1
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Krajňák V, Wiggins S. Roaming in acetaldehyde. J Chem Phys 2024; 160:244104. [PMID: 38912673 DOI: 10.1063/5.0212443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Accepted: 05/27/2024] [Indexed: 06/25/2024] Open
Abstract
We investigate roaming in the photodissociation of acetaldehyde (CH3CHO), providing insights into the contrasting roaming dynamics observed for this molecule compared to formaldehyde. We carry out trajectory studies for full-dimensional acetaldehyde, supplemented with an analysis of a two-degree-of-freedom restricted model and obtain evidence for two distinct roaming pathways. Trajectories exhibit roaming at both shorter (9-11.5 au) and larger (14.5-22.9 au) maximum CH3-HCO separations, characterized by differing amounts of HCO rotation. No roaming trajectories were found in the intervening gap region. The roaming dynamics near 14.5-22.9 au are well-reproduced by the restricted model and involve passage through a centrifugal barrier, analogous to formaldehyde roaming. However, the shorter-range 9-11.5 au roaming appears unique to acetaldehyde and is likely facilitated by repulsive interactions absent in the simplified models. Phase space analysis reveals that this additional roaming pathway is inaccessible in the reduced dimensionality system. The findings suggest that acetaldehyde's increased propensity for roaming compared to formaldehyde may arise from the presence of multiple distinct roaming mechanisms rather than solely the higher roaming fragment mass.
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Affiliation(s)
- Vladimír Krajňák
- School of Mathematics, University of Bristol, Fry Building, Woodland Road, Bristol BS8 1UG, United Kingdom
| | - Stephen Wiggins
- School of Mathematics, University of Bristol, Fry Building, Woodland Road, Bristol BS8 1UG, United Kingdom
- Department of Mathematics, United States Naval Academy, Chauvenet Hall, 572C Holloway Road, Annapolis, Maryland 21402-5002, USA
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2
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Guan Y, Xie C, Guo H, Yarkony DR. Toward a Unified Analytical Description of Internal Conversion and Intersystem Crossing in the Photodissociation of Thioformaldehyde. I. Diabatic Singlet States. J Chem Theory Comput 2023; 19:6414-6424. [PMID: 37698839 DOI: 10.1021/acs.jctc.3c00628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/13/2023]
Abstract
The photodissociation of thioformaldehyde is an archetypal system for the study of competition between internal conversion and intersystem crossing, which involves its two singlet states (S0 and S1) and two triplet states (T1 and T2). In order to perform accurate dynamic simulations, either quantum or quasi-classical, it is essential to construct an analytical representation for all necessary electronic structure data. In this work, a diabatic potential energy matrix (DPEM), Hd, for the two singlet states (S0 and S1) is reported. The analytical form of DPEM is symmetrized and constructed to reproduce adiabatic energies, energy gradients, and derivative couplings obtained from high-level multireference configuration interaction wave functions. The Hd is fully saturated in the molecular configuration space with a trajectory-guided point sampling approach. This Hd can provide the accurate description of the photodissociation of thioformaldehyde on its singlet states and is also a necessary part for incorporating the spin-orbit couplings into a unified diabatic framework. Preliminary quasi-classical trajectory simulations show that a roaming mechanism also exists in the molecular dissociation channel of thioformaldehyde.
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Affiliation(s)
- Yafu Guan
- State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical Computational Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, People's Republic of China
| | - Changjian Xie
- Institute of Modern Physics, Northwest University, Xi'an, Shaanxi 710069, People's Republic of China
| | - Hua Guo
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, United States
| | - David R Yarkony
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
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3
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Campbell JS, Nauta K, Hansen CS, Kable SH. POPTARTS: A New Method to Determine Quantum Yields in a Molecular Beam. J Phys Chem A 2022; 126:9268-9275. [DOI: 10.1021/acs.jpca.2c06289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Affiliation(s)
- Jyoti S. Campbell
- School of Chemistry, University of New South Wales, Kensington, NSW2052, Australia
| | - Klaas Nauta
- School of Chemistry, University of New South Wales, Kensington, NSW2052, Australia
| | | | - Scott H. Kable
- School of Chemistry, University of New South Wales, Kensington, NSW2052, Australia
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4
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Endo T, Neville SP, Lassonde P, Qu C, Fujise H, Fushitani M, Hishikawa A, Houston PL, Bowman JM, Légaré F, Schuurman MS, Ibrahim H. Electronic relaxation and dissociation dynamics in formaldehyde: pump wavelength dependence. Phys Chem Chem Phys 2022; 24:1779-1786. [PMID: 34985091 DOI: 10.1039/d1cp04264e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The effect of the incident UV pump wavelength on the subsequent excited state dynamics, electronic relaxation, and ultimate dissociation of formaldehyde is studied using first principles simulation and Coulomb explosion imaging (CEI) experiments. Transitions in a vibronic progression in the à ← X̃ absorption band are systematically prepared using a tunable UV source which generates pulses centered at 304, 314, 329, and 337 nm. We find, both via ab initio simulation and experimental results, that the rate of excited state decay and subsequent dissociation displays a prominent dependence on which vibronic transition in the absorption band is prepared by the pump. Our simulations predict that nonadiabatic transition rates and dissociation yields will increase by a factor of >100 as the pump wavelength is decreased from 337 to 304 nm. The experimental results and theoretical simulations are in broad agreement and both indicate that the dissociation rate plateaus rapidly after ≈2 ps following an ultrafast sub-ps rise.
