1
|
Zhou Y, Lu Y, Zhang Z, Zhang DH. An efficient and universal parallel algorithm for high-dimensional quantum dynamics in poly-atomic reactions. J Chem Phys 2024; 160:202502. [PMID: 38785279 DOI: 10.1063/5.0209245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2024] [Accepted: 05/06/2024] [Indexed: 05/25/2024] Open
Abstract
This study presents a parallel algorithm for high-dimensional quantum dynamics simulations in poly atomic reactions, integrating distributed- and shared-memory models. The distributions of the wave function and potential energy matrix across message passing interface processes are based on bundled radial and angular dimensions, with implementations featuring either two- or one-sided communication schemes. Using realistic parameters for the H + NH3 reaction, performance assessment reveals linear scalability, exceeding 90% efficiency with up to 600 processors. In addition, owing to the universal and concise structure, the algorithm demonstrates remarkable extensibility to diverse reaction systems, as demonstrated by successes with six-atom and four-atom reactions. This work establishes a robust foundation for high-dimensional dynamics studies, showcasing the algorithm's efficiency, scalability, and adaptability. The algorithm's potential as a valuable tool for unraveling quantum dynamics complexities is underscored, paving the way for future advancements in the field.
Collapse
Affiliation(s)
- Yong Zhou
- Anhui Province Key Laboratory for Control and Applications of Optoelectronic Information Materials, Department of Physics, Anhui Normal University, Wuhu 241000, People's Republic of China
- State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical and Computational Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, People's Republic of China
| | - Yunpeng Lu
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore 637371, Singapore
| | - Zhaojun Zhang
- State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical and Computational Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, People's Republic of China
| | - Dong H Zhang
- State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical and Computational Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, People's Republic of China
- Hefei National Laboratory, Hefei 230088, People's Republic of China
| |
Collapse
|
2
|
Jonusas M, Leroux K, Krim L. N + H surface reaction under interstellar conditions: Does the NH/NH2/NH3 distribution depend on N/H ratio? J Mol Struct 2020. [DOI: 10.1016/j.molstruc.2020.128736] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
3
|
Zhang Z, Gatti F, Zhang DH. Full dimensional quantum mechanical calculations of the reaction probability of the H + NH3 collision based on a mixed Jacobi and Radau description. J Chem Phys 2019; 150:204301. [DOI: 10.1063/1.5096047] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Zhaojun Zhang
- State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical and Computational Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, People’s Republic of China
| | - Fabien Gatti
- ISMO, Institut des Sciences Moléculaires d’Orsay—UMR 8214 CNRS/Université Paris-Sud, F-91405 Orsay, France
| | - Dong H. Zhang
- State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical and Computational Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, People’s Republic of China
| |
Collapse
|
4
|
Nguyen TL, Stanton JF. Ab initio thermal rate coefficients for H + NH3⇌ H2+ NH2. INT J CHEM KINET 2019. [DOI: 10.1002/kin.21255] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Thanh Lam Nguyen
- Quantum Theory ProjectDepartments of Chemistry and PhysicsUniversity of Florida Gainesville Florida
| | - John F. Stanton
- Quantum Theory ProjectDepartments of Chemistry and PhysicsUniversity of Florida Gainesville Florida
| |
Collapse
|
5
|
Fu B, Shan X, Zhang DH, Clary DC. Recent advances in quantum scattering calculations on polyatomic bimolecular reactions. Chem Soc Rev 2017; 46:7625-7649. [DOI: 10.1039/c7cs00526a] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This review surveys quantum scattering calculations on chemical reactions of polyatomic molecules in the gas phase published in the last ten years.
