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Chen H, Mao Y, Yang Z, Chen M. A Neural Network Potential Energy Surface and Quantum Dynamics Study of Ca( 1S) + H 2( v 0 = 0, j 0 = 0) → CaH + H Reaction. ACS OMEGA 2024; 9:30804-30812. [PMID: 39035896 PMCID: PMC11256353 DOI: 10.1021/acsomega.4c03465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Revised: 06/12/2024] [Accepted: 06/18/2024] [Indexed: 07/23/2024]
Abstract
The reactive collision between Ca and H2 molecules has attracted great interest experimentally due to the key role of the product CaH molecule in the field of astrophysics and cold molecules. However, quantum dynamics calculations for this system have not been reported due to the lack of a global potential energy surface (PES). Herein, a globally accurate PES of the ground-state CaH2 is developed by combining 11365 high-level ab initio points and permutation invariant polynomial neural network method. Based on the newly constructed PES, the state-to-state quantum dynamics calculations for the Ca(1S) + H2 (v 0 = 0, j 0 = 0) → CaH + H reaction are carried out using the time-dependent wave packet method. The dynamic results reveal that the reaction follows the complex-forming mechanism near the reactive threshold, whereas both the indirect insertion mechanism and direct abstraction mechanism have effects at higher collision energies. The newly constructed PES can be used to further study the influence of isotope substitution, rovibrational excitation, and spatial orientation of reactant molecules on reaction dynamics.
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Affiliation(s)
- Hanghang Chen
- Key
Laboratory of Materials Modification by Laser, Electron, and Ion Beams
(Ministry of Education), School of Physics, Dalian University of Technology, Dalian 116024, China
| | - Ye Mao
- Key
Laboratory of Materials Modification by Laser, Electron, and Ion Beams
(Ministry of Education), School of Physics, Dalian University of Technology, Dalian 116024, China
| | - Zijiang Yang
- School
of Physics and Electronic Technology, Liaoning
Normal University, Dalian 116029, China
| | - Maodu Chen
- Key
Laboratory of Materials Modification by Laser, Electron, and Ion Beams
(Ministry of Education), School of Physics, Dalian University of Technology, Dalian 116024, China
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Bai M, Lu D, Li Y, Li J. Ring-polymer molecular dynamical calculations for the F + HCl → HF + Cl reaction on the ground 1 2A' potential energy surface. Phys Chem Chem Phys 2016; 18:32031-32041. [PMID: 27407007 DOI: 10.1039/c6cp03306g] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2023]
Abstract
The reaction kinetics of the heavy-light-heavy abstraction reaction F + HCl → HF + Cl on the ground electronic state potential energy surface (PES) is investigated theoretically by a recently developed ring polymer molecular dynamics (RPMD) approach. First, a new PES is developed by the permutation invariant polynomial neural network (PIP-NN) approach based on 30 620 points sampled over a large configuration space from the latest and most accurate Deskevich-Hayes-Takahashi-Skodje-Nesbitt (DHTSN) PES (J. Chem. Phys., 2006, 124, 224303). Excellent fitting performance was achieved with only 521 parameters. The PIP-NN PES is 11 times faster than the DHTSN PES. Besides, the first analytical derivatives with respect to the coordinates of the atoms have been obtained for the PIP-NN PES. The RPMD rate coefficients on the PIP-NN PES are calculated and compared with available theoretical and experimental results. It is found that the experimental rate coefficients are significantly larger than the theoretical results on the DHTSN PES, due to its overestimated reaction barrier. We conclude that a reliable PES for this important heavy-light-heavy reaction is highly desirable.
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Affiliation(s)
- Mengna Bai
- School of Chemistry and Chemical Engineering, Chongqing University, Chongqing 401331, China.
| | - Dandan Lu
- School of Chemistry and Chemical Engineering, Chongqing University, Chongqing 401331, China.
| | - Yongle Li
- Department of Physics, International Center of Quantum and Molecular Structure, and Shanghai Key Laboratory of High Temperature Superconductors, Shanghai University, Shanghai 200444, China.
| | - Jun Li
- School of Chemistry and Chemical Engineering, Chongqing University, Chongqing 401331, China.
