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Rangel C, Garcia-Chamorro M, Corchado JC, Espinosa-Garcia J. Kinetics and dynamics study of the OH + C 2H 6 → H 2O + C 2H 5 reaction based on an analytical global potential energy surface. Phys Chem Chem Phys 2020; 22:14796-14810. [PMID: 32578642 DOI: 10.1039/d0cp02776f] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
To describe the gas-phase hydrogen abstraction reaction between the hydroxyl radical and the ethane molecule, an analytical full-dimensional potential energy surface was developed within the Born-Oppenheimer approximation. This reactive process is a ten-body system with 24 degrees of freedom, which represents a theoretical challenge. The new surface, named PES-2020, presents low barrier, 3.76 kcal mol-1, high exothermicity, -16.20 kcal mol-1, and intermediate complexes in the entrance and exit channels. To test the quality and accuracy of the analytical surface several stringent tests were performed and, in general, PES-2020 reasonably simulates the theoretical information used as input, it is a continuous and smooth potential, without spurious minima, it presents great versatility and a reasonable description of this ten-body reaction. Based on this surface, an exhaustive kinetics and dynamics study was performed with a double objective: to analyze the capacity of the new surface to simulate the experimental evidence, and to help understand the mechanism of reaction and the role of the ethyl group in the reaction. In the kinetics study, three approaches were used: variational transition-state theory with multidimensional tunnelling (VTST/MT), ring polymer molecular dynamics (RPMD) and quasi-classical trajectory (QCT) results, in the temperature range 200-2000 K. There is general agreement between the three approaches and they reasonably simulate the experimental behaviour, which gives confidence to the fitness of the new surface to describe the system. In the dynamics study, QCT calculations were performed at 298 K for a direct comparison with the only experimental result reported. We found that ethyl fragment presents a noticeable internal energy (∼20%) and so cannot be considered as a spectator. The water product vibrational energy is reasonably reproduced, though when a level-by-level distribution is analyzed the agreement is only qualitative.
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Affiliation(s)
- C Rangel
- Departamento de Química Física and Instituto de Computación Científica Avanzada, Universidad de Extremadura, 06071 Badajoz, Spain.
| | - M Garcia-Chamorro
- Departamento de Química Física and Instituto de Computación Científica Avanzada, Universidad de Extremadura, 06071 Badajoz, Spain.
| | - J C Corchado
- Departamento de Química Física and Instituto de Computación Científica Avanzada, Universidad de Extremadura, 06071 Badajoz, Spain.
| | - J Espinosa-Garcia
- Departamento de Química Física and Instituto de Computación Científica Avanzada, Universidad de Extremadura, 06071 Badajoz, Spain.
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2
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Espinosa-Garcia J, Martinez-Nuñez E, Rangel C. Quasi-Classical Trajectory Dynamics Study of the Cl( 2P) + C 2H 6 → HCl(v,j) + C 2H 5 Reaction. Comparison with Experiment. J Phys Chem A 2018; 122:2626-2633. [PMID: 29489365 DOI: 10.1021/acs.jpca.8b00149] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
To understand and simulate the dynamics behavior of the title reaction, QCT calculations were performed on a recently developed global analytical potential energy surface, PES-2017. These calculations combine the classical description of the dynamics with pseudoquantization in the reactants and products to perform a theoretical/experimental comparison on the same footing. Thus, in the products a series of constraints are included to analyze the HCl(v = 0,j) product, which is experimentally detected. At collision energies of 5.5 and 6.7 kcal mol-1 the largest fraction of available energy is deposited as translation, 67%, while the ethyl radical shows significant internal energy, 27%, and so it does not act as a spectator of the reaction, thus reproducing recent experimental evidence. The HCl(v=0, j) rotational distribution is cold, peaking at j = 2, only one unit hotter than experiment, which represents an error of 0.12 kcal mol-1. At a collision energy of 5.5 kcal mol-1 product translational distribution is slightly hotter than experiment, but at 6.7 kcal mol-1 agreement with recent experiments is practically quantitative, suggesting that the first experiments should be revised. In addition, we observe that the HCl(v=0, j) scattering distribution shifts from isotropic at low values of j to backward at high values of j, which is in agreement with experimental data. Finally, no evidence was found for the "chattering" mechanism suggested to explain the low translational energy of the HCl product in the backward scattering region. In sum, agreement with experiments of a series of sensible dynamic properties permits us to be optimistic on the quality and accuracy of the theoretical tools used in the present work, QCT and PES-2017.
