1
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Smith JM, Nikow M, Wilhelm MJ, Dai HL. Collisional Relaxation of Highly Vibrationally Excited Acetylene Mediated by the Vinylidene Isomer. J Phys Chem A 2023; 127:8782-8793. [PMID: 37846886 DOI: 10.1021/acs.jpca.3c03656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2023]
Abstract
Collisional relaxation of highly vibrationally excited acetylene, generated from the 193 nm photolysis of vinyl bromide with roughly 23,000 cm-1 of nascent vibrational energy, is studied via submicrosecond time-resolved Fourier transform infrared (FTIR) emission spectroscopy. IR emission from vibrationally hot acetylene during collisional relaxation by helium, neon, argon, and krypton rare-gas colliders is recorded and analyzed to deduce the acetylene energy content as a function of time. The average energy lost per collision, ⟨ΔE⟩, is computed using the Lennard-Jones collision frequency. Two distinct vibrational-to-translational (V-T) energy transfer regimes in terms of the acetylene energy are identified. At vibrational energies below 10,000-14,000 cm-1, energy transfer efficiency increases linearly with molecular energy content and is in line with typical V-T behavior in quantity. In contrast, above 10,000-14,000 cm-1, the V-T energy transfer efficiency displays a dramatic and rapid increase. This increase is nearly coincident with the acetylene-vinylidene isomerization limit, which occurs nearly 15,000 cm-1 above the acetylene zero-point energy. Combined quasi-classical trajectory calculations and Schwartz-Slawsky-Herzfeld-Tanczos theory point to a vinylidene contribution being responsible for the large enhancement. This observation illustrates the influence of energetically accessible structural isomers to greatly enhance the energy transfer rates of highly vibrationally excited molecules.
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Affiliation(s)
- Jonathan M Smith
- Department of Chemistry, Temple University, 1901 N. 13th. Street, Philadelphia, Pennsylvania 19122, United States
- Hylleraas Institute, Department of Chemistry, University of Oslo, Oslo 0313, Norway
| | - Matthew Nikow
- Department of Chemistry, Temple University, 1901 N. 13th. Street, Philadelphia, Pennsylvania 19122, United States
| | - Michael J Wilhelm
- Department of Chemistry, Temple University, 1901 N. 13th. Street, Philadelphia, Pennsylvania 19122, United States
| | - Hai-Lung Dai
- Department of Chemistry, Temple University, 1901 N. 13th. Street, Philadelphia, Pennsylvania 19122, United States
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2
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Jurado Romero A, Calero C, Sibert EL, Rey R. High energy vibrational excitations of nitromethane in liquid water. J Chem Phys 2023; 158:2890474. [PMID: 37184013 DOI: 10.1063/5.0147459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 04/28/2023] [Indexed: 05/16/2023] Open
Abstract
The pathways and timescales of vibrational energy flow in nitromethane are investigated in both gas and condensed phases using classical molecular mechanics, with a particular focus on relaxation in liquid water. We monitor the flow of excess energy deposited in vibrational modes of nitromethane into the surrounding solvent. A marked energy flux anisotropy is found when nitromethane is immersed in liquid water, with a preferential flow to those water molecules in contact to the nitro group. The factors that permit such anisotropic energy relaxation are discussed, along with the potential implications on the molecule's non-equilibrium dynamics. In addition, the energy flux analysis allows us to identify the solvent motions responsible for the uptake of solute energy, confirming the crucial role of water librations. Finally, we also show that no anisotropic vibrational energy relaxation occurs when nitromethane is surrounded by argon gas.