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Affiliation(s)
- Tomoyuki Endo
- Centre Énergie Matériaux Télécommunications, Institut National de la Recherche Scientifique, 1650 Boulevard Lionel-Boulet, Varennes, QC J3X 1S2, Canada. .,Kansai Photon Science Institute, National Institutes for Quantum Science and Technology, Umemidai, Kizugawa, Kyoto 619-0215, Japan.
| | - Simon P Neville
- National Research Council Canada, 100 Sussex Drive, Ottawa, ON K1A 0R6, Canada
| | - Philippe Lassonde
- Centre Énergie Matériaux Télécommunications, Institut National de la Recherche Scientifique, 1650 Boulevard Lionel-Boulet, Varennes, QC J3X 1S2, Canada.
| | - Chen Qu
- Department of Chemistry & Biochemistry, University of Maryland, College Park, Maryland 20742, USA
| | - Hikaru Fujise
- Department of Chemistry, Graduate School of Science, Nagoya University, Nagoya, Aichi 464-8602, Japan
| | - Mizuho Fushitani
- Department of Chemistry, Graduate School of Science, Nagoya University, Nagoya, Aichi 464-8602, Japan
| | - Akiyoshi Hishikawa
- Department of Chemistry, Graduate School of Science, Nagoya University, Nagoya, Aichi 464-8602, Japan.,Research Center for Materials Science, Nagoya University, Nagoya, Aichi 464-8602, Japan
| | - Paul L Houston
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14852, USA.,School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | - Joel M Bowman
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, USA
| | - François Légaré
- Centre Énergie Matériaux Télécommunications, Institut National de la Recherche Scientifique, 1650 Boulevard Lionel-Boulet, Varennes, QC J3X 1S2, Canada.
| | - Michael S Schuurman
- National Research Council Canada, 100 Sussex Drive, Ottawa, ON K1A 0R6, Canada.,Department of Chemistry and Biomolecular Sciences, University of Ottawa, 10 Marie Curie, Ottawa, ON K1N 6N5, Canada.
| | - Heide Ibrahim
- Centre Énergie Matériaux Télécommunications, Institut National de la Recherche Scientifique, 1650 Boulevard Lionel-Boulet, Varennes, QC J3X 1S2, Canada.
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5
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Foley CD, Xie C, Guo H, Suits A. Quantum resonances and roaming dynamics in formaldehyde photodissociation. Faraday Discuss 2022; 238:249-265. [DOI: 10.1039/d2fd00050d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The unimolecular dissociation of formaldehyde is studied via excitation to the à band at several excitation energies from just below the ground state radical dissociation threshold to 5000 cm-1 above...
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6
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Foley CD, Xie C, Guo H, Suits AG. Orbiting resonances in formaldehyde reveal coupling of roaming, radical, and molecular channels. Science 2021; 374:1122-1127. [PMID: 34822294 DOI: 10.1126/science.abk0634] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
[Figure: see text].
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Affiliation(s)
- Casey D Foley
- Department of Chemistry, University of Missouri, Columbia, MO 65211, USA
| | - Changjian Xie
- Institute of Modern Physics, Shaanxi Key Laboratory for Theoretical Physics Frontiers, Northwest University, Xian, Shaanxi 710127, China.,Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, NM 87131, USA
| | - Hua Guo
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, NM 87131, USA
| | - Arthur G Suits
- Department of Chemistry, University of Missouri, Columbia, MO 65211, USA
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7
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Xie C, Guan Y, Yarkony DR, Guo H. Vibrational energy levels of the S0 and S1 states of formaldehyde using an accurate ab initio based global diabatic potential energy matrix. Mol Phys 2021. [DOI: 10.1080/00268976.2021.1918775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Changjian Xie
- Institute of Modern Physics, Northwest University, Xi’an, Shaanxi, People’s Republic of China
| | - Yafu Guan
- Department of Chemistry, Johns Hopkins University, Baltimore, MD, USA
| | - David R. Yarkony
- Department of Chemistry, Johns Hopkins University, Baltimore, MD, USA
| | - Hua Guo
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, NM, USA
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8
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Analysis of the roaming trajectories from the dynamic and kinematic perspectives – A representative study of triatomic systems. Chem Phys Lett 2021. [DOI: 10.1016/j.cplett.2021.138599] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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9
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Palazzetti F, Tsai PY. Photodissociation Dynamics of CO-Forming Channels on the Ground-State Surface of Methyl Formate at 248 nm: Direct Dynamics Study and Assessment of Generalized Multicenter Impulsive Models. J Phys Chem A 2021; 125:1198-1220. [PMID: 33507759 DOI: 10.1021/acs.jpca.0c10464] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The photodissociation dynamics of methyl formate in the electronic ground state S0, initiated by a 248 nm-wavelength laser, is studied by direct dynamics simulations. We analyze five channels, where four of them have as products CH3OH + CO, one leading to the formation of three fragments, H2CO + H2 + CO, and a channel characterized by a roaming transition state. The analysis of energy distribution among the degrees of freedom of the product and the comparison with experimental results previously published by other groups provide the ingredients to distinguish the examined dissociation pathways. The interpretation of the results proves that the characterization of dissociation mechanisms must rely on a dynamics approach involving multiple electronic states, including considerations on the features of the S1/S0 conical intersection. Here, we also assess the generalized multicenter impulsive model, GMCIM, that has been designed for dissociation processes with exit barriers, and the energy distribution in the products is predicted on the basis of information from the saddle points and the intrinsic reaction coordinates. Main features, advantages, limits, and future perspectives of the method are reported and discussed.
