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Goswami S, San Vicente Veliz JC, Upadhyay M, Bemish RJ, Meuwly M. Quantum and quasi-classical dynamics of the C( 3P) + O 2( 3Σ-g) → CO( 1Σ +) + O( 1D) reaction on its electronic ground state. Phys Chem Chem Phys 2022; 24:23309-23322. [PMID: 36165004 PMCID: PMC9533374 DOI: 10.1039/d2cp02840a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The dynamics of the C(3P) + O2(3Σ−g) → CO(1Σ+) + O(1D) reaction on its electronic ground state is investigated by using time-dependent wave packet propagation (TDWP) and quasi-classical trajectory (QCT) simulations. For the moderate collision energies considered (Ec = 0.001 to 0.4 eV, corresponding to a range from 10 K to 4600 K) the total reaction probabilities from the two different treatments of the nuclear dynamics agree very favourably. The undulations present in P(E) from the quantum mechanical treatment can be related to stabilization of the intermediate CO2 complex with lifetimes on the 0.05 ps time scale. This is also confirmed from direct analysis of the TDWP simulations and QCT trajectories. Product diatom vibrational and rotational level resolved state-to-state reaction probabilities from TDWP and QCT simulations agree well except for the highest product vibrational states (v′ ≥ 15) and for the lowest product rotational states (j′ ≤ 10). Opening of the product vibrational level CO(v′ = 17) requires ∼0.2 eV from QCT and TDWP simulations with O2(j = 0) and decreases to 0.04 eV if all initial rotational states are included in the QCT analysis, compared with Ec > 0.04 eV obtained from experiments. It is thus concluded that QCT simulations are suitable for investigating and realistically describe the C(3P) + O2(3Σ−g) → CO(1Σ+) + O(1D) reaction down to low collision energies when compared with results from a quantum mechanical treatment using TDWPs. The dynamics of the C(3P) + O2(3Σ−g) → CO(1Σ+) + O(1D) reaction on its electronic ground state is investigated by using time-dependent wave packet propagation (TDWP) and quasi-classical trajectory (QCT) simulations.![]()
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Affiliation(s)
- Sugata Goswami
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, CH-4056 Basel, Switzerland.
| | | | - Meenu Upadhyay
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, CH-4056 Basel, Switzerland.
| | - Raymond J Bemish
- Air Force Research Laboratory, Space Vehicles Directorate, Kirtland AFB, New Mexico 87117, USA
| | - Markus Meuwly
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, CH-4056 Basel, Switzerland. .,Department of Chemistry, Brown University, RI, USA
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Sathyamurthy N, Mahapatra S. Time-dependent quantum mechanical wave packet dynamics. Phys Chem Chem Phys 2020; 23:7586-7614. [PMID: 33306771 DOI: 10.1039/d0cp03929b] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Starting from a model study of the collinear (H, H2) exchange reaction in 1959, the time-dependent quantum mechanical wave packet (TDQMWP) method has come a long way in dealing with systems as large as Cl + CH4. The fast Fourier transform method for evaluating the second order spatial derivative of the wave function and split-operator method or Chebyshev polynomial expansion for determining the time evolution of the wave function for the system have made the approach highly accurate from a practical point of view. The TDQMWP methodology has been able to predict state-to-state differential and integral reaction cross sections accurately, in agreement with available experimental results for three dimensional (H, H2) collisions, and identify reactive scattering resonances too. It has become a practical computational tool in predicting the observables for many A + BC exchange reactions in three dimensions and a number of larger systems. It is equally amenable to determining the bound and quasi-bound states for a variety of molecular systems. Just as it is able to deal with dissociative processes (without involving basis set expansion), it is able to deal with multi-mode nonadiabatic dynamics in multiple electronic states with equal ease. We present an overview of the method and its strength and limitations, citing examples largely from our own research groups.