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Freixas-Lemus VM, Martínez-Mesa A, Uranga-Piña L. Quasi-Classical Trajectory Study of Atom-Diatomic Molecule Collisions in Symmetric Hyperspherical Coordinates: The F + HCl Reaction as a Test Case. J Phys Chem A 2016; 120:2059-69. [PMID: 27002240 DOI: 10.1021/acs.jpca.5b11525] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We investigate the reactive dynamics of the triatomic system F + HCl → HF + Cl for total angular momentum equal zero and for different low-lying rovibrational states of the diatomic molecule. For each of the initial vibrational quantum numbers, the time evolution of the atom-diatom collision process is investigated for a wide range of impact angles and collision energies. To this purpose, the Quasi-Classical Trajectories (QCT) method was implemented in a hyperspherical configuration space. The Hamilton equations of motion are solved numerically in an intermediate effective Cartesian space to exploit the relative simplicity of this intermediate representation. Interatomic interactions are described by a London-Eyring-Polanyi-Sato potential energy surface, specifically developed for the title reaction, and the results of the QCT simulations are discussed in terms of the time-evolution of the hyperangles. The analysis of the collision dynamics using symmetric hyperspherical coordinates provides, in addition to the description in terms of a natural reaction coordinate (the hyperradius), a more striking representation of the exchange dynamics, in terms of the time-dependent probability distribution along the kinematic rotation hyperangle, and a precise distinction between direct and indirect mechanisms of the reaction.
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Affiliation(s)
- Victor Manuel Freixas-Lemus
- DynAMoS (Dynamical processes in Atomic and Molecular Systems), Facultad de Física, Universidad de la Habana , San Lázaro y L, La Habana 10400, Cuba
| | - Aliezer Martínez-Mesa
- DynAMoS (Dynamical processes in Atomic and Molecular Systems), Facultad de Física, Universidad de la Habana , San Lázaro y L, La Habana 10400, Cuba
| | - Llinersy Uranga-Piña
- DynAMoS (Dynamical processes in Atomic and Molecular Systems), Facultad de Física, Universidad de la Habana , San Lázaro y L, La Habana 10400, Cuba
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Aoto YA, Köhn A. Revisiting the F + HCl → HF + Cl reaction using a multireference coupled-cluster method. Phys Chem Chem Phys 2016; 18:30241-30253. [DOI: 10.1039/c6cp05782a] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A potential energy surface for the title reaction is constructed using a multireference coupled-cluster method, giving rate constant in excellent agreement with experiments.
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Affiliation(s)
- Yuri Alexandre Aoto
- Institut für Theoretische Chemie
- Universität Stuttgart
- D-70569 Stuttgart
- Germany
| | - Andreas Köhn
- Institut für Theoretische Chemie
- Universität Stuttgart
- D-70569 Stuttgart
- Germany
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Product rotational angular momentum polarization of H+FCl (v=0-5; j=0, 3, 6, 9) → HF+Cl and HCl+F at Erel=0.5-20 kcal mol(-1). J Mol Model 2015; 21:309. [PMID: 26564146 DOI: 10.1007/s00894-015-2827-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Accepted: 09/22/2015] [Indexed: 10/22/2022]
Abstract
The rotational angular momentum polarizations of product molecules of the title reactions on the ground potential energy surface 1 (2)A' of DHTSN [Deskevic et al. J Chem Phys 2006, 124, 224303] have been studied using the quasi-classical trajectory method. Reaction dynamic results of the HF product channel comparing with another channel of HCl with 100,000 trajectories can be accurately resolved. We show the value of the polar p(ϑr) in the range of 0° ≤ ϑr ≤ 180(°), azimuthal p(φr) in the range of 0° ≤ φr ≤ 360(°), and dihedral p(ϑr, φr) in the ranges of 0(°) ≤ ϑr ≤ 180(°) and 0(°) ≤ φr ≤ 360(°); the angular distributions of the product molecules HF and HCl at relative Erel = 0.5, 1, 2, 5, 10, 15, and 20 kcal mol(-1); and four polarization-dependent differential cross sections (PDDCSs) of HF and HCl at Erel = 0.5, 1, 2, 5, 10, and 15 kcal mol(-1). p(φr) distributions at v = 0-5, and j = 0, 3, 6, 9 at every Erel are plotted cylindrically together. The stereo dynamic transformation reaction dependent upon the rovibrational states of the reactant molecule FCl and its relative translational energies around 0.5-5 kcal mol(-1) can be significantly differentiated. Translational and rovibrational enhancements of the title reactions on both early barrier potential energy surfaces have been shown in great detail and clarified. Reaction mechanisms of forward and backward scattering of the product molecules HF and HCl, respectively, have been obtained. Graphical Abstract H + FCl → either HF + Cl (left) or HCl + F (right) is moving along a trajectory on the respective PES.