Collapse
Affiliation(s)
- Bina Fu
- State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical and Computational Chemistry
- Dalian Institute of Chemical Physics
- Chinese Academy of Sciences
- Dalian 116023
- China
| | - Xiao Shan
- Physical and Theoretical Chemistry Laboratory
- Department of Chemistry
- University of Oxford
- Oxford
- UK
| | - Dong H. Zhang
- State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical and Computational Chemistry
- Dalian Institute of Chemical Physics
- Chinese Academy of Sciences
- Dalian 116023
- China
| | - David C. Clary
- Physical and Theoretical Chemistry Laboratory
- Department of Chemistry
- University of Oxford
- Oxford
- UK
| |
Collapse
|
6
|
Song H, Yang M, Guo H. Communication: Equivalence between symmetric and antisymmetric stretching modes of NH3 in promoting H + NH3 → H2 + NH2 reaction. J Chem Phys 2016; 145:131101. [DOI: 10.1063/1.4963286] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Hongwei Song
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
| | - Minghui Yang
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
| | - Hua Guo
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, USA
| |
Collapse
|
7
|
Song H, Guo H. Effects of reactant rotational excitations on H2 + NH2 → H + NH3 reactivity. J Chem Phys 2014; 141:244311. [DOI: 10.1063/1.4904483] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Hongwei Song
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, USA
| | - Hua Guo
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, USA
| |
Collapse
|
8
|
Song H, Li J, Yang M, Lu Y, Guo H. Nine-dimensional quantum dynamics study of the H2+ NH2→ H + NH3reaction: a rigorous test of the sudden vector projection model. Phys Chem Chem Phys 2014; 16:17770-6. [DOI: 10.1039/c4cp02227k] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
9
|
Li J, Guo H. A nine-dimensional global potential energy surface for NH4(X2A1) and kinetics studies on the H + NH3 ↔ H2 + NH2 reaction. Phys Chem Chem Phys 2014; 16:6753-63. [DOI: 10.1039/c4cp00241e] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A nine-dimensional global potential energy surface (PES) for the NH4 system is developed from ∼105 high-level ab initio points and the hydrogen abstraction kinetics on the PES agree with experiment.
Collapse
Affiliation(s)
- Jun Li
- Department of Chemistry and Chemical Biology
- University of New Mexico
- Albuquerque, USA
| | - Hua Guo
- Department of Chemistry and Chemical Biology
- University of New Mexico
- Albuquerque, USA
| |
Collapse
|
10
|
YANG YANG, LIU RUI, WAN RENZHUO, YANG MINGHUI. SEVEN-DIMENSIONAL QUANTUM DYNAMICS STUDY OF THE H2 + NH2 → H + NH3 REACTION ON AN INTERPOLATED POTENTIAL ENERGY SURFACE. JOURNAL OF THEORETICAL & COMPUTATIONAL CHEMISTRY 2013. [DOI: 10.1142/s0219633613500545] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Initial-state-selected time-dependent wave packet dynamics studies have been performed for the H 2 + NH 2 → H + NH 3 reaction with a seven-dimensional model on a new interpolated ab initio potential energy surface (PES). The PES is constructed using modified Shepard interpolation Scheme and contains 1967 data points with ab initio calculations carried out on UCCSD(T)/aug-cc-pVTZ level. In the seven-dimensional model, NH 2 group keeps C2v symmetry and two NH bonds are fixed at their equilibrium values. The total reaction probabilities are calculated when (1) the two reactants are initially at their ground states; (2) NH 2 bending mode is excited, and (3) H 2 is on its first vibrational excited state. The integral cross sections are also reported for these initial states with centrifugal-sudden approximation. Thermal rate constants are calculated for the temperature range of 200–2000 K and compared with the previous calculated values and available experimental data. Good agreements between theory and experiments for the rate constants at intermediate temperature are achieved on this PES.
Collapse
Affiliation(s)
- YANG YANG
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Centre for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, P. R. China
| | - RUI LIU
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Centre for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, P. R. China
| | - RENZHUO WAN
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Centre for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, P. R. China
- School of Electronic and Electrical Engineering, Wuhan Textile University, Wuhan 430200, P. R. China
| | - MINGHUI YANG
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Centre for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, P. R. China
| |
Collapse
|
11
|
Bonnet L. Insights into the semiclassical Wigner treatment of bimolecular collisions. J Chem Phys 2013; 139:114108. [PMID: 24070280 DOI: 10.1063/1.4819954] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The semiclassical Wigner treatment of bimolecular collisions, proposed by Lee and Scully on a partly intuitive basis [J. Chem. Phys. 73, 2238 (1980)], is derived here from first principles. The derivation combines Heller's ideas [J. Chem. Phys. 62, 1544 (1975); ibid. 65, 1289 (1976); ibid. 75, 186 (1981)], the backward picture of molecular collisions [L. Bonnet, J. Chem. Phys. 133, 174108 (2010)] and the microreversibility principle.
