF全文
The quasi-classical trajectory(QCT) is calculated to study the stereodynamics properties of the title reaction H(2S)+NH(X3∑-) →N(4S)+H2 on the ground state 4A' potential energy surface(PES) constructed by Zhai and Han [2011 J.Chem.Phys.135 104314].The calculated QCT reaction probabilities and cross sections are in good agreement with the previous theoretical results.The effects of the collision energy on the k-k' distribution and the product polarization of H2 are studied in detail.It is found that the scattering direction of the product is strongly dependent on the collision energy.With the increase in the collision energy,the scattering directions of the products change from backward scattering to forward scattering.The distribution of P(θr) is strongly dependent on the collision energy below the lower collision energy(about 11.53 kcal/mol).In addition,the P(φr) distribution dramatically changes as the collision energy increases.The calculated QCT results indicate that the collision energy plays an important role in determining the stereodynamics of the title reaction. 相似文献
4.
Stereodynamics of the He + D2^+ → HeD^+ + D Reaction on the PALMIERI Surface 总被引:1,自引:0,他引:1 下载免费PDF全文
Using the quasi-classical trajectory method, the product rotational polarization of the ion-molecule reaction He^+D2^+ has been calculated at different collision energies on the PALMIERI potential energy surface [Palmieri et al. Mol. Phys. 98 (2000) 1835]. The distribution angle between k and j′, P(Or), the distribution of the dihedral angle P(Фr), and the angular distribution of product rotational vectors in the form of polar plots in θr and Фr are calculated. In addition, four polarization-dependent differential cross sections are also presented in the center-of-mass frame, respectively. The results indicate that the rotational polarization of the product HeD^+ presents different characters for different collision energies. These discrepancies may be ascribed to the different collision energies and constructions of the potential energy surface. 相似文献
5.
Quasi-classical trajectory study of collision energy effect on the stereodynamics of H + Br O → O + HBr reaction 下载免费PDF全文
Quasi-classical trajectory(QCT) studies on the stereodynamics of H + Br O → O + HBr reaction have been performed on the X1A′state of ab initio potential energy surface by Peterson [Peterson K A 2000 J. Chem. Phys. 113 4598] in a collision energy range from 0 kcal/mol to 6 kcal/mol. Two of the polarization-dependent generalized differential cross sections(PDDCSs),(2π /σ)( dσ00/ dωt)(PDDCS00) and(2π /σ)( dσ20/ dωt)(PDDCS20) are considered. The rotational polarizations of these products show sensitive behaviors to the calculated collision energy range. Furthermore, in order to gain more knowledge about vector correlations, the product angular distribution, P(θr), and the dihedral angle, P(φr),are calculated, and the results indicate that both the rotational alignment and orientation of the product are enhanced as collision energy increases. 相似文献
6.
Study of the H+HS reaction on a newly built potential energy surface using the quasi-classical trajectory method 下载免费PDF全文
<正>The quasi-classical trajectory(QCT) method is used to study the H+HS reaction on a newly built potential energy surface(PES) of the triplet state of H2S(3A″) in a collision energy range of 0-60 kcal/mol.Both scalar properties, such as the reaction probability and the integral cross section(ICS),and the vector properties,such as the angular distribution between the relative velocity vector of the reactant and that of the product,etc.,are investigated using the QCT method.It is found that the ICSs obtained by the QCT method and the quantum mechanical(QM) method accord well with each other.In addition,the distribution for the product vibrational states is cold,while that for the product rotational states is hot for both reaction channels in the whole energy range studied here. 相似文献
7.
Theoretical prediction of energy dependence for D+BrO→DBr+O reaction:The rate constant and product rotational polarization 下载免费PDF全文
A quasi-classical trajectory(QCT) calculation is used to investigate the vector and scalar properties of the D + Br O → DBr + O reaction based on an ab initio potential energy surface(X1A state) with collision energy ranging from 0.1 kcal/mol to 6 kcal/mol. The reaction probability, the cross section, and the rate constant are studied. The probability and the cross section show decreasing behaviors as the collision energy increases. The distribution of the rate constant indicates that the reaction favorably occurs in a relatively low-temperature region(T 100 K). Meanwhile, three product angular distributions P(θr), P(φr), and P(θr, φr) are presented, which reflect the positive effect on the rotational angular momentum j' polarization of the DBr product molecule. In addition, two of the polarization-dependent generalized differential cross sections(PDDCSs), PDDCS00 and PDDCS20, are computed as well. Our results demonstrate that both vector and scalar properties have strong energy dependence. 相似文献
8.