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MA JIANJUN. Effects of collision energy on stereodynamical information of the reaction F+HI→FI+H. J CHEM SCI 2015. [DOI: 10.1007/s12039-015-0921-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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He X, Wu H, Zhang P, Zhang Y. Quantum State-to-State Dynamics of the H + LiH → H2 + Li Reaction. J Phys Chem A 2015. [DOI: 10.1021/acs.jpca.5b05178] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Xiaohu He
- School of Chemical Engineering, Dalian University of Technology, Dalian 116023, China
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute
of Chemical Physics, Chinese Academy of Science, Dalian 116023, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hui Wu
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute
of Chemical Physics, Chinese Academy of Science, Dalian 116023, China
| | - Peiyu Zhang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute
of Chemical Physics, Chinese Academy of Science, Dalian 116023, China
| | - Yan Zhang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute
of Chemical Physics, Chinese Academy of Science, Dalian 116023, China
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Burgess DR, Babushok VI, Linteris GT, Manion JA. A Chemical Kinetic Mechanism for 2-Bromo-3,3,3-trifluoropropene (2-BTP) Flame Inhibition. INT J CHEM KINET 2015. [DOI: 10.1002/kin.20923] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Donald R. Burgess
- Chemical Sciences Division, National Institute of Standards and Technology; Gaithersburg 20899
| | - Valeri I. Babushok
- Fire Research Division; National Institute of Standards and Technology; Gaithersburg 20899
| | - Gregory T. Linteris
- Fire Research Division; National Institute of Standards and Technology; Gaithersburg 20899
| | - Jeffrey A. Manion
- Chemical Sciences Division, National Institute of Standards and Technology; Gaithersburg 20899
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Zhao J, Miao X, Luo Y. Time-dependent wave packet quantum scattering and quasi-classical trajectory calculations of the H + FCl(v=0,j=0) → HF + Cl/HCl + F reaction. J Phys Chem A 2013; 117:11411-9. [PMID: 24125031 DOI: 10.1021/jp4070592] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The dynamics of the title reaction are investigated using both time-dependent wave packet quantum scattering and quasi-classical trajectory (QCT) methods on adiabatic ground 1(2)A' potential energy surface (PES). Compared with the quantum results of reaction probabilities of H + FCl(J=0) → HF + Cl/HCl + F, the QCT method is proven feasible and further employed to produce integral cross sections and rate constants. Significant resonance structures are observed in the reaction probabilities using the quantum method; however, there are some undulations in the calculated QCT integral cross sections for both product channels. A comparison between the quantum mechanical coupled-channel (CC) calculation and centrifugal sudden approximation calculation reveals the very important role of Coriolis coupling effects in the quantum calculation. Comparisons between the calculated thermal rate constants for both reactions and the previous theoretical and experimental results have been done. HCl product formation is favored over the HF product in the reactive system. Finally, the HF products are found to be mainly forward scattering, and the HCl products are mainly backward scattering.
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Affiliation(s)
- Juan Zhao
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences , Dalian 116023, China
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Li A, Guo H, Sun Z, Kłos J, Alexander MH. State-to-state quantum dynamics of the F + HCl (vi = 0, ji = 0) → HF(vf, jf) + Cl reaction on the ground state potential energy surface. Phys Chem Chem Phys 2013; 15:15347-55. [DOI: 10.1039/c3cp51870a] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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ZHANG LI, ZHU CHAOYONG, JIANG GANG, ZHU CHAOYUAN, ZHU ZH. A QUASICLASSICAL TRAJECTORY STUDY OF REACTIVE SCATTERING ON AN ANALYTICAL POTENTIAL ENERGY SURFACE FOR GeH2 SYSTEM. JOURNAL OF THEORETICAL & COMPUTATIONAL CHEMISTRY 2012. [DOI: 10.1142/s0219633611006426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
A quasiclassical trajectory method was employed to study reaction Ge+H 2 (v=0, j=0) and reverse reaction H+GeH (v=0, j=0) on an analytical potential energy surface obtained from simplified many-body expansion method with fitting to B3P86/CC-pVTZ calculations around a global minimum and a long-range van de Waals well plus spectroscopy data for diatomic molecules GeH and H2 . Reaction probabilities from both reaction and reverse reaction were calculated. Dominant reaction is complex-forming reaction Ge+H2 (v=0, j=0) → GeH2 , and its cross section is 10 times bigger than that of complex-forming reaction from the reverse reaction. There is no threshold effect for complex-forming reaction and the cross sections for both complex-forming reactions decrease with the increase of collision energy. Life time of complex is shown to be decreasing with increase of collision energy. Dominant reverse reaction is reaction H + GeH (v=0,j=0) → Ge+H2 ; the reaction probability decreases with the increase of collision energy and differential cross section shows that this reverse reaction has almost equal angular distribution at low collision energy and mostly forward scattering at high collision energy.