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Affiliation(s)
- Arnau Jurado Romero
- Departament de Física, Universitat Politècnica de Catalunya, Barcelona 08034, Spain
| | - Carles Calero
- Departament de Física de la Matèria Condensada and Institut de Nanociència i Nanotecnologia, Universitat de Barcelona, 08028 Barcelona, Spain
| | - Edwin L Sibert
- Department of Chemistry and Theoretical Chemistry Institute, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Rossend Rey
- Departament de Física, Universitat Politècnica de Catalunya, Barcelona 08034, Spain
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3
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Carpenter BK. Prediction of Kinetic Product Ratios: Investigation of a Dynamically Controlled Case. J Phys Chem A 2023; 127:224-239. [PMID: 36594780 PMCID: PMC9841574 DOI: 10.1021/acs.jpca.2c08301] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Of the various factors influencing kinetically controlled product ratios, the role of nonstatistical dynamics is arguably the least well understood. In this paper, reactions were chosen in which dynamics played a dominant role in product selection, by design. Specifically, the reactions studied were the ring openings of cyclopropylidene to allene and tetramethylcyclopropylidene to tetramethylallene (2,4-dimethylpenta-2,3-diene). Both reactions have intrinsic reaction coordinates that bifurcate symmetrically, leading to products that are enantiomeric once the atoms are uniquely labeled. The question addressed in the study was whether the outcomes─that is, which product well on the potential energy surface was selected─could be predicted from their initial conditions for individual trajectories in quasiclassical dynamics simulations. Hybrid potentials were developed based on cooperative interaction between molecular mechanics and artificial neural networks, trained against data from electronic structure calculations. These potentials allowed simulations of both gas-phase and condensed-phase reactions. The outcome was that, for both reactions, prediction of initial selection of product wells could be made with >95% success from initial conditions of the trajectories in the gas phase. However, when trajectories were run for longer, looking for "final" products for each trajectory, the predictability dropped off dramatically. In the gas-phase simulations, this drop off was caused by trajectories hopping between product wells on the potential energy surface. That behavior could be suppressed in condensed phases, but then new uncertainty was introduced because the intermolecular interactions between solute and bath, necessary to permit intermolecular energy transfer and cooling of the hot initial products, often led to perturbations of the initial directions of trajectories on the potential energy surface. It would consequently appear that a general ability to predict outcomes for reactions in which nonstatistical dynamics dominate remains a challenge even in the age of sophisticated machine-learning capabilities.
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4
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Ahamed SS, Mahanta H, Paul AK. An advanced bath model to simulate association followed by ensuing dissociation dynamics of benzene + benzene system: a comparative study of gas and condensed phase results. Phys Chem Chem Phys 2022; 24:23825-23839. [PMID: 36164966 DOI: 10.1039/d2cp02483g] [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 role of the environment (N2 molecules) on the association followed by the ensuing dissociation reaction of benzene + benzene system is studied here with the help of a new code setup. Chemical dynamics simulations are performed to investigate this reaction in vacuum as well as in a bath of 1000 N2 molecules, equilibrated at 300 K. Bath densities of 20 and 324 kg m-3 are considered with a few results from the latter density. The simulations are performed at three different excitation temperatures of benzene, namely, 1000, 1500, and 2000 K, with an impact parameter range of 0-12 Å for both vacuum and bath models. Higher association probabilities and hence, higher temperature dependent association rate constants are obtained in the condensed phase. In the condensed phase, when a trajectory takes a longer time for the monomers to associate, the associated complex is formed with a longer lifetime and provides a lower rate of ensuing dissociation. Higher association rate and lower dissociation rate in condensed phase dynamics are due to the energy transfer process. Hence, the energy transfer phenomenon plays a decisive role in the association/dissociation dynamics, which is completely ignored in the same reaction when studied in vacuum.
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Affiliation(s)
- Sk Samir Ahamed
- Department of Chemistry, National Institute of Technology Meghalaya, Shillong 793003, Meghalaya, India.
| | - Himashree Mahanta
- Department of Chemistry, National Institute of Technology Meghalaya, Shillong 793003, Meghalaya, India.
| | - Amit K Paul
- Department of Chemistry, National Institute of Technology Meghalaya, Shillong 793003, Meghalaya, India.
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5
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Jasper A. Predicting third-body collision efficiencies for water and other polyatomic baths. Faraday Discuss 2022; 238:68-86. [DOI: 10.1039/d2fd00038e] [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
Low-pressure-limit microcanonical (collisional activation) and thermal rate constants are predicted using a combination of automated ab initio potential energy surface construction, classical trajectories, transition state theory, and a detailed kinetic...