In order to explore the isotope effect on stereo dynamics, we investigate the trajectory calculations of Ar+H2+/D2+/T2+ and Ar+T2+ reactions on the ab initio potential energy surface constructed by us and calculate the distributions of product polarization P(θr), P(r) and four generalized polarization-dependent differential cross-sections. The product rotational alignment parameters (P2(j' · k)) for the title reactions are compared and discussed with mass factors. Furthermore, the angular distributions of the product rotational vectors in the form of polar plot in θr and r are presented. The results indicate that the stereo dynamics properties of the title reactions are sensitive to the mass factor. 相似文献
9.
Quasi-classical trajectory study of the isotope effect on the stereodynamics in the reaction H(2S) + CH(X2∏; v=o,j= 1)→ C(1D)+H2(X1∑g+) 下载免费PDF全文
The isotope effect on the stereodynamic properties in the title reaction is investigated by a quasi-classical trajectory (QCT) method on the 11At potential energy surface at a collision energy of 23.06 kcal/mol. The angular distributions P(φr ), P(θr), P(θr, φr), and the polarization-dependent generalized differential cross sections are calculated, which demonstrate the observable influences on the rotational polarization of the product by the isotopic substitution of H with D. 相似文献
10.
Energy and rotation-dependent stereodynamics of H(~2S) + NH(a~1?) → H_2(X~1Σ_g~+) + N(~2D) reaction 下载免费PDF全文
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. 相似文献
11.
A theoretical study of the stereodynamics for reaction O(1D) + CH4→OH + CH3 has been carried out using the quasiclassical trajectory method(QCT) on a potential energy surface structured by Gonzalez et al. The integral cross sections(ICSs), differential cross sections(DCSs) and product rotational angular momentum polarization have been calculated. With the collision energy increasing, the ICS decreases. There is no threshold energy, because no barrier is found on the minimum energy path. The DCS results show that the backward and forward scatterings exist at the same time. With the collision energy increasing, the dominant rotation of the product changes from the right-handed direction to the left-handed direction in planes parallel to the scattering plane. In the isotopic effect study, the decrease of the mass factor weakens the polarization degree of the rotational angular momentum vectors of the products. 相似文献
12.
<正>The quasi-classical trajectory(QCT) method is used to calculate the stereo-dynamics of the exchange reaction H_a+LiH_b→LiH_a+H_b and its isotopic variants based on an accurate potential energy surface reported by Prudente et al.[Prudente F V,Marques J M C and Maniero A M 2009 Chem.Phys.Lett.474 18].The reactive probability of the title reaction is computed.The vector correlations and four polarization-dependent generalized differential cross sections(PDDCSs) at different collision energies are presented.The influences of the collision energy and the reagent rotation on the product polarization are studied in the present work.The results indicate that the product rotational angular momentum j’ is not only aligned,but also oriented along the direction perpendicular to the scattering plane. The product polarization distributions of the title reaction and its isotopic variants exhibit distinct differences which may arise from different mass combinations. 相似文献
13.
Quasi-classical trajectory approach to the O(1D)+HBr )OH+Br reaction stereo-dynamics on X1A' potential energy surface 下载免费PDF全文
The vector properties of reaction O(1D)+HBr→ OH+Br on the potential energy surface (PES) of X1A′ ground singlet state are studied by using the quasi-classical trajectory (QCT) theory. The polarization-dependent differential cross sections (PDDCSs), the average rotational alignment factor 2(j′· k)>, as well as the distributions reflecting vector correlations are also computed. The analysis of the results shows that the alignment and the orientation distribution of the rotation angular momentum vector of product molecule OH is influenced by both the effect of heavy-light-heavy (HLH) type mass combination and the deep well of PES. 相似文献
14.