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Affiliation(s)
- Federico Palazzetti
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, Perugia 06123, Italy
| | - Po-Yu Tsai
- Department of Chemistry, National Chung Hsing University, Taichung 402, Taiwan
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10
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Endo T, Neville SP, Wanie V, Beaulieu S, Qu C, Deschamps J, Lassonde P, Schmidt BE, Fujise H, Fushitani M, Hishikawa A, Houston PL, Bowman JM, Schuurman MS, Légaré F, Ibrahim H. Capturing roaming molecular fragments in real time. Science 2020; 370:1072-1077. [DOI: 10.1126/science.abc2960] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 09/16/2020] [Accepted: 10/23/2020] [Indexed: 12/20/2022]
Affiliation(s)
- Tomoyuki Endo
- Centre Énergie Matériaux Télécommunications, Institut National de la Recherche Scientifique, Varennes, Quebec J3X 1S2, Canada
- Kansai Photon Science Institute, National Institutes for Quantum and Radiological Science and Technology, Kizugawa, Kyoto 619-0215, Japan
| | - Simon P. Neville
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - Vincent Wanie
- Centre Énergie Matériaux Télécommunications, Institut National de la Recherche Scientifique, Varennes, Quebec J3X 1S2, Canada
| | - Samuel Beaulieu
- Centre Énergie Matériaux Télécommunications, Institut National de la Recherche Scientifique, Varennes, Quebec J3X 1S2, Canada
| | - Chen Qu
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA
| | - Jude Deschamps
- Centre Énergie Matériaux Télécommunications, Institut National de la Recherche Scientifique, Varennes, Quebec J3X 1S2, Canada
| | - Philippe Lassonde
- Centre Énergie Matériaux Télécommunications, Institut National de la Recherche Scientifique, Varennes, Quebec J3X 1S2, Canada
| | | | - Hikaru Fujise
- Department of Chemistry, Graduate School of Science, Nagoya University, Nagoya, Aichi 464-8602, Japan
| | - Mizuho Fushitani
- Department of Chemistry, Graduate School of Science, Nagoya University, Nagoya, Aichi 464-8602, Japan
| | - Akiyoshi Hishikawa
- Department of Chemistry, Graduate School of Science, Nagoya University, Nagoya, Aichi 464-8602, Japan
- Research Center for Materials Science, Nagoya University, Nagoya, Aichi 464-8602, Japan
| | - Paul L. Houston
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14852, USA
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Joel M. Bowman
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, GA 30322, USA
| | - Michael S. Schuurman
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
- National Research Council of Canada, Ottawa, Ontario K1A 0R6, Canada
| | - François Légaré
- Centre Énergie Matériaux Télécommunications, Institut National de la Recherche Scientifique, Varennes, Quebec J3X 1S2, Canada
| | - Heide Ibrahim
- Centre Énergie Matériaux Télécommunications, Institut National de la Recherche Scientifique, Varennes, Quebec J3X 1S2, Canada
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11
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Quinn MS, Nauta K, Jordan MJT, Bowman JM, Houston PL, Kable SH. Rotational resonances in the H
2
CO roaming reaction are revealed by detailed correlations. Science 2020; 369:1592-1596. [DOI: 10.1126/science.abc4088] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 07/19/2020] [Indexed: 11/03/2022]
Affiliation(s)
- Mitchell S. Quinn
- School of Chemistry, University of New South Wales, Kensington, NSW, 2052, Australia
| | - Klaas Nauta
- School of Chemistry, University of New South Wales, Kensington, NSW, 2052, Australia
| | | | - Joel M. Bowman
- Department of Chemistry, Emory University, Atlanta, GA, USA
| | - Paul L. Houston
- Department of Chemistry and Biochemistry, Cornell University, Ithaca, NY, USA
| | - Scott H. Kable
- School of Chemistry, University of New South Wales, Kensington, NSW, 2052, Australia
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12
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Abstract
Roaming reactions were first clearly identified in photodissociation of formaldehyde 15 years ago, and roaming dynamics are now recognized as a universal aspect of chemical reactivity. These reactions typically involve frustrated near-dissociation of a quasibound system to radical fragments, followed by reorientation at long range and intramolecular abstraction. The consequences can be unexpected formation of molecular products, depletion of the radical pool in chemical systems, and formation of products with unusual internal state distributions. In this review, I examine some current aspects of roaming reactions with an emphasis on experimental results, focusing on possible quantum effects in roaming and roaming dynamics in bimolecular systems. These considerations lead to a more inclusive definition of roaming reactions as those for which key dynamics take place at long range.
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Affiliation(s)
- Arthur G. Suits
- Department of Chemistry, University of Missouri, Columbia, Missouri 65211, USA
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13
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Iwamoto N, Schwartz CJ, Jochim B, Raju P K, Feizollah P, Napierala JL, Severt T, Tegegn SN, Solomon A, Zhao S, Lam H, Wangjam TN, Kumarappan V, Carnes KD, Ben-Itzhak I, Wells E. Strong-field control of H 3 + production from methanol dications: Selecting between local and extended formation mechanisms. J Chem Phys 2020; 152:054302. [PMID: 32035476 DOI: 10.1063/1.5129946] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Using the CD3OH isotopologue of methanol, the ratio of D2H+ to D3 + formation is manipulated by changing the characteristics of the intense femtosecond laser pulse. Detection of D2H+ indicates a formation process involving two hydrogen atoms from the methyl side of the molecule and a proton from the hydroxyl side, while detection of D3 + indicates local formation involving only the methyl group. Both mechanisms are thought to involve a neutral D2 moiety. An adaptive control strategy that employs image-based feedback to guide the learning algorithm results in an enhancement of the D2H+/D3 + ratio by a factor of approximately two. The optimized pulses have secondary structures 110-210 fs after the main pulse and result in photofragments that have different kinetic energy release distributions than those produced from near transform limited pulses. Systematic changes to the linear chirp and higher order dispersion terms of the laser pulse are compared to the results obtained with the optimized pulse shapes.