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Affiliation(s)
- Joaquin Espinosa-Garcia
- Departamento de Química Física and Instituto de Computacion Cientifica Avanzada , Universidad de Extremadura , 06071 Badajoz , Spain
| | - Emilio Martinez-Nuñez
- Departamento de Química Física , Universidad de Santiago de Compostela , Santiago de Compostela , Spain
| | - Cipriano Rangel
- Departamento de Química Física and Instituto de Computacion Cientifica Avanzada , Universidad de Extremadura , 06071 Badajoz , Spain
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3
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Vibrational distribution and dynamics study of the HCN(v
1, v
2, v
3) product in the CN + CH4 hydrogen abstraction reaction. Theor Chem Acc 2017. [DOI: 10.1007/s00214-017-2155-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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4
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Espinosa-Garcia J, Bonnet L, Corchado JC. Theoretical Study of the Pair-Correlated F + CHD3(v = 0,ν1 = 1) Reaction: Effect of CH Stretching Vibrational Excitation. J Phys Chem A 2017; 121:4076-4092. [DOI: 10.1021/acs.jpca.7b02665] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Joaquin Espinosa-Garcia
- Departamento
de Química Física and Instituto de Computatión
Científica Avanzada, Universidad de Extremadura, 06071 Badajoz, Spain
| | - Laurent Bonnet
- CNRS, Institut
des Sciences Moleculaires, UMR 5255, 33405 Talence, and Université
de Bordeaux, Institut des Sciences Moleculaires, UMR 5255, 33405 Talence, France
| | - Jose C. Corchado
- Departamento
de Química Física and Instituto de Computatión
Científica Avanzada, Universidad de Extremadura, 06071 Badajoz, Spain
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5
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Monge-Palacios M, Corchado JC, Espinosa-Garcia J. Dynamics study of the OH + NH3 hydrogen abstraction reaction using QCT calculations based on an analytical potential energy surface. J Chem Phys 2014; 138:214306. [PMID: 23758370 DOI: 10.1063/1.4808109] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
To understand the reactivity and mechanism of the OH + NH3 → H2O + NH2 gas-phase reaction, which evolves through wells in the entrance and exit channels, a detailed dynamics study was carried out using quasi-classical trajectory calculations. The calculations were performed on an analytical potential energy surface (PES) recently developed by our group, PES-2012 [Monge-Palacios et al. J. Chem. Phys. 138, 084305 (2013)]. Most of the available energy appeared as H2O product vibrational energy (54%), reproducing the only experimental evidence, while only the 21% of this energy appeared as NH2 co-product vibrational energy. Both products appeared with cold and broad rotational distributions. The excitation function (constant collision energy in the range 1.0-14.0 kcal mol(-1)) increases smoothly with energy, contrasting with the only theoretical information (reduced-dimensional quantum scattering calculations based on a simplified PES), which presented a peak at low collision energies, related to quantized states. Analysis of the individual reactive trajectories showed that different mechanisms operate depending on the collision energy. Thus, while at high energies (E(coll) ≥ 6 kcal mol(-1)) all trajectories are direct, at low energies about 20%-30% of trajectories are indirect, i.e., with the mediation of a trapping complex, mainly in the product well. Finally, the effect of the zero-point energy constraint on the dynamics properties was analyzed.
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Affiliation(s)
- M Monge-Palacios
- Departamento de Química Física, Universidad de Extremadura, 06071 Badajoz, Spain
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6
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Gonzalez-Lavado E, Rangel C, Espinosa-Garcia J. Dynamics of the O(3P) + CH4 hydrogen abstraction reaction at hyperthermal collision energies. Phys Chem Chem Phys 2014; 16:8428-33. [DOI: 10.1039/c4cp00403e] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
QCT calculations on a full-dimensional analytical potential energy surface (PES-2014) reproduce the experimental dynamics at 64.0 kcal mol−1 for the O(3P) + CH4 reaction.