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6
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Moberg DR, Jasper AW. Permutationally Invariant Polynomial Expansions with Unrestricted Complexity. J Chem Theory Comput 2021; 17:5440-5455. [PMID: 34469127 DOI: 10.1021/acs.jctc.1c00352] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A general strategy is presented for constructing and validating permutationally invariant polynomial (PIP) expansions for chemical systems of any stoichiometry. Demonstrations are made for three categories of gas-phase dynamics and kinetics: collisional energy-transfer trajectories for predicting pressure-dependent kinetics, three-body collisions for describing transient van der Waals adducts relevant to atmospheric chemistry, and nonthermal reactivity via quasiclassical trajectories. In total, 30 systems are considered with up to 15 atoms and 39 degrees of freedom. Permutational invariance is enforced in PIP expansions with as many as 13 million terms and 13 permutationally distinct atom types by taking advantage of petascale computational resources. The quality of the PIP expansions is demonstrated through the systematic convergence of in-sample and out-of-sample errors with respect to both the number of training data and the order of the expansion, and these errors are shown to predict errors in the dynamics for both reactive and nonreactive applications. The parallelized code distributed as part of this work enables the automation of PIP generation for complex systems with multiple channels and flexible user-defined symmetry constraints and for automatically removing unphysical unconnected terms from the basis set expansions, all of which are required for simulating complex reactive systems.
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Affiliation(s)
- Daniel R Moberg
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Ahren W Jasper
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
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7
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Propensity for super energy transfer as a function of collision energy for the H + C2H2 system. Chem Phys Lett 2021. [DOI: 10.1016/j.cplett.2021.138676] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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8
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Ahamed SS, Kim H, Paul AK, West NA, Winner JD, Donzis DA, North SW, Hase WL. Comparison of intermolecular energy transfer from vibrationally excited benzene in mixed nitrogen-benzene baths at 140 K and 300 K. J Chem Phys 2020; 153:144116. [PMID: 33086796 DOI: 10.1063/5.0021293] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Gas phase intermolecular energy transfer (IET) is a fundamental component of accurately explaining the behavior of gas phase systems in which the internal energy of particular modes of molecules is greatly out of equilibrium. In this work, chemical dynamics simulations of mixed benzene/N2 baths with one highly vibrationally excited benzene molecule (Bz*) are compared to experimental results at 140 K. Two mixed bath models are considered. In one, the bath consists of 190 N2 and 10 Bz, whereas in the other bath, 396 N2 and 4 Bz are utilized. The results are compared to results from 300 K simulations and experiments, revealing that Bz*-Bz vibration-vibration IET efficiency increased at low temperatures consistent with longer lived "chattering" collisions at lower temperatures. In the simulations, at the Bz* excitation energy of 150 kcal/mol, the averaged energy transferred per collision, ⟨ΔEc⟩, for Bz*-Bz collisions is found to be ∼2.4 times larger in 140 K than in 300 K bath, whereas this value is ∼1.3 times lower for Bz*-N2 collisions. The overall ⟨ΔEc⟩, for all collisions, is found to be almost two times larger at 140 K compared to the one obtained from the 300 K bath. Such an enhancement of IET efficiency at 140 K is qualitatively consistent with the experimental observation. However, the possible reasons for not attaining a quantitative agreement are discussed. These results imply that the bath temperature and molecular composition as well as the magnitude of vibrational energy of a highly vibrationally excited molecule can shift the overall timescale of rethermalization.
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Affiliation(s)
- Sk Samir Ahamed
- Department of Chemistry, National Institute of Technology Meghalaya, Shillong 793003, India
| | - Hyunsik Kim
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409, USA
| | - Amit K Paul
- Department of Chemistry, National Institute of Technology Meghalaya, Shillong 793003, India
| | - Niclas A West
- Department of Chemistry, Texas A&M University, College Station, Texas 77842, USA
| | - Joshua D Winner
- Department of Chemistry, Texas A&M University, College Station, Texas 77842, USA
| | - Diego A Donzis
- Department of Chemistry, Texas A&M University, College Station, Texas 77842, USA
| | - Simon W North
- Department of Chemistry, Texas A&M University, College Station, Texas 77842, USA
| | - William L Hase
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409, USA
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9
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Ahamed SS, Kumar P, Kalita H, Paul AK. Mode‐to‐Mode Collision Energy Transfer from Vibrationally Excited C
6
F
6
to NO/N
2
Mixed Bath with the Development of New Potential Energy Functions. ChemistrySelect 2020. [DOI: 10.1002/slct.202002600] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Sk. Samir Ahamed