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Affiliation(s)
- Naoki Iwamoto
- Department of Physics, Augustana University, Sioux Falls, South Dakota 57197, USA
| | - Charles J Schwartz
- Department of Physics, Augustana University, Sioux Falls, South Dakota 57197, USA
| | - Bethany Jochim
- J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506, USA
| | - Kanaka Raju P
- J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506, USA
| | - Peyman Feizollah
- J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506, USA
| | - J L Napierala
- Department of Physics, Augustana University, Sioux Falls, South Dakota 57197, USA
| | - T Severt
- J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506, USA
| | - S N Tegegn
- Department of Physics, Augustana University, Sioux Falls, South Dakota 57197, USA
| | - A Solomon
- Department of Physics, Augustana University, Sioux Falls, South Dakota 57197, USA
| | - S Zhao
- Department of Physics, Augustana University, Sioux Falls, South Dakota 57197, USA
| | - Huynh Lam
- J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506, USA
| | - Tomthin Nganba Wangjam
- J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506, USA
| | - V Kumarappan
- J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506, USA
| | - K D Carnes
- J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506, USA
| | - I Ben-Itzhak
- J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506, USA
| | - E Wells
- Department of Physics, Augustana University, Sioux Falls, South Dakota 57197, USA
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14
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de Castro DG, Poveda LA, Crispim LWS, Ballester MY. Quasi-Classical Trajectory Study of NH( 3∑ -) + NH( 3∑ -) Reactive Collisions. J Phys Chem A 2019; 123:9113-9122. [PMID: 31573199 DOI: 10.1021/acs.jpca.9b08278] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A full-dimension quasi-classical trajectory study of collisions between two NH radicals is presented. Interatomic interactions are represented by a previously reported global six-dimensional potential energy surface for singlet electronic state of the N2H2 system. This study suggests that the formation of N2 from the collision of two NH radicals may occur via a one-step (NH + NH → N2 + H + H) or two-step (NH + NH → N2H + H → N2 + H + H) microscopic reaction mechanism. A fast vibrational energy redistribution is observed in the four-body complex in the latter mechanism. Excitation functions are presented and discussed. A variant of the vibrational energy quantum mechanical threshold method was used to correct the zero-point energy leakage in the classical calculations. The influence of reactant's rotational and vibrational energy on reactivity was investigated by state-specific calculations with one or both reactants excited. Reaction rate constants for the ground and some rotationally excited states are presented using an Arrhenius-Kooij-like functional form.
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Affiliation(s)
| | - Luis A Poveda
- Centro Federal de Educação Tecnológica de Minas Gerais , Belo Horizonte 36700-000 , MG , Brazil
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15
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Keshavarz F. Chemical Kinetics Approves the Occurrence of C ( 3P j) Reaction with H 2O. J Phys Chem A 2019; 123:5877-5892. [PMID: 31268710 DOI: 10.1021/acs.jpca.9b03492] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Although both atomic carbon and water are omnipresent in human life, there is a debate about the possibility of carbon reaction with water. Some low-temperature spectroscopic investigations have rejected the reaction, whereas some room-temperature experiments and theoretical studies have accepted the possibility of the reaction by reporting rate coefficients ranging from 105 to 109 L mol-1 s-1. This study provides new lines of evidence about the reaction through exploration of the reaction mechanism using the CCSD(T) method and solving the corresponding master equation by following two main approaches. According to the results, the rate coefficient of the reaction is significantly influenced by the tunneling and hindered rotation effects, in addition to the selected total angular momentum (J). Furthermore, the total rate coefficient of the reaction increases dramatically (from 107 to 1011 L mol-1 s-1) with the rise of temperature from 100 to 4000 K, while the total rate coefficient is insensitive to pressure (0.1-10 atm). Despite some differences between the results of the two approaches, the rate coefficients of both methods are consistent with the previously reported rate coefficients. Also, in agreement with the previous studies, the major products are 2HOC + 2H and 2HCO + 2H. In general, the findings approve the occurrence of the title reaction and indicate that the mentioned conflict is due to the sensitivity of the reaction to the investigated temperature and J level. The sensitivity does not permit low-temperature spectroscopic studies to detect any products and varies the measured and calculated rate coefficients.
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Affiliation(s)
- Fatemeh Keshavarz
- Department of Chemistry, College of Science , Shiraz University , Shiraz 71946-84795 , Iran
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16
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Cascarini FJJ, Hornung B, Quinn MS, Robertson PA, Orr-Ewing AJ. Collision Energy Dependence of the Competing Mechanisms of Reaction of Chlorine Atoms with Propene. J Phys Chem A 2019; 123:2679-2686. [DOI: 10.1021/acs.jpca.9b01370] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Balázs Hornung
- School of Chemistry, University of Bristol, Cantock’s
Close, Bristol BS8 1TS, United Kingdom
| | - Mitchell S. Quinn
- School of Chemistry, University of Bristol, Cantock’s
Close, Bristol BS8 1TS, United Kingdom
| | - Patrick A. Robertson
- School of Chemistry, University of Bristol, Cantock’s
Close, Bristol BS8 1TS, United Kingdom
| | - Andrew J. Orr-Ewing
- School of Chemistry, University of Bristol, Cantock’s
Close, Bristol BS8 1TS, United Kingdom
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17
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Asatryan R, Hudzik JM, Bozzelli JW, Khachatryan L, Ruckenstein E. OH-Initiated Reactions of p-Coumaryl Alcohol Relevant to the Lignin Pyrolysis. Part I. Potential Energy Surface Analysis. J Phys Chem A 2019; 123:2570-2585. [DOI: 10.1021/acs.jpca.9b00185] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Rubik Asatryan
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Buffalo, New York 14226, United States
| | - Jason M. Hudzik
- Department of Chemistry and Environmental Science, New Jersey Institute of Technology, Newark, New Jersey 07102, United States
| | - Joseph W. Bozzelli
- Department of Chemistry and Environmental Science, New Jersey Institute of Technology, Newark, New Jersey 07102, United States
| | - Lavrent Khachatryan
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Eli Ruckenstein
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Buffalo, New York 14226, United States
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18
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Asatryan R, Pal Y, Hachmann J, Ruckenstein E. Roaming-like Mechanism for Dehydration of Diol Radicals. J Phys Chem A 2018; 122:9738-9754. [DOI: 10.1021/acs.jpca.8b08690] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Rubik Asatryan
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Buffalo, New York 14260, United States
| | - Yudhajit Pal
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Buffalo, New York 14260, United States
- Computational and Data-Enabled Science and Engineering Graduate Program, University at Buffalo, The State University of New York, Buffalo, New York 14260, United States
| | - Johannes Hachmann
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Buffalo, New York 14260, United States
- New York State Center of Excellence in Materials Informatics, Buffalo, New York 14203, United States
- Computational and Data-Enabled Science and Engineering Graduate Program, University at Buffalo, The State University of New York, Buffalo, New York 14260, United States
| | - Eli Ruckenstein
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Buffalo, New York 14260, United States
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19
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Krajňák V, Wiggins S. Influence of mass and potential energy surface geometry on roaming in Chesnavich's CH4+ model. J Chem Phys 2018; 149:094109. [PMID: 30195292 DOI: 10.1063/1.5044532] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Chesnavich's model Hamiltonian for the reaction CH4+→ CH3+ + H is known to exhibit a range of interesting dynamical phenomena including roaming. The model system consists of two parts: a rigid, symmetric top representing the CH3+ ion and a free H atom. We study roaming in this model with focus on the evolution of geometrical features of the invariant manifolds in phase space that govern roaming under variations of the mass of the free atom m and a parameter a that couples radial and angular motion. In addition, we establish an upper bound on the prominence of roaming in Chesnavich's model. The bound highlights the intricacy of roaming as a type of dynamics on the verge between isomerisation and nonreactivity as it relies on generous access to the potential wells to allow reactions as well as a prominent area of high potential that aids sufficient transfer of energy between the degrees of freedom to prevent isomerisation.