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Affiliation(s)
- E. Gonzalez-Lavado
- Departamento de Química Física
- Universidad de Extremadura
- 06071 Badajoz, Spain
| | - C. Rangel
- Departamento de Química Física
- Universidad de Extremadura
- 06071 Badajoz, Spain
| | - J. Espinosa-Garcia
- Departamento de Química Física
- Universidad de Extremadura
- 06071 Badajoz, Spain
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7
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Abstract
I seem to have started off on the wrong foot in life, but I am extremely fortunate that I soon found my footing in the company of physical chemists. I consider myself to be very lucky to be doing something that constantly brings me in contact with bright minds, stimulating conversations, and exciting experiments. My work has allowed me to learn astounding facts about the molecules and atoms that make up our surroundings and ourselves. For this article, I focus on one aspect of my research, understanding the fundamental principles of the simple reaction between a hydrogen atom and a hydrogen molecule. Although my group and others have been studying this seemingly simple reaction for well over 30 years, it continues to provoke questions about the properties of matter.
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Affiliation(s)
- Richard N. Zare
- Department of Chemistry, Stanford University, Stanford, California 94305-5080
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Jankunas J, Sneha M, Zare RN, Bouakline F, Althorpe SC. Disagreement between theory and experiment grows with increasing rotational excitation of HD(v′, j′) product for the H + D2 reaction. J Chem Phys 2013; 138:094310. [DOI: 10.1063/1.4793557] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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9
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Isotope effects on the dynamics properties and reaction mechanism in the Cl(2P) + NH3 reaction: a QCT and QM study. Theor Chem Acc 2013. [DOI: 10.1007/s00214-013-1349-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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10
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Monge-Palacios M, Yang M, Espinosa-García J. QCT and QM calculations of the Cl(2P) + NH3 reaction: influence of the reactant well on the dynamics. Phys Chem Chem Phys 2012; 14:4824-34. [PMID: 22388701 DOI: 10.1039/c2cp00008c] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A detailed dynamics study, using both quasi-classical trajectory (QCT) and reduced-dimensional quantum mechanical (QM) calculations, was carried out to understand the reactivity and mechanism of the Cl((2)P) + NH(3)→ HCl + NH(2) gas-phase reaction, which evolves through deep wells in the entry and exit channels. The calculations were performed on an analytical potential energy surface recently developed by our group, PES-2010 [M. Monge-Palacios, C. Rangel, J. C. Corchado and J. Espinosa-Garcia, Int. J. Quantum. Chem., 2011], together with a simplified model surface, mod-PES, in which the reactant well is removed to analyze its influence. The main finding was that the QCT and QM methods show a change of the reaction probability with collision energy, suggesting a change of the atomic-level mechanism of reaction with energy. This change disappeared when the mod-PES was used, showing that the behaviour at low energies is a direct consequence of the existence of the reactant well. Analysis of the trajectories showed that different mechanisms operate depending on the collision energy. Thus, while at high energies (E(coll) > 5 kcal mol(-1)) practically all trajectories are direct, at low energies (E(coll) < 3 kcal mol(-1)) the trajectories are indirect, i.e., with the mediation of a trapping complex in the entry and/or the exit wells. The reactant complex allows repeated encounters between the reactants, increasing the reaction probability at low energies. The differential cross section results reinforce this change of mechanism, showing also the influence of the reactant well on this reaction. Thus, the PES-2010 surface yields a forward-backward symmetry in the scattering, while when the reactant well is removed with the mod-PES the shape is more isotropic.
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Affiliation(s)
- M Monge-Palacios
- Departamento de Química Física, Universidad de Extremadura, 06071 Badajoz, Spain
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11
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12
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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)
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13
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Chu TS, Han KL, Hankel M, Balint-Kurti GG, Kuppermann A, Abrol R. Nonadiabatic effects in the H+H2 exchange reaction: Accurate quantum dynamics calculations at a state-to-state level. J Chem Phys 2009; 130:144301. [DOI: 10.1063/1.3089724] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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14
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15
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Espinosa-García J, Nyman G, Corchado JC. The hydrogen abstraction reaction H+CH[sub 4]. II. Theoretical investigation of the kinetics and dynamics. J Chem Phys 2009; 130:184315. [DOI: 10.1063/1.3132594] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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16
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Espinosa-García J. Quasi-classical trajectory study of the hydrogen abstraction F+CHD3 reaction: A state-to-state dynamics analysis. Chem Phys Lett 2008. [DOI: 10.1016/j.cplett.2008.02.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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17
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Rangel C, Corchado JC, Espinosa-García J. Quasi-classical trajectory calculations in asymmetrically substituted polyatomic systems of the type A + CX3Y → products: the H + CH3Cl hydrogen abstraction reaction channel. Phys Chem Chem Phys 2008; 10:6776-86. [DOI: 10.1039/b809999e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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18
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Teslja A, Valentini JJ. State-to-state reaction dynamics: A selective review. J Chem Phys 2006; 125:132304. [PMID: 17029423 DOI: 10.1063/1.2354466] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A selective review of state-to-state reaction dynamics experiments is presented. The review focuses on three classes of reactions that exemplify the rich history and illustrate the current state of the art in such work. These three reactions are (1) the hydrogen exchange reaction, H+H2-->H2+H and its isotopomers; (2) the H+RH-->H2+R reactions, where RH is an alkane, beginning with H+CH4-->H2+CH3 and extending to much larger alkanes; and (3) the Cl+RH-->HCl+R reactions, principally Cl+CH4-->HCl+CH3. We describe the experiments, discuss their results, present comparisons with theory, and introduce heuristic models.