We investigate the influence of reagent vibration on the stereodynamics of the title reaction by the quasi-classical trajectory on the Aguado-Paniagua2-potential energy surface developed by Aguado et al. (J. Chem. Phys. 1997 106 1013). The cross sections and reaction probability as functions of the reagent vibration are calculated in the centre-of-mass frame. The product angular distributions of p(θr), p(φr), and p(θr, φr), which reflect the vector correlation, are also presented and discussed. The results indicate that the vector properties are sensitively affected by the vibrational excitation. 相似文献
15.
This paper studies the influence of the reagent vibration
on the reaction O(1D)+HF → HO+F by using a quasi-classical
trajectory method on the new \textitab initio 1A' ground
singlet potential energy surface (Gómez-Carrasco et al
2007 Chem. Phys. Lett. 435 188--193). The product
angular distributions which reflect the vector correlation are
calculated. Four polarization-dependent differential cross sections
(PDDCSs) which are sensitive to many photoinitiated bimolecular
reaction experiments are presented in the center of the mass frame,
respectively. The differential cross section indicates that the OH
product mainly tends to the forward scattering, and other PDDCSs are
also influenced by the vibration levels of HF. 相似文献
16.
Theoretical study of stereodynamics for the D'+ DS(v=0,j=0) → D'D + S abstraction reaction 下载免费PDF全文
Quasiclassical trajectory (QCT) calculations have been performed for the abstraction reaction, D'+ DS(v = 0, j = 0) → D'D + S on a new LZHH potential energy surface (PES) of the adiabatic 3 A 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 ((2π/σ)(dσ00/dωt), (2π/σ)(dσ20/dωt), (2π/σ)(dσ22+/dωt), (2π/σ)(dσ21/dωt)) 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. 相似文献
17.
Quasi-classical trajectory study of the isotope effect on the stereodynamics in the reaction H(2S) + CH(X2Π;u= 0,j= 1) → C(1D) + H2(X1Σg+) 下载免费PDF全文
The isotope effect on the stereodynamic properties in the title reaction is investigated by a quasi-classical trajectory(QCT) method on the 11A potential energy surface at a collision energy of 23.06 kcal/mol. The angular distributions P(θr),P(φr), P(θr, φr), and the polarization-dependent generalized differential cross sections are calculated, which demonstrate the observable influences on the rotational polarization of the product by the isotopic substitution of H with D. 相似文献
18.
<正>The vector correlation between products and reagents for reaction O(~3P)+HCl→OH+Cl is studied using a quasiclassical 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)(dσ_(00)/dω_t) is presented in the centre of mass frame.The distribution of dihedral angles,P(φr),and the distribution of angles between k and j', P(θ_r),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 the product molecule is almost independent of collision energy but sensitive to the reagent rotation and vibration. 相似文献
19.
The stereodynamics and reaction mechanism of the H′(^2S) + NH (X^3∑^-) → N(^4S) + H2 reaction are thoroughly studied at collision energies in the 0.1 eV-1.0 eV range using the quasiclassical trajectory (QCT) on the ground 4A″ potential energy surface (PES). The distributions of vector correlations between products and reagents P(φr), P(φr) and P(φr,φr) are presented and discussed. The results indicate that product rotational angular momentum j′ is not only aligned, but also oriented along the direction perpendicular to the scattering plane; further, the product H2 presents different rotational polarization behaviors for different collision energies. Furthermore, four polarization-dependent differential cross sections (PDDCSs) of the product He are also calculated at different collision energies. The reaction mechanism is analyzed based on the stereodynamics properties. It is found that the abstraction mechanism is appropriate for the title reaction. 相似文献
20.
《中国物理 B》2019,(2)
The quantum state-to-state calculations of the D + ND→N + D_2 reaction are performed on a potential energy surface of 4 A' state. The state-resolved integral and differential cross sections and product state distributions are calculated and discussed. It is found that the rotational distribution, rather than the vibrational distribution, of the product has an obvious inversion. Due to the fact that it is a small-impact-parameter collision, its product D_2 is mainly dominated by rebound mechanism, which can lead to backward scattering at low collision energy. As the collision energy increases, the forward scattering and sideward scattering begin to appear. In addition, the backward collision is also found to happen at high collision energy, through which we can know that both the rebound mechanism and stripping mechanism exist at high collision energy. 相似文献