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Affiliation(s)
- Vladimír Krajňák
- School of Mathematics, University of Bristol, Bristol BS8 1TW, United Kingdom
| | - Stephen Wiggins
- School of Mathematics, University of Bristol, Bristol BS8 1TW, United Kingdom
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20
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Lin KC, Tsai PY, Chao MH, Nakamura M, Kasai T, Lombardi A, Palazzetti F, Aquilanti V. Roaming signature in photodissociation of carbonyl compounds. INT REV PHYS CHEM 2018. [DOI: 10.1080/0144235x.2018.1488951] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- King-Chuen Lin
- Department of Chemistry, National Taiwan University, Taipei, Taiwan (ROC)
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan (ROC)
| | - Po-Yu Tsai
- Department of Chemistry, National Chung-Hsing University, Taichung, Taiwan (ROC)
| | - Meng-Hsuan Chao
- Department of Chemistry, National Taiwan University, Taipei, Taiwan (ROC)
| | - Masaaki Nakamura
- Department of Chemistry, National Taiwan University, Taipei, Taiwan (ROC)
| | - Toshio Kasai
- Department of Chemistry, National Taiwan University, Taipei, Taiwan (ROC)
- Institute of Scientific and Industrial Research, Osaka University, Osaka, Japan
| | - Andrea Lombardi
- Dipartimento di Chimica, Biologia e Biotecnologie, Università di Perugia, Perugia, Italy
- Consortium for Computational Molecular and Materials Sciences (CMS)2, Perugia, Italy
| | - Federico Palazzetti
- Dipartimento di Chimica, Biologia e Biotecnologie, Università di Perugia, Perugia, Italy
- Scuola Normale Superiore di Pisa, Pisa, Italy
| | - Vincenzo Aquilanti
- Dipartimento di Chimica, Biologia e Biotecnologie, Università di Perugia, Perugia, Italy
- Istituto di Struttura della Materia, Consiglio Nazionale delle Ricerche, Rome, Italy
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21
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Tsai PY. A generalized unimolecular impulsive model for curved reaction path. J Chem Phys 2018; 148:234101. [PMID: 29935512 DOI: 10.1063/1.5030488] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
This work aims to introduce a generalized impulsive model for unimolecular dissociation processes. This model allows us to take into account the curvature of the reaction path explicitly. It is a generalization of the previously developed multi-center impulsive model [P.-Y. Tsai and K.-C. Lin, J. Phys. Chem. A 119, 29 (2015)]. Several limitations of conventional impulsive models are eliminated by this study: (1) Unlike conventional impulsive models, in which a single molecular geometry is responsible for the impulse determination, the gradients on the whole dissociation path are taken into account. The model can treat dissociation pathways with large curvatures and loose saddle points. (2) The method can describe the vibrational excitation of polyatomic fragments due to the bond formation by multi-center impulse. (3) The available energy in conventional impulsive models is separated into uncoupled statistical and impulsive energy reservoirs, while the interplay between these reservoirs is allowed in the new model. (4) The quantum state correlation between fragments can be preserved in analysis. Dissociations of several molecular systems including the roaming pathways of formaldehyde, nitrate radical, acetaldehyde, and glyoxal are chosen as benchmarks. The predicted photofragment energy and vector distributions are consistent with the experimental results reported previously. In these examples, the capability of the new model to treat the curved dissociation path, loose saddle points, polyatomic fragments, and multiple-body dissociation is verified. As a cheaper computational tool with respect to ab initio on-the-fly direct dynamic simulations, this model can provide detailed information on the energy disposal, quantum state correlation, and stereodynamics in unimolecular dissociation processes.
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Affiliation(s)
- Po-Yu Tsai
- Department of Chemistry, National Chung Hsing University, Taichung 402, Taiwan
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22
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Di Liberto G, Conte R, Ceotto M. "Divide and conquer" semiclassical molecular dynamics: A practical method for spectroscopic calculations of high dimensional molecular systems. J Chem Phys 2018; 148:014307. [PMID: 29306274 DOI: 10.1063/1.5010388] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
We extensively describe our recently established "divide-and-conquer" semiclassical method [M. Ceotto, G. Di Liberto, and R. Conte, Phys. Rev. Lett. 119, 010401 (2017)] and propose a new implementation of it to increase the accuracy of results. The technique permits us to perform spectroscopic calculations of high-dimensional systems by dividing the full-dimensional problem into a set of smaller dimensional ones. The partition procedure, originally based on a dynamical analysis of the Hessian matrix, is here more rigorously achieved through a hierarchical subspace-separation criterion based on Liouville's theorem. Comparisons of calculated vibrational frequencies to exact quantum ones for a set of molecules including benzene show that the new implementation performs better than the original one and that, on average, the loss in accuracy with respect to full-dimensional semiclassical calculations is reduced to only 10 wavenumbers. Furthermore, by investigating the challenging Zundel cation, we also demonstrate that the "divide-and-conquer" approach allows us to deal with complex strongly anharmonic molecular systems. Overall the method very much helps the assignment and physical interpretation of experimental IR spectra by providing accurate vibrational fundamentals and overtones decomposed into reduced dimensionality spectra.