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Affiliation(s)
- Alexey Teslja
- Department of Chemistry, Columbia University, New York, New York 10027, USA
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19
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Berger R, Laubender G, Quack M, Sieben A, Stohner J, Willeke M. Isotopic chirality and molecular parity violation. Angew Chem Int Ed Engl 2006; 44:3623-6. [PMID: 15880539 DOI: 10.1002/anie.200462088] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Robert Berger
- Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 135, 10623 Berlin, Germany
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20
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Liu Y, Liu Z, Lv G, Jiang L, Sun J. Product polarization distribution: Stereodynamics of the reactions Cl+CH4→HCl+CH3 and Cl+CD4→DCl+CD3. Chem Phys Lett 2006. [DOI: 10.1016/j.cplett.2006.03.059] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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21
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Rangel C, Navarrete M, Corchado JC, Espinosa-García J. Potential energy surface, kinetics, and dynamics study of the Cl+CH4→HCl+CH3 reaction. J Chem Phys 2006; 124:124306. [PMID: 16599673 DOI: 10.1063/1.2179067] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A modified and recalibrated potential energy surface for the gas-phase Cl+CH4-->HCl+CH3 reaction is reported and tested. It is completely symmetric with respect to the permutation of the four methane hydrogen atoms and is calibrated with respect to updated experimental and theoretical stationary point properties and experimental forward thermal rate constants. From the kinetics point of view, the forward and reverse thermal rate constants and the activation energies were calculated using the variational transition-state theory with semiclassical transmission coefficients over a wide temperature range of 150-2500 K. The theoretical results reproduce the available experimental data, with a small curvature of the Arrhenius plot which indicates the role of tunneling in this hydrogen abstraction reaction. A dynamics study was also performed on this PES using quasiclassical trajectory (QCT) calculations, including corrections to avoid zero-point energy leakage along the trajectories. First, we found a noticeable internal energy in the coproduct methyl radical, both in the ground-state [CH4 (v=0)] and vibrationally excited [CH4 (v=1)] reactions. This CH3 internal energy was directly precluded in some experiments or oversimplified in previous theoretical studies using pseudotriatomic models. Second, our QCT calculations give HCl rotational distributions slightly hotter than those in experiment, but correctly describing the experimental trend of decreasing the HCl product rotation excitation in going from HCl (v'=0) to HCl (v'=1) for the CH4 (v=1) reaction. Third, the state specific scattering distributions present a reasonable agreement with experiment, although they tend to make the reaction more forward and backward scattered than found experimentally probably because of the hotter rotational distribution and the deficiencies of the QCT methods.
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Affiliation(s)
- Cipriano Rangel
- Departamento de Química Física, Universidad de Extremadura, 06071 Badajoz, Spain
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22
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Koszinowski K, Goldberg NT, Pomerantz AE, Zare RN, Juanes-Marcos JC, Althorpe SC. Collision-energy dependence of HD(ν′=1,j′) product rotational distributions for the H+D2 reaction. J Chem Phys 2005; 123:054306. [PMID: 16108638 DOI: 10.1063/1.1978871] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Product rotational distributions for the reaction H + D2 --> HD(nu'=1,j') + D have been measured for 16 collision energies in the range of 1.43 < or = E(coll) < or = 2.55 eV. Time-dependent quantum-mechanical calculations agree well in general with the experimental results, but they consistently yield slightly colder distributions. In terms of the average energy channeled into rotation, the differences between experiment and theory amount to approximately 10% for all collision energies sampled. No peculiarity is found for E(coll)=2.55 eV at which the system has sufficient energy to access the first HD2 electronically excited state.