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Goswami S, Sahoo J, Paul SK, Rao TR, Mahapatra S. Effect of Reagent Vibration and Rotation on the State-to-State Dynamics of the Hydrogen Exchange Reaction, H + H 2 → H 2 + H. J Phys Chem A 2020; 124:9343-9359. [PMID: 33124827 DOI: 10.1021/acs.jpca.0c06707] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
State-to-state dynamics of the benchmark hydrogen exchange reaction H + H2 (v = 0-4, j = 0-3) → H2 (v', j') + H is investigated with the aid of the real wave packet approach of Gray and Balint-Kurti (J. Chem. Phys. 1998, 108, 950-962) and electronic ground BKMP2 potential energy surface of Boothroyd et al. (J. Chem. Phys. 1996, 104, 7139-7152). Initial state-selected and product state-resolved reaction probabilities, integral cross section, and product diatom vibrational and rotational level populations at a few collision energies are reported to elucidate the energy disposal mechanism. State-specific thermal rate constants are also calculated and compared with the available literature results. Coriolis coupling terms of the nuclear Hamiltonian are included, and calculations are parallelized over the helicity quantum number, Ω'. Attempts are made, in particular, to study the effect of reagent vibrational and rotational excitations on the dynamical attributes. It is found that the calculations become computationally expensive with reagent vibrational and rotational excitation. Reagent vibrational excitation is found to enhance the reactivity and has significant impact on the energy disposal to the vibrational and rotational degrees of freedom of the product. The interplay of reagent translational and vibrational energy on the product vibrational distribution unfolds an important aspect of the energy disposal mechanism. The effect of reagent rotation on the state-to-state dynamics is found not to be very significant, and the weak effect turns out to be specific to v'.
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Affiliation(s)
- Sugata Goswami
- School of Chemistry, University of Hyderabad, Hyderabad 500046, India
| | - Jayakrushna Sahoo
- School of Chemistry, University of Hyderabad, Hyderabad 500046, India
| | - Suranjan K Paul
- School of Chemistry, University of Hyderabad, Hyderabad 500046, India
| | - T Rajagopala Rao
- School of Chemistry, University of Hyderabad, Hyderabad 500046, India
| | - S Mahapatra
- School of Chemistry, University of Hyderabad, Hyderabad 500046, India
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Rivero Santamaría A, Dayou F, Rubayo-Soneira J, Monnerville M. Time-Dependent Quantum Wave Packet Study of the Si + OH → SiO + H Reaction: Cross Sections and Rate Constants. J Phys Chem A 2017; 121:1675-1685. [PMID: 28171718 DOI: 10.1021/acs.jpca.7b00174] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The dynamics of the Si(3P) + OH(X2Π) → SiO(X1Σ+) + H(2S) reaction is investigated by means of the time-dependent wave packet (TDWP) approach using an ab initio potential energy surface recently developed by Dayou et al. ( J. Chem. Phys. 2013 , 139 , 204305 ) for the ground X2A' electronic state. Total reaction probabilities have been calculated for the first 15 rotational states j = 0-14 of OH(v=0,j) at a total angular momentum J = 0 up to a collision energy of 1 eV. Integral cross sections and state-selected rate constants for the temperature range 10-500 K were obtained within the J-shifting approximation. The reaction probabilities display highly oscillatory structures indicating the contribution of long-lived quasibound states supported by the deep SiOH/HSiO wells. The cross sections behave with collision energies as expected for a barrierless reaction and are slightly sensitive to the initial rotational excitation of OH. The thermal rate constants show a marked temperature dependence below 200 K with a maximum value around 15 K. The TDWP results globally agree with the results of earlier quasi-classical trajectory (QCT) calculations carried out by Rivero-Santamaria et al. ( Chem. Phys. Lett. 2014 , 610-611 , 335 - 340 ) with the same potential energy surface. In particular, the thermal rate constants display a similar temperature dependence, with TDWP values smaller than the QCT ones over the whole temperature range.