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Affiliation(s)
- Giovanni Di Liberto
- Dipartimento di Chimica, Università degli Studi di Milano, Via C. Golgi 19, 20133 Milano, Italy
| | - Riccardo Conte
- Dipartimento di Chimica, Università degli Studi di Milano, Via C. Golgi 19, 20133 Milano, Italy
| | - Michele Ceotto
- Dipartimento di Chimica, Università degli Studi di Milano, Via C. Golgi 19, 20133 Milano, Italy
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23
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Cofer-Shabica DV, Stratt RM. What is special about how roaming chemical reactions traverse their potential surfaces? Differences in geodesic paths between roaming and non-roaming events. J Chem Phys 2018; 146:214303. [PMID: 28595418 DOI: 10.1063/1.4984617] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
With the notable exception of some illustrative two-degree-of-freedom models whose surprising classical dynamics has been worked out in detail, theories of roaming have largely bypassed the issue of when and why the counterintuitive phenomenon of roaming occurs. We propose that a useful way to begin to address these issues is to look for the geodesic (most efficient) pathways through the potential surfaces of candidate systems. Although roaming manifests itself in an unusual behavior at asymptotic geometries, we found in the case of formaldehyde dissociation that it was the pathways traversing the parts of the potential surface corresponding to highly vibrationally excited reactants that were the most revealing. An examination of the geodesics for roaming pathways in this region finds that they are much less tightly defined than the geodesics in that same region that lead directly to dissociation (whether into closed-shell products or into radical products). Thus, the broader set of options available to the roaming channel gives it an entropic advantage over more conventional reaction channels. These observations suggest that what leads to roaming in other systems may be less the presence of a localized "roaming transition state," than the existence of an entire region of the potential surface conducive to multiple equivalent pathways.
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Affiliation(s)
| | - Richard M Stratt
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA
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24
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Lee KLK, Quinn MS, Kolmann SJ, Kable SH, Jordan MJT. Zero-point energy conservation in classical trajectory simulations: Application to H2CO. J Chem Phys 2018; 148:194113. [DOI: 10.1063/1.5023508] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
| | - Mitchell S. Quinn
- School of Chemistry, The University of Sydney, Sydney, NSW 2006, Australia
- School of Chemistry, The University of New South Wales, Sydney, NSW 2052, Australia
| | - Stephen J. Kolmann
- School of Chemistry, The University of Sydney, Sydney, NSW 2006, Australia
| | - Scott H. Kable
- School of Chemistry, The University of New South Wales, Sydney, NSW 2052, Australia
| | - Meredith J. T. Jordan
- School of Chemistry, The University of Sydney, Sydney, NSW 2006, Australia
- School of Chemistry, The University of New South Wales, Sydney, NSW 2052, Australia
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25
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Buchholz M, Grossmann F, Ceotto M. Simplified approach to the mixed time-averaging semiclassical initial value representation for the calculation of dense vibrational spectra. J Chem Phys 2018; 148:114107. [DOI: 10.1063/1.5020144] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Max Buchholz
- Dipartimento di Chimica, Università degli Studi di Milano, Via C. Golgi 19, 20133 Milano, Italy
| | - Frank Grossmann
- Institut für Theoretische Physik, Technische Universität Dresden, 01062 Dresden, Germany
| | - Michele Ceotto
- Dipartimento di Chimica, Università degli Studi di Milano, Via C. Golgi 19, 20133 Milano, Italy
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26
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Di Liberto G, Conte R, Ceotto M. “Divide-and-conquer” semiclassical molecular dynamics: An application to water clusters. J Chem Phys 2018; 148:104302. [DOI: 10.1063/1.5023155] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Giovanni Di Liberto
- Dipartimento di Chimica, Università degli Studi di Milano, Via C. Golgi 19, 20133 Milano, Italy
| | - Riccardo Conte
- Dipartimento di Chimica, Università degli Studi di Milano, Via C. Golgi 19, 20133 Milano, Italy
| | - Michele Ceotto
- Dipartimento di Chimica, Università degli Studi di Milano, Via C. Golgi 19, 20133 Milano, Italy
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27
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Krajňák V, Waalkens H. The phase space geometry underlying roaming reaction dynamics. JOURNAL OF MATHEMATICAL CHEMISTRY 2018; 56:2341-2378. [PMID: 30956381 PMCID: PMC6428411 DOI: 10.1007/s10910-018-0895-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 01/23/2018] [Indexed: 06/09/2023]
Abstract
Recent studies have found an unusual way of dissociation in formaldehyde. It can be characterized by a hydrogen atom that separates from the molecule, but instead of dissociating immediately it roams around the molecule for a considerable amount of time and extracts another hydrogen atom from the molecule prior to dissociation. This phenomenon has been coined roaming and has since been reported in the dissociation of a number of other molecules. In this paper we investigate roaming in Chesnavich's CH 4 + model. During dissociation the free hydrogen must pass through three phase space bottleneck for the classical motion, that can be shown to exist due to unstable periodic orbits. None of these orbits is associated with saddle points of the potential energy surface and hence related to transition states in the usual sense. We explain how the intricate phase space geometry influences the shape and intersections of invariant manifolds that form separatrices, and establish the impact of these phase space structures on residence times and rotation numbers. Ultimately we use this knowledge to attribute the roaming phenomenon to particular heteroclinic intersections.