- Department of Chemistry National Institute of Technology Meghalaya Shillong Meghalaya 793003 INDIA
| | - Pavan Kumar
- Department of Chemistry National Institute of Technology Meghalaya Shillong Meghalaya 793003 INDIA
| | - Hrishikesh Kalita
- Department of Chemistry National Institute of Technology Meghalaya Shillong Meghalaya 793003 INDIA
- Department of Chemistry Indian Institute of Technology Guwahati Guwahati Assam 781039 INDIA
| | - Amit K. Paul
- Department of Chemistry National Institute of Technology Meghalaya Shillong Meghalaya 793003 INDIA
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10
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Jasper AW. “Third‐body” collision parameters for hydrocarbons, alcohols, and hydroperoxides and an effective internal rotor approach for estimating them. INT J CHEM KINET 2020. [DOI: 10.1002/kin.21358] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Ahren W. Jasper
- Chemical Sciences and Engineering Division Argonne National Laboratory Lemont Illinois
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11
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Jasper AW. Microcanonical Rate Constants for Unimolecular Reactions in the Low-Pressure Limit. J Phys Chem A 2020; 124:1205-1226. [DOI: 10.1021/acs.jpca.9b10693] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ahren W. Jasper
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
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12
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Ahamed SS, Mahanta H, Paul AK. A Competition between Dissociation Pathway and Energy Transfer Pathway: Unimolecular Dissociation of a Benzene-Hexafluorobenzene Complex in Nitrogen Bath. J Phys Chem A 2019; 123:10663-10675. [PMID: 31755713 DOI: 10.1021/acs.jpca.9b07258] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The unimolecular dissociation of a benzene-hexafluorobenzene complex at 1000, 1500, and 2000 K is studied inside a bath of 1000 N2 molecules kept at 300 K using chemical dynamics simulation. Three bath densities of 20, 324, and 750 kg/m3 are considered. The dissociation dynamics of the complex at a 20 kg/m3 bath density is found to be similar to that in the gas phase, whereas the dynamics is drastically different at higher bath densities. The microcanonical/canonical dissociation rate constants for the three bath densities are calculated and fitted to the Arrhenius equation. The activation energies are found to be similar to the gas-phase one. However, the pre-exponential factor is lower and decreases with the increase in bath density. The vibrational degree of freedom of the complex more effectively participates in the collisional energy transfer to the N2 bath, whereas the translational and rotational degrees of freedom of N2 receive the transferred energy. The energy transfer efficiency increases with the increase in bath density. The time scale of the energy transfer pathway is more than that of the dissociation pathway, and negligible direct dissociation of the complex is observed from the simulation at the highest bath density.
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Affiliation(s)
- Sk Samir Ahamed
- Department of Chemistry , National Institute of Technology Meghalaya , Shillong 793003 , Meghalaya , India
| | - Himashree Mahanta
- Department of Chemistry , National Institute of Technology Meghalaya , Shillong 793003 , Meghalaya , India
| | - Amit K Paul
- Department of Chemistry , National Institute of Technology Meghalaya , Shillong 793003 , Meghalaya , India
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13
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Wiens JP, Alexander WA. Sodium atom beam collisions with the liquid glycerol surface: Mass effects of deuteration. Chem Phys Lett 2019. [DOI: 10.1016/j.cplett.2019.06.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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14
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Wilhelm MJ, Dai HL. Collisional Energy Transfer from Vibrationally Excited Hydrogen Isocyanide. J Phys Chem A 2019; 123:6927-6936. [PMID: 31339307 DOI: 10.1021/acs.jpca.9b07041] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Collisional deactivation of vibrationally excited hydrogen isocyanide (HNC) by inert gas atoms was characterized using nanosecond time-resolved Fourier transform infrared emission spectroscopy. HNC, with an average nascent internal energy of 25.9 ± 1.4 kcal mol-1, was generated following the 193 nm photolysis of vinyl cyanide (CH2CHCN) and collisionally deactivated with the series of inert atomic gases: He, Ar, Kr, and Xe. Time-dependent IR emission allows simultaneous experimental observation of the ν1 NH and ν3 NC stretch emissions from vibrationally excited HNC. Subsequent spectral fit analysis enables direct determination of the average energy of HNC in each spectrum and therefore a measure of the average energy lost per collision, ⟨ΔE⟩, as a function of internal energy. Collisional deactivation of excited HNC is shown to be relatively efficient, exhibiting ⟨ΔE⟩ values more than an order of magnitude larger than comparably sized molecules at similar internal energies. Furthermore, the lighter inert gases are shown to be more efficient quenchers. Both observations can be qualitatively explained by the momentum gap law modeled through the repulsive force dominated vibration-to-translation energy transfer mechanism. The feasibility of efficient collisional deactivation as a contributing factor to the observed overabundance of astrophysical HNC is discussed.