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Affiliation(s)
- LI ZHANG
- Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, P. R. China
| | - CHAO-YONG ZHU
- Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, P. R. China
| | - GANG JIANG
- Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, P. R. China
| | - CHAOYUAN ZHU
- Department of Applied Chemistry, Institute of Molecular Science and Center for Interdisciplinary Molecular Science, National Chiao-Tung University, Hsinchu 30050, Taiwan
| | - Z. H. ZHU
- Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, P. R. China
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12
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Duan ZX, Li WL, Qiu MH. Influence of collision energy and reagent rotation on the cross sections and product polarizations of the reaction F+ HCl. J Chem Phys 2012; 136:144309. [DOI: 10.1063/1.3701825] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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13
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A quasiclassical trajectory analysis of stereodynamics of the H + FCl (v = 0 – 3, j = 0 – 3) → HCl + F reaction. J CHEM SCI 2011. [DOI: 10.1007/s12039-011-0063-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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14
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Wu VWK. Product rotational angular momentum polarization in the H+FCl(v=0-5, j=0, 3, 6, 9)→HF+Cl reaction. Phys Chem Chem Phys 2011; 13:9407-17. [PMID: 21479325 DOI: 10.1039/c0cp02416c] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The product alignment and orientation of the title reaction on the ground potential energy surface of 1 (2)A' have been studied using the quasi-classical trajectory method. The calculations were carried out for case (a) at collision energies of 0.5-20 kcal mol(-1) with the initially rovibrational state of the reagent FCl molecule being at the v = 0 and j = 0 level to especially reveal in detail the dependence of the product integral cross section on collision energy. Further calculations at the collision energy of 15 kcal mol(-1) for case (b) at v = 0-5, and j = 0, and (c) at v = 0, and j = 3, 6, 9 initial states were carried out to reveal the effect of initially vibrational and rotational excitations on stereodynamics, respectively. Possessing final relative velocity k' (defined as a vector in the xz-plane), product alignment perpendicular to the reagent relative velocity vector k (defined as z- or parallel to the z-axis), for case (a) is found to be weaker at all collision energies, for case (b) is found to be vibrationally enhanced by the reactant molecule FCl, but for case (c), rather insensitive to initially rotational excitation. The rotational vector of product molecular orientation pointing to either negative or positive direction of the y-axis in the center of mass frame, e.g. origin of the coordinate system, is enhanced by collision energies regarding to 0.5-20 kcal mol(-1), while it becomes weaker at higher vibrational (v = 0-5) or rotational (j = 0, 3, 6, 9) excitation levels. Effects of collision energies and of rotational excitation at these collision energies, with 15 kcal mol(-1) as an example on the calculated PDDCSs are also shown and discussed. Detailed plots P(φ(r)) in the range of 0 ≤φ(r)≤ 360(o), and P(θ(r), φ(r)) in the ranges of 0 ≤θ(r)≤ 180° and 0 ≤φ(r)≤ 360° at collision energies 0.5-20 kcal mol(-1) have been presented. Overall, results of PDDCSs of the product alignment and product orientation at these collision energies in the title reaction are not very strongly distinguishable.
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Affiliation(s)
- Victor Wei-Keh Wu
- Department of Chemical and Materials Engineering, National Kaohsiung University of Applied Sciences, 80782 Kaohsiung, Taiwan.