Collapse
Affiliation(s)
- L Bonnet
- CNRS, University of Bordeaux, ISM, UMR 5255, 33405 Talence, France
| |
Collapse
|
12
|
|
13
|
Kraka E, Zou W, Freindorf M, Cremer D. Energetics and Mechanism of the Hydrogenation of XHn for Group IV to Group VII Elements X. J Chem Theory Comput 2012; 8:4931-43. [DOI: 10.1021/ct300631s] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Elfi Kraka
- CATCO Group, Department
of Chemistry, Southern Methodist
University, 3215 Daniel Ave, Dallas, Texas 75275-0314, United States
| | - Wenli Zou
- CATCO Group, Department
of Chemistry, Southern Methodist
University, 3215 Daniel Ave, Dallas, Texas 75275-0314, United States
| | - Marek Freindorf
- CATCO Group, Department
of Chemistry, Southern Methodist
University, 3215 Daniel Ave, Dallas, Texas 75275-0314, United States
| | - Dieter Cremer
- CATCO Group, Department
of Chemistry, Southern Methodist
University, 3215 Daniel Ave, Dallas, Texas 75275-0314, United States
| |
Collapse
|
14
|
Buchowiecki M. Quantum calculations of the temperature dependence of the rate constant and the equilibrium constant for the NH3+H⇌NH2+H2 reaction. Chem Phys Lett 2012. [DOI: 10.1016/j.cplett.2012.01.075] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
15
|
LIPING JU, RUIFENG LU. COMPARATIVE STUDY OF REACTION RATE CONSTANTS FOR THE NH3 + H → NH2 + H2 REACTION WITH GLOBE DYNAMICS AND TRANSITION STATE THEORIES. JOURNAL OF THEORETICAL & COMPUTATIONAL CHEMISTRY 2011. [DOI: 10.1142/s0219633609005325] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The nine-dimension quasi-classical trajectory (QCT) calculations have been carried out for the title reaction with a global potential energy surface (PES) constructed by Corchado and Espinosa-García (J Chem Phys106:4013, 1997). The detailed dynamics calculations cover the specific collision energies falling in the range of 0.62–3.04 eV, which are sufficient to fit the calculated reactive cross-sections into a barrier-type excitation function and to obtain the thermal rate constants. The present QCT rate constants are in good agreement with the recent quantum dynamics (QD) results, both of which are much lower than that of the previous variational transition state theory (VTST).
Collapse
Affiliation(s)
- JU LIPING
- Department of Physics, Shenyang Institute of Aeronautical Engineering, Shenyang 110136, P. R. China
| | - LU RUIFENG
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637616, Singapore
| |
Collapse
|
16
|
Corchado JC, Espinosa-Garcia J, Yang M. Kinetics and dynamics of the NH3 + H → NH2 + H2 reaction using transition state methods, quasi-classical trajectories, and quantum-mechanical scattering. J Chem Phys 2011; 135:014303. [PMID: 21744898 DOI: 10.1063/1.3605242] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
On a recent analytical potential energy surface developed by two of the authors, an exhaustive kinetics study, using variational transition state theory with multidimensional tunneling effect, and dynamics study, using both quasi-classical trajectory and full-dimensional quantum scattering methods, was carried out to understand the reactivity of the NH(3) + H → NH(2) + H(2) gas-phase reaction. Initial state-selected time-dependent wave packet calculations using a full-dimensional model were performed, where the total reaction probabilities were calculated for the initial ground vibrational state and for four excited vibrational states of ammonia. Thermal rate constants were calculated for the temperature range 200-2000 K using the three methods and compared with available experimental data. We found that (a) the total reaction probabilities are very small, (b) the symmetric and asymmetric N-H stretch excitations enhance the reactivity, (c) the quantum-mechanical calculated thermal rate constants are about one order of magnitude smaller than the transition state theory results, which reproduce the experimental evidence, and (d) quasi-classical trajectory calculations, which were performed with the main goal of analyzing the influence of the zero-point energy problem on the final dynamics results, reproduce the quantum scattering calculations on the same surface.
Collapse
Affiliation(s)
- Jose C Corchado
- Departamento de Química Física, Universidad de Extremadura, 06071 Badajoz, Spain.