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Affiliation(s)
- Michael J Wilhelm
- Department of Chemistry , Temple University , 1901 N. 13th Street , Philadelphia 19122 , Pennsylvania , United States
| | - Hai-Lung Dai
- Department of Chemistry , Temple University , 1901 N. 13th Street , Philadelphia 19122 , Pennsylvania , United States
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15
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Wang H, Wen K, You X, Mao Q, Luo KH, Pilling MJ, Robertson SH. Energy transfer in intermolecular collisions of polycyclic aromatic hydrocarbons with bath gases He and Ar. J Chem Phys 2019; 151:044301. [PMID: 31370521 DOI: 10.1063/1.5094104] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Classical trajectory simulations of intermolecular collisions were performed for a series of polycyclic aromatic hydrocarbons interacting with the bath gases helium and argon for bath gas temperature from 300 to 2500 K. The phase-space average energy transferred per deactivating collision, ⟨∆Edown⟩, was obtained. The Buckingham pairwise intermolecular potentials were validated against high-level quantum chemistry calculations and used in the simulations. The reactive force-field was used to describe intramolecular potentials. The dependence of ⟨∆Edown⟩ on initial vibrational energy is discussed. A canonical sampling method was compared with a microcanonical sampling method for selecting initial vibrational energy at high bath gas temperatures. Uncertainties introduced by the initial angular momentum distribution were identified. The dependence of the collisional energy transfer parameters on the type of bath gas and the molecular structure of polycyclic aromatic hydrocarbons was examined.
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Affiliation(s)
- Hongmiao Wang
- Center for Combustion Energy, Tsinghua University, Beijing 100084, China
| | - Kaicheng Wen
- Center for Combustion Energy, Tsinghua University, Beijing 100084, China
| | - Xiaoqing You
- Center for Combustion Energy, Tsinghua University, Beijing 100084, China
| | - Qian Mao
- Center for Combustion Energy, Tsinghua University, Beijing 100084, China
| | - Kai Hong Luo
- Department of Mechanical Engineering, University College London, Torrington Place, London WC1E 7JE, United Kingdom
| | - Michael J Pilling
- School of Chemistry, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Struan H Robertson
- Dassault Systèmes, BIOVIA, 334, Cambridge Science Park, Cambridge CB4 0WN, United Kingdom
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16
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Mahanta H, Baishya D, Ahamed SS, Paul AK. Chemical Dynamics Simulations on Association and Ensuing Dissociation of a Benzene-Hexafluorobenzene Molecular System. J Phys Chem A 2019; 123:5019-5026. [PMID: 31145623 DOI: 10.1021/acs.jpca.9b02332] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Chemical dynamics simulations are performed to study the association of benzene (Bz) and hexafluorobenzene (HFB) followed by the ensuing dissociation of the Bz-HFB complex. The calculations are done for 1000, 1500, and 2000 K with an impact parameter ( b) range of 0-10 Å at each temperature. Almost no complexes are observed to form at b = 8 and 10 Å. Following three different methods of calculation of the temperature-dependent association rate constant kasso( T), the values obtained are 1.67 × 10-10, 1.86 × 10-10, and 2.05 × 10-10 cm3/molecule·s with a standard deviation of approximately 0.1 × 10-10 cm3/molecule·s for T = 1500 K. Among those values of kasso( T), the middle one is obtained by considering a relative translational energy of 3 RT/2 at T = 1500 K, and the same is followed to calculate kasso( T) at 1000 and 2000 K. The Arrhenius parameters, using the kasso( T) values at three temperatures, are 0.203 × 10-10 cm3/molecule·s for the pre-exponential factor and -5.79 kcal/mol for the activation energy. The absolute value of the latter is similar to the Bz + HFB association energy of 5.93 kcal/mol. The ensuing dissociation dynamics of the complex is significantly different from the unimolecular dissociation dynamics, and an exponential function fits the N( t - t0)/ N( t0) curves comparatively well. The ensuing dissociation is also observed to be independent of time for a statistically large sample size.