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Affiliation(s)
- Vladimír Krajňák
- Johann Bernoulli Institute, University of Groningen, Nijenborgh 9, 9747 AG Groningen, The Netherlands
- Present Address: School of Mathematics, University of Bristol, University Walk, Bristol, BS8 1TW UK
| | - Holger Waalkens
- Johann Bernoulli Institute, University of Groningen, Nijenborgh 9, 9747 AG Groningen, The Netherlands
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28
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Abstract
The phenomenon of roaming in chemical reactions has now become both commonly observed in experiment and extensively supported by theory and simulations. Roaming occurs in highly-excited molecules when the trajectories of atomic motion often bypass the minimum energy pathway and produce reaction in unexpected ways from unlikely geometries. The prototypical example is the unimolecular dissociation of formaldehyde (H2CO), in which the "normal" reaction proceeds through a tight transition state to yield H2 + CO but for which a high fraction of dissociations take place via a "roaming" mechanism in which one H atom moves far from the HCO, almost to dissociation, and then returns to abstract the second H atom. We review below the theories and simulations that have recently been developed to address and understand this new reaction phenomenon.
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Affiliation(s)
- Joel M Bowman
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University Atlanta, Georgia 30322, USA.
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29
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Kuwata KT, Luu L, Weberg AB, Huang K, Parsons AJ, Peebles LA, Rackstraw NB, Kim MJ. Quantum Chemical and Statistical Rate Theory Studies of the Vinyl Hydroperoxides Formed in trans-2-Butene and 2,3-Dimethyl-2-butene Ozonolysis. J Phys Chem A 2018; 122:2485-2502. [DOI: 10.1021/acs.jpca.8b00287] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Keith T. Kuwata
- Department of Chemistry, Macalester College, Saint Paul, Minnesota 55105-1899, United States
| | - Lina Luu
- Department of Chemistry, Macalester College, Saint Paul, Minnesota 55105-1899, United States
| | - Alexander B. Weberg
- Department of Chemistry, Macalester College, Saint Paul, Minnesota 55105-1899, United States
| | - Ke Huang
- Department of Chemistry, Macalester College, Saint Paul, Minnesota 55105-1899, United States
| | - Austin J. Parsons
- Department of Chemistry, Macalester College, Saint Paul, Minnesota 55105-1899, United States
| | - Liam A. Peebles
- Department of Chemistry, Macalester College, Saint Paul, Minnesota 55105-1899, United States
| | - Nathan B. Rackstraw
- Department of Chemistry, Macalester College, Saint Paul, Minnesota 55105-1899, United States
| | - Min Ji Kim
- Department of Chemistry, Macalester College, Saint Paul, Minnesota 55105-1899, United States
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30
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Kaiser EW, Wallington TJ. Products from the Oxidation of n-Butane from 298 to 735 K Using Either Cl Atom or Thermal Initiation: Formation of Acetone and Acetic Acid-Possible Roaming Reactions? J Phys Chem A 2017; 121:8543-8560. [PMID: 28982240 DOI: 10.1021/acs.jpca.7b06608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The oxidation of 2-butyl radicals (and to a lesser extent 1-butyl radicals) has been studied over the temperature range of 298-735 K. The reaction of Cl atoms (formed by 360 nm irradiation of Cl2) with n-butane generated the 2-butyl radicals in mixtures of n-C4H10, O2, and Cl2 at temperatures below 600 K. Above 600 K, 2-butyl radicals were produced by thermal combustion reactions in the absence of chlorine. The yields of the products were measured by gas chromatography using a flame ionization detector. Major products quantified include acetone, acetic acid, acetaldehyde, butanone, 2-butanol, butanal, 1- and 2- chlorobutane, 1-butene, trans-2-butene, and cis-2-butene. At 298 K, the major oxygenated products are those expected from bimolecular reactions of 2-butylperoxy radicals (butanone, 2-butanol, and acetaldehyde). As the temperature rises to 390 K, the butanone decreases while acetaldehyde increases because of the increased rate of 2-butoxy radical decomposition. Acetone and acetic acid first appear in significant yield near 400 K, and these species rise slowly at first and then sharply, peaking near 525 K at yields of ∼25 and ∼20 mol %, respectively. In the same temperature range (400-525 K), butanone, acetaldehyde, and 2-butanol decrease rapidly. This suggests that acetone and acetic acid may be formed by previously unknown reaction channels of the 2-butylperoxy radical, which are in competition with those that lead to butanone, acetaldehyde, and 2-butanol. Above 570 K, the yields of acetone and acetic acid fall rapidly as the yields of the butenes rise. Experiments varying the Cl atom density, which in turn controls the entire radical pool density, were performed in the temperature range of 410-440 K. Decreasing the Cl atom density increased the yields of acetone and acetic acid while the yields of butanone, acetaldehyde, and 2-butanol decreased. This is consistent with the formation of acetone and acetic acid by unimolecular decomposition channels of the 2-butylperoxy radical, which are in competition with the bimolecular channels that form butanone, acetaldehyde, and 2-butanol. Such unimolecular decomposition channels would be unlikely to proceed through conventional transition states because those states would be very constrained. Therefore, the possibility that these decomposition channels proceed via roaming should be considered. In addition, we investigated and were unable to fit our data trends by a simplified ketohydroperoxide mechanism.