| | | | | |
Collapse
|
17
|
Bonnet L, Espinosa-García J. The method of Gaussian weighted trajectories. V. On the 1GB procedure for polyatomic processes. J Chem Phys 2011; 133:164108. [PMID: 21033776 DOI: 10.1063/1.3481781] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
In recent years, many chemical reactions have been studied by means of the quasiclassical trajectory (QCT) method within the Gaussian binning (GB) procedure. The latter consists of "quantizing" the final vibrational actions in Bohr spirit by putting strong emphasis on the trajectories reaching the products with vibrational actions close to integer values. A major drawback of this procedure is that if N is the number of product vibrational modes, the amount of trajectories necessary to converge the calculations is ∼10(N)×larger than with the standard QCT method. Applying it to polyatomic processes is thus problematic. In a recent paper, however, Czakó and Bowman propose to quantize the total vibrational energy instead of the vibrational actions [G. Czakó and J. M. Bowman, J. Chem. Phys. 131, 244302 (2009)], a procedure called 1GB here. The calculations are then only ∼10 times more time consuming than with the standard QCT method, allowing thereby for considerable numerical saving. In this paper, we propose some theoretical arguments supporting the 1GB procedure and check its validity on model test cases as well as the prototype four-atom reaction OH+D(2)→HOD+D.
Collapse
Affiliation(s)
- L Bonnet
- Institut des Sciences Moléculaires, Université Bordeaux 1, 351 Cours de la Libération, 33405 Talence Cedex, France.
| | | |
Collapse
|
18
|
Espinosa-García J, Corchado JC. Quasi-Classical Trajectory Calculations of the Hydrogen Abstraction Reaction H + NH3. J Phys Chem A 2010; 114:6194-200. [DOI: 10.1021/jp101607n] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | - José C. Corchado
- Departamento de Química Física, Universidad de Extremadura, 06006 Badajoz (Spain)
| |
Collapse
|
19
|
|
20
|
Espinosa-Garcia J, Corchado JC. Analytical Potential Energy Surface and Kinetics of the NH3 + H → NH2 + H2 Hydrogen Abstraction and the Ammonia Inversion Reactions. J Phys Chem A 2010; 114:4455-63. [DOI: 10.1021/jp1001513] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | - J. C. Corchado
- Departamento de Química Física, Universidad de Extremadura, Spain
| |
Collapse
|
21
|
|
22
|
González-Martínez ML, Bonnet L, Larrégaray P, Rayez JC, Rubayo-Soneira J. Transformation from angle-action variables to Cartesian coordinates for polyatomic reactions. J Chem Phys 2009; 130:114103. [DOI: 10.1063/1.3089602] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
23
|
Ju LP, Han KL, Zhang JZH. Global dynamics and transition state theories: Comparative study of reaction rate constants for gas-phase chemical reactions. J Comput Chem 2009; 30:305-16. [DOI: 10.1002/jcc.21032] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
24
|
Modified potential energy surface and time-dependent wave packet dynamics study for Cl+CH4→HCl+CH3 reaction. Chem Phys 2008. [DOI: 10.1016/j.chemphys.2008.10.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
|
25
|
Yang M. Full dimensional time-dependent quantum dynamics study of the H+NH3→H2+NH2 reaction. J Chem Phys 2008; 129:064315. [DOI: 10.1063/1.2967854] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
26
|
Yang M, Corchado JC. Seven dimensional quantum dynamics study of the H2+NH2-->H+NH3 reaction. J Chem Phys 2007; 127:184308. [PMID: 18020640 DOI: 10.1063/1.2790902] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Initial state-selected time-dependent wave packet dynamics calculations have been performed for the H2+NH2-->H+NH3 reaction using a seven dimensional model on an analytical potential energy surface based on the one developed by Corchado and Espinosa-Garcia [J. Chem. Phys. 106, 4013 (1997)]. The model assumes that the two spectator NH bonds are fixed at their equilibrium values and nonreactive NH2 group keeps C2v symmetry and the rotation-vibration coupling in NH2 is neglected. The total reaction probabilities are calculated when the two reactants are initially at their ground states, when the NH2 bending mode is excited, and when H2 is on its first vibrational excited state, with total angular momentum J=0. The converged cross sections for the reaction are also reported for these initial states. Thermal rate constants and equilibrium constants are calculated for the temperature range of 200-2000 K and compared with transition state theory results and the available experimental data. The study shows that (a) the reaction is dominated by ground-state reactivity and the main contribution to the thermal rate constants is thought to come from this state, (b) the excitation energy of H2 was used to enhance reactivity while the excitation of the NH2 bending mode hampers the reaction, (c) the calculated thermal rate constants are very close to the experimental data and transition state theory results at high and middle temperature, while they are ten times higher than that of transition state theory at low temperature (T=200 K), and (d) the equilibrium constants results indicate that the approximations applied may have different roles in the forward and reverse reactions.
Collapse
Affiliation(s)
- Minghui Yang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, People's Republic of China.
| | | |
Collapse
|