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Affiliation(s)
- Himashree Mahanta
- Department of Chemistry , National Institute of Technology Meghalaya , Shillong 793003 , Meghalaya , India
| | - Daradi Baishya
- Department of Chemistry , National Institute of Technology Meghalaya , Shillong 793003 , Meghalaya , India
| | - Sk Samir Ahamed
- Department of Chemistry , National Institute of Technology Meghalaya , Shillong 793003 , Meghalaya , India
| | - Amit K Paul
- Department of Chemistry , National Institute of Technology Meghalaya , Shillong 793003 , Meghalaya , India
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17
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Jasper AW, Davis MJ. Parameterization Strategies for Intermolecular Potentials for Predicting Trajectory-Based Collision Parameters. J Phys Chem A 2019; 123:3464-3480. [DOI: 10.1021/acs.jpca.9b01918] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ahren W. Jasper
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Michael J. Davis
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
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18
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Mahanta H, Baishya D, Ahamed SS, Paul AK. A Better Understanding of the Unimolecular Dissociation Dynamics of Weakly Bound Aromatic Compounds at High Temperature: A Study on C 6H 6-C 6F 6 and Comparison with C 6H 6 Dimer. J Phys Chem A 2019; 123:2517-2526. [PMID: 30848910 DOI: 10.1021/acs.jpca.8b12188] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Chemical dynamics simulations are performed to study the unimolecular dissociation of the benzene (Bz)-hexafluorobenzene (HFB) complex at five different temperatures ranging from 1000 to 2000 K, and the results are compared with that of the Bz dimer at common simulation temperatures. Bz-HFB, in comparison with Bz dimer, possesses a much attractive intermolecular interaction, a very different equilibrium geometry, and a lower average quantum vibrational excitation energy at a given temperature. Six low-frequency modes of Bz-HFB are formed by Bz + HFB association which are weakly coupled with the vibrational modes of Bz and HFB. However, this coupling is found much stronger in Bz-HFB compared to the same in the Bz dimer. The simulations are done with very good potential energy parameters taken from the literature. Considering the canonical (TST) model, the unimolecular dissociation rate constant at each temperature is calculated and fitted to the Arrhenius equation. An activation energy of 5.0 kcal/mol and a pre-exponential factor of 2.39 × 1012 s-1 are obtained, which are of expected magnitudes. The responsible vibrational mode for dissociation is identified by performing normal-mode analysis. Simulations with random excitations of high-frequency Bz and HFB modes and low-frequency inter-Bz-HFB vibrational modes of the Bz-HFB complex are also performed. The intramolecular vibrational energy redistribution (IVR) time and the unimolecular dissociation rate constants are calculated from these simulations. The latter shows good agreement with the same obtained from simulation with random excitation of all vibrational modes.
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Affiliation(s)
- Himashree Mahanta
- Department of Chemistry , National Institute of Technology Meghalaya , Shillong 793003 , Meghalaya , India
| | - Daradi Baishya
- Department of Chemistry , National Institute of Technology Meghalaya , Shillong 793003 , Meghalaya , India
| | - Sk Samir Ahamed
- Department of Chemistry , National Institute of Technology Meghalaya , Shillong 793003 , Meghalaya , India
| | - Amit K Paul
- Department of Chemistry , National Institute of Technology Meghalaya , Shillong 793003 , Meghalaya , India
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19
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Kim H, Bhandari HN, Pratihar S, Hase WL. Chemical Dynamics Simulation of Energy Transfer: Propylbenzene Cation and N2 Collisions. J Phys Chem A 2019; 123:2301-2309. [PMID: 30794410 DOI: 10.1021/acs.jpca.9b00111] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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20
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Classical trajectory studies of collisional energy transfer. ACTA ACUST UNITED AC 2019. [DOI: 10.1016/b978-0-444-64207-3.00003-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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21
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Experiments on collisional energy transfer. ACTA ACUST UNITED AC 2019. [DOI: 10.1016/b978-0-444-64207-3.00001-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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22
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da Silva RS, Ballester MY. A theoretical study of energy transfer in Ar( 1S) + SO 2( X ̃ 1 A ') collisions: Cross sections and rate coefficients for vibrational transitions. J Chem Phys 2018; 149:144309. [PMID: 30316261 DOI: 10.1063/1.5051349] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Vibrational transitions, induced by collisions between rare-gas atoms and molecules, play a key role in many problems of interest in physics and chemistry. A theoretical investigation of the translation-to-vibration (T-V) energy transfer process in argon atom and sulfur dioxide molecule collisions is presented here. For such a purpose, the framework of the quasi-classical trajectory (QCT) methodology was followed over the range of translational energies 2 ≤ Etr/kcal mol-1 ≤ 100. A new realistic potential energy surface (PES) for the ArSO2 system was developed using pairwise addition for the four-body energy term within the double many-body expansion. The topological features of the obtained function are compared with a previous one reported by Hippler et al. [J. Phys. Chem. 90, 6158 (1986)]. To test the accuracy of the PES, additional coupled cluster singles and doubles method with a perturbative contribution of connected triples calculations were carried out for the global minimum configuration. From dynamical calculations, the cross sections for the T-V excitation process indicate a barrier-type mechanism due to strong repulsive interactions between SO2 molecules and the Ar atom. Corrections to zero-point energy leakage in QCT were carried out using vibrational energy quantum mechanical threshold of the complex and variations. Rate coefficients and cross sections are calculated for some vibrational transitions using pseudo-quantization approaches of the vibrational energy of products. Main attributes of the title molecular collision are discussed and compared with available information in the literature.