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Affiliation(s)
- Konrad Koszinowski
- Department of Chemistry, Stanford University, Stanford, California 94305-5080, USA
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23
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Berger R, Laubender G, Quack M, Sieben A, Stohner J, Willeke M. Isotopeneffekte durch Paritätsverletzung in chiralen Molekülen. Angew Chem Int Ed Engl 2005. [DOI: 10.1002/ange.200462088] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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24
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Aoiz * FJ, BaÑares L, Herrero VJ. The H+H2reactive system. Progress in the study of the dynamics of the simplest reaction. INT REV PHYS CHEM 2005. [DOI: 10.1080/01442350500195659] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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25
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Pomerantz AE, Ausfelder F, Zare RN, Juanes-Marcos JC, Althorpe SC, Sáez Rábanos V, Aoiz FJ, Bañares L, Castillo JF. Rovibrational product state distribution for inelastic H+D2 collisions. J Chem Phys 2004; 121:6587-90. [PMID: 15473712 DOI: 10.1063/1.1804940] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Experimental measurements of rovibrational product state distributions for the inelastic scattering process H + D2(nu=0,j)-->H + D2(nu' = 1,2,j') are presented and compared with the results of quasiclassical and quantum mechanical calculations. Agreement between theory and experiment is almost quantitative. Two subtle trends are found: the relative amount of energy in product rotational excitation decreases slightly with increasing collision energy and increases slightly with increasing product vibrational excitation. These trends are the reverse of what has been found for reactive scattering in which the opposite trends are much more pronounced.
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Affiliation(s)
- Andrew E Pomerantz
- Department of Chemistry, Stanford University, Stanford, California 94305-5080, USA
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26
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Pomerantz AE, Ausfelder F, Zare RN, Althorpe SC, Aoiz FJ, Banares L, Castillo JF. Disagreement between theory and experiment in the simplest chemical reaction: Collision energy dependent rotational distributions for H+D2→HD(ν′=3,j′)+D. J Chem Phys 2004; 120:3244-54. [PMID: 15268478 DOI: 10.1063/1.1641008] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We present experimental rotational distributions for the reaction H + D2 --> HD(nu' = 3,j') + D at eight different collision energies between 1.49 and 1.85 eV. We combine a previous measurement of the state-resolved excitation function for this reaction [Ayers et al., J. Chem. Phys. 119, 4662 (2003)] with the current data to produce a map of the relative reactive cross section as a function of both collision energy and rotational quantum number (an E-j' plot). To compare with the experimental data, we also present E-j' plots resulting from both time-dependent and time-independent quantum mechanical calculations carried out on the BKMP2 surface. The two calculations agree well with each other, but they produce rotational distributions significantly colder than the experiment, with the difference being more pronounced at higher collision energies. Disagreement between theory and experiment might be regarded as surprising considering the simplicity of this system; potential causes of this discrepancy are discussed.
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Affiliation(s)
- Andrew E Pomerantz
- Department of Chemistry, Stanford University, Stanford, California 94305-5080 USA
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27
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Himmel HJ, Downs AJ, Greene TM. Reactions of ground state and electronically excited atoms of main group elements: a matrix perspective. Chem Rev 2002; 102:4191-241. [PMID: 12428988 DOI: 10.1021/cr020405x] [Citation(s) in RCA: 129] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Hans-Jörg Himmel
- Institut für Anorganische Chemie, Universität Karlsruhe, Engesserstrasse, Geb 30.45, 76128 Karlsruhe, Germany.
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28
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Aoiz FJ, Bañares L, Castillo JF, Sokolovski D. Energy dependence of forward scattering in the differential cross section of the H+D2→HD(v′=3,j′=0)+D reaction. J Chem Phys 2002. [DOI: 10.1063/1.1490920] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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29
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Bean BD, Ayers JD, Fernández-Alonso F, Zare RN. State-resolved differential and integral cross sections for the reaction H+D2→HD(v′=3,j′=0–7)+D at 1.64 eV collision energy. J Chem Phys 2002. [DOI: 10.1063/1.1462576] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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