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Affiliation(s)
- E W Kaiser
- Department of Natural Sciences, University of Michigan-Dearborn , 4901 Evergreen Road, Dearborn, Michigan 48128, United States
| | - T J Wallington
- Research and Advanced Engineering, Ford Motor Company , Dearborn, Michigan 48121-2053, United States
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31
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Houston PL, Wang X, Ghosh A, Bowman JM, Quinn MS, Kable SH. Formaldehyde roaming dynamics: Comparison of quasi-classical trajectory calculations and experiments. J Chem Phys 2017; 147:013936. [DOI: 10.1063/1.4982823] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Paul L. Houston
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, USA and Department of Chemistry and Chemical Biology, Cornell University, Baker Laboratory, Ithaca, New York 14852, USA
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, USA
| | - Xiaohong Wang
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, USA
| | - Aryya Ghosh
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, USA
| | - Joel M. Bowman
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, USA
| | - Mitchell S. Quinn
- School of Chemistry, The University of New South Wales, Sydney, NSW 2052, Australia
| | - Scott H. Kable
- School of Chemistry, The University of New South Wales, Sydney, NSW 2052, Australia
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32
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Ceotto M, Di Liberto G, Conte R. Semiclassical "Divide-and-Conquer" Method for Spectroscopic Calculations of High Dimensional Molecular Systems. PHYSICAL REVIEW LETTERS 2017; 119:010401. [PMID: 28731742 DOI: 10.1103/physrevlett.119.010401] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Indexed: 05/11/2023]
Abstract
A new semiclassical "divide-and-conquer" method is presented with the aim of demonstrating that quantum dynamics simulations of high dimensional molecular systems are doable. The method is first tested by calculating the quantum vibrational power spectra of water, methane, and benzene-three molecules of increasing dimensionality for which benchmark quantum results are available-and then applied to C_{60}, a system characterized by 174 vibrational degrees of freedom. Results show that the approach can accurately account for quantum anharmonicities, purely quantum features like overtones, and the removal of degeneracy when the molecular symmetry is broken.
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Affiliation(s)
- Michele Ceotto
- Dipartimento di Chimica, Università degli Studi di Milano, via C. Golgi 19, 20133 Milano, Italy
| | - Giovanni Di Liberto
- Dipartimento di Chimica, Università degli Studi di Milano, via C. Golgi 19, 20133 Milano, Italy
| | - Riccardo Conte
- Dipartimento di Chimica, Università degli Studi di Milano, via C. Golgi 19, 20133 Milano, Italy
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33
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Quinn MS, Andrews DU, Nauta K, Jordan MJT, Kable SH. The energy dependence of CO(v,J) produced from H2CO via the transition state, roaming, and triple fragmentation channels. J Chem Phys 2017; 147:013935. [DOI: 10.1063/1.4983138] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Mitchell S. Quinn
- School of Chemistry, The University of New South Wales, Sydney, NSW 2052, Australia
| | - Duncan U. Andrews
- School of Chemistry, The University of Sydney, Sydney, NSW 2006, Australia
| | - Klaas Nauta
- School of Chemistry, The University of New South Wales, Sydney, NSW 2052, Australia
| | | | - Scott H. Kable
- School of Chemistry, The University of New South Wales, Sydney, NSW 2052, Australia
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34
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Aieta C, Ceotto M. A quantum method for thermal rate constant calculations from stationary phase approximation of the thermal flux-flux correlation function integral. J Chem Phys 2017; 146:214115. [DOI: 10.1063/1.4984099] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Chiara Aieta
- Dipartimento di Chimica, Università degli Studi di Milano, Via C. Golgi 19, 20133 Milano, Italy
| | - Michele Ceotto
- Dipartimento di Chimica, Università degli Studi di Milano, Via C. Golgi 19, 20133 Milano, Italy
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35
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Mauguière FA, Collins P, Kramer ZC, Carpenter BK, Ezra GS, Farantos SC, Wiggins S. Roaming: A Phase Space Perspective. Annu Rev Phys Chem 2017; 68:499-524. [DOI: 10.1146/annurev-physchem-052516-050613] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
| | - Peter Collins
- School of Mathematics, University of Bristol, Bristol BS8 1TW, United Kingdom;, ,
| | - Zeb C. Kramer
- Department of Chemistry and Biochemistry, La Salle University, Philadelphia, Pennsylvania 19141
| | - Barry K. Carpenter
- School of Chemistry, Cardiff University, Cardiff CF10 3AT, United Kingdom
| | - Gregory S. Ezra
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853
| | - Stavros C. Farantos
- Department of Chemistry, University of Crete, Heraklion 700 13, Greece
- Institute of Electronic Structure and Laser, Foundation for Research and Technology—Hellas, Heraklion 711 10, Greece
| | - Stephen Wiggins
- School of Mathematics, University of Bristol, Bristol BS8 1TW, United Kingdom;, ,
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36
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Ma X, Hase WL. Perspective: chemical dynamics simulations of non-statistical reaction dynamics. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2017; 375:rsta.2016.0204. [PMID: 28320906 PMCID: PMC5360902 DOI: 10.1098/rsta.2016.0204] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 01/05/2017] [Indexed: 06/06/2023]
Abstract
Non-statistical chemical dynamics are exemplified by disagreements with the transition state (TS), RRKM and phase space theories of chemical kinetics and dynamics. The intrinsic reaction coordinate (IRC) is often used for the former two theories, and non-statistical dynamics arising from non-IRC dynamics are often important. In this perspective, non-statistical dynamics are discussed for chemical reactions, with results primarily obtained from chemical dynamics simulations and to a lesser extent from experiment. The non-statistical dynamical properties discussed are: post-TS dynamics, including potential energy surface bifurcations, product energy partitioning in unimolecular dissociation and avoiding exit-channel potential energy minima; non-RRKM unimolecular decomposition; non-IRC dynamics; direct mechanisms for bimolecular reactions with pre- and/or post-reaction potential energy minima; non-TS theory barrier recrossings; and roaming dynamics.This article is part of the themed issue 'Theoretical and computational studies of non-equilibrium and non-statistical dynamics in the gas phase, in the condensed phase and at interfaces'.
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Affiliation(s)
- Xinyou Ma
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409, USA
| | - William L Hase
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409, USA
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37
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Sun J, Shao Y, Wu W, Tang Y, Zhang Y, Hu Y, Liu J, Yi H, Chen F, Cheng Y. A quantum chemical study on ˙Cl-initiated atmospheric degradation of acrylonitrile. RSC Adv 2017. [DOI: 10.1039/c7ra01521f] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Degradation of acrylonitrile (CH2CHCN) by reaction with atomic chlorine was studied using quantum chemical methods.
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