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Affiliation(s)
- Alejandro Rivero Santamaría
- Laboratoire de Physique des Lasers, Atomes et Molécules, UMR 8523 du CNRS, Centre d'Études et de Recherches Lasers et Applications, Université Lille I , Bât. P5, 59655 Villeneuve d'Ascq Cedex, France
| | - Fabrice Dayou
- LERMA, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Universités , UPMC Univ. Paris 06, F-75252 Paris, France
| | - Jesus Rubayo-Soneira
- Departamento de Física General, Instituto Superior de Tecnologías y Ciencias Aplicadas , Habana 10600, Cuba
| | - Maurice Monnerville
- Laboratoire de Physique des Lasers, Atomes et Molécules, UMR 8523 du CNRS, Centre d'Études et de Recherches Lasers et Applications, Université Lille I , Bât. P5, 59655 Villeneuve d'Ascq Cedex, France
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Koner D, Barrios L, González-Lezana T, Panda AN. Scattering study of the Ne + NeH(+)(v0 = 0, j0 = 0) → NeH(+) + Ne reaction on an ab initio based analytical potential energy surface. J Chem Phys 2016; 144:034303. [PMID: 26801030 DOI: 10.1063/1.4939952] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Initial state selected dynamics of the Ne + NeH(+)(v0 = 0, j0 = 0) → NeH(+) + Ne reaction is investigated by quantum and statistical quantum mechanical (SQM) methods on the ground electronic state. The three-body ab initio energies on a set of suitably chosen grid points have been computed at CCSD(T)/aug-cc-PVQZ level and analytically fitted. The fitting of the diatomic potentials, computed at the same level of theory, is performed by spline interpolation. A collinear [NeHNe](+) structure lying 0.72 eV below the Ne + NeH(+) asymptote is found to be the most stable geometry for this system. Energies of low lying vibrational states have been computed for this stable complex. Reaction probabilities obtained from quantum calculations exhibit dense oscillatory structures, particularly in the low energy region and these get partially washed out in the integral cross section results. SQM predictions are devoid of oscillatory structures and remain close to 0.5 after the rise at the threshold thus giving a crude average description of the quantum probabilities. Statistical cross sections and rate constants are nevertheless in sufficiently good agreement with the quantum results to suggest an important role of a complex-forming dynamics for the title reaction.
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Affiliation(s)
- Debasish Koner
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781039, India
| | - Lizandra Barrios
- IFF-CSIC, Instituto de Física Fundamental, CSIC, Serrano 123, Madrid 28006, Spain
| | | | - Aditya N Panda
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781039, India
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Koner D, Barrios L, González-Lezana T, Panda AN. Quantum, Statistical, and Quasiclassical Trajectory Studies For the Ne + HeH(+) → NeH(+) + He Reaction on the Ground Electronic State. J Phys Chem A 2015; 119:12052-61. [PMID: 26172109 DOI: 10.1021/acs.jpca.5b04830] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Real wave packet, statistical quantum, and quasiclassical trajectory methods were employed to study the dynamics of Ne + HeH(+)(v0,j0) → He + NeH(+) reaction on an ab initio potential energy surface [J. Phys. Chem. A 2013, 117, 13070-13078]. Quantum and statistical quantum calculations were performed within the centrifugal sudden (CS) approximation as well as including the Coriolis coupling (CC). Dense oscillatory structures of the quantum reaction probabilities and fair agreement between quantum and statistical cross sections suggest a complex forming mechanism for the reaction. No significant differences between cross sections obtained within the CS and CC approaches are observed. Quasiclassical trajectory results give an excellent average description of the quantum CC results. At low collision energies, there is a substantial decrease in reactivity for the reaction upon rovibrational excitation. Initial state selected rate constants for the title reaction are calculated between 20 and 1000 K, and the calculated value at 300 K agrees quite well with the available experimental result. Reaction cross sections and rate constants are also compared with those calculated via the Langevin capture model for exothermic reactions.
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Affiliation(s)
- Debasish Koner
- Department of Chemistry, Indian Institute of Technology Guwahati, Assam 781039, India
| | - Lizandra Barrios
- Instituto de Física Fundamental, C.S.I.C. , Serrano 123, Madrid 28006, Spain
| | | | - Aditya N Panda
- Department of Chemistry, Indian Institute of Technology Guwahati, Assam 781039, India
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