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Peng Y. Quasiclassical Trajectory Calculations of the Isotope Effect: Chemical Stereodynamics for the H(D) + FCl ( v= 0–3, j= 0–3) → HCl(DCl) + F Reactions. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2010. [DOI: 10.1246/bcsj.20100022] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Quéméner G, Balakrishnan N. Cold and ultracold chemical reactions of F+HCl and F+DCl. J Chem Phys 2008; 128:224304. [DOI: 10.1063/1.2928804] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
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Zolot AM, Nesbitt DJ. Quantum state resolved scattering dynamics of F+HCl→HF(v,J)+Cl. J Chem Phys 2007; 127:114319. [PMID: 17887849 DOI: 10.1063/1.2770464] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
State-to-state reaction dynamics of the reaction F+HCl-->HF(v,J)+Cl have been studied under single-collision conditions using an intense discharge F atom source in crossed supersonic molecular beams at Ecom=4.3(1.3) kcal/mol. Nascent HF product is monitored by shot-noise limited direct infrared laser absorption, providing quantum state distributions as well as additional information on kinetic energy release from high resolution Dopplerimetry. The vibrational distributions are highly inverted, with 34(4)%, 44(2)%, and 8(1)% of the total population in vHF=1, 2, and 3, respectively, consistent with predominant energy release into the newly formed bond. However, there is a small [14(1)%] but significant formation channel into the vHF=0 ground state, which is directly detectable for the first time via direct absorption methods. Of particular dynamical interest, both the HF(v=2,J) and HF(v=1,J) populations exhibit strongly bimodal J distributions. These results differ significantly from previous flow and arrested-relaxation studies and may signal the presence of microscopic branching in the reaction dynamics.
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Affiliation(s)
- A M Zolot
- JILA, National Institute of Standards and Technology and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309, USA
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Deskevich MP, Hayes MY, Takahashi K, Skodje RT, Nesbitt DJ. Multireference configuration interaction calculations for the F(P2)+HCl→HF+Cl(P2) reaction: A correlation scaled ground state (1A′2) potential energy surface. J Chem Phys 2006; 124:224303. [PMID: 16784270 DOI: 10.1063/1.2192505] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
This paper presents a new ground state (1 (2)A(')) electronic potential energy surface for the F((2)P)+HCl-->HF+Cl((2)P) reaction. The ab initio calculations are done at the multireference configuration interaction+Davidson correction (MRCI+Q) level of theory by complete basis set extrapolation of the aug-cc-pVnZ (n=2,3,4) energies. Due to low-lying charge transfer states in the transition state region, the molecular orbitals are obtained by six-state dynamically weighted multichannel self-consistent field methods. Additional perturbative refinement of the energies is achieved by implementing simple one-parameter correlation energy scaling to reproduce the experimental exothermicity (DeltaE=-33.06 kcalmol) for the reaction. Ab initio points are fitted to an analytical function based on sum of two- and three-body contributions, yielding a rms deviation of <0.3 kcalmol for all geometries below 10 kcalmol above the barrier. Of particular relevance to nonadiabatic dynamics, the calculations show significant multireference character in the transition state region, which is located 3.8 kcalmol with respect to F+HCl reactants and features a strongly bent F-H-Cl transition state geometry (theta approximately 123.5 degrees ). Finally, the surface also exhibits two conical intersection seams that are energetically accessible at low collision energies. These seams arise naturally from allowed crossings in the C(infinityv) linear configuration that become avoided in C(s) bent configurations of both the reactant and product, and should be a hallmark of all X-H-Y atom transfer reaction dynamics between ((2)P) halogen atoms.
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Affiliation(s)
- Michael P Deskevich
- JILA, National Institute of Standards and Technology, University of Colorado, Boulder, Colorado 80309, USA
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Hayes MY, Deskevich MP, Nesbitt DJ, Takahashi K, Skodje RT. A Simple Picture for the Rotational Enhancement of the Rate for the F + HCl → HF + Cl Reaction: A Dynamical Study Using a New ab initio Potential Energy Surface. J Phys Chem A 2005; 110:436-44. [PMID: 16405315 DOI: 10.1021/jp0535745] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Quantum scattering calculations for the reaction F + HCl --> HF + Cl are performed on a new ground-state ab initio potential energy surface. The reagent rotation is found to have a dramatic effect on the reaction probability. Furthermore, the exit channel rotational thresholds leave a strong imprint on the reaction probabilities and even on the cumulative reaction probability. A very simple vibrationally adiabatic model is shown to account for most aspects of the reaction dynamics. In this model, the fast vibrational motion is adiabatically eliminated leaving the key reaction dynamics represented by a reduced atom + rotor collision. The shape of the adiabatic potential surface immediately yields to a simple and intuitive interpretation for the rotational enhancement of the rate. The rotational enhancement is shown to be an effect of the entrance channel dynamics of the atom-rotor problem.
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Affiliation(s)
- Michael Y Hayes
- Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309, USA
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