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Affiliation(s)
- Ramon S da Silva
- Departamento de Física, Universidade Federal de Juiz de Fora, Juiz de Fora, MG 36036-330, Brazil
| | - Maikel Y Ballester
- Departamento de Física, Universidade Federal de Juiz de Fora, Juiz de Fora, MG 36036-330, Brazil
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23
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Abstract
Pressure dependence of unimolecular reaction rates is governed by the energy transfer in collisions of reactants with bath gas molecules. Pressure-dependent rate constants can be theoretically determined by solving master equations for unimolecular reactions. In general, master equation formulations describe energy transfer processes using a collision frequency and a probability distribution model of the energy transferred per collision. The present study proposes a novel method for determining the collision frequency from the results of classical trajectory calculations. Classical trajectories for collisions of several polyatomic molecules (ethane, methane, tetrafluoromethane, and cyclohexane) with monatomic colliders (Ar, Kr, and Xe) were calculated on potential energy surfaces described by the third-order density-functional tight-binding method in combination with simple pairwise interaction potentials. Low-order (including non-integer-order) moments of the energy transferred in deactivating collisions were extracted from the trajectories and compared with those derived using some probability distribution models. The comparison demonstrates the inadequacy of the conventional Lennard-Jones collision model for representing the collision frequency and suggests a robust method for evaluating the collision frequency that is consistent with a given probability distribution model, such as the exponential-down model. The resulting collision frequencies for the exponential-down model are substantially higher than the Lennard-Jones collision frequencies and are close to the (hypothetical) capture rate constants for dispersion interactions. The practical adequacy of the exponential-down model is also briefly discussed.
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Affiliation(s)
- Akira Matsugi
- National Institute of Advanced Industrial Science and Technology (AIST) , 16-1 Onogawa, Tsukuba, Ibaraki 305-8569, Japan
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24
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Liu Y, Huang Y, Ma J, Li J. Classical Trajectory Study of Collision Energy Transfer between Ne and C2H2 on a Full Dimensional Accurate Potential Energy Surface. J Phys Chem A 2018; 122:1521-1530. [DOI: 10.1021/acs.jpca.7b11483] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yang Liu
- School
of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044, China
| | - Yin Huang
- School
of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044, China
| | - Jianyi Ma
- Institute
of Atomic and Molecular Physics, Sichuan University, Chengdu, Sichuan 610065, China
| | - Jun Li
- School
of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044, China
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25
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Paul AK, Donzis D, Hase WL. Collisional Intermolecular Energy Transfer from a N 2 Bath at Room Temperature to a Vibrationlly "Cold" C 6F 6 Molecule Using Chemical Dynamics Simulations. J Phys Chem A 2017; 121:4049-4057. [PMID: 28485962 DOI: 10.1021/acs.jpca.7b00948] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Chemical dynamics simulations were performed to study collisional intermolecular energy transfer from a thermalized N2 bath at 300 K to vibrationally "cold" C6F6. The vibrational temperature of C6F6 is taken as 50 K, which corresponds to a classical vibrational energy of 2.98 kcal/mol. The temperature ratio between C6F6 and the bath is 1/6, the reciprocal of the same ratio for previous "hot" C6F6 simulations (J. Chem. Phys. 2014, 140, 194103). Simulations were also done for a C6F6 vibrational temperature of 0 K. The average energy of C6F6 versus time is well fit by a biexponential function which gives a slightly larger short time rate component, k1, but a four times smaller long time rate component, k2, compared to those obtained from the "hot" C6F6 simulations. The average energy transferred per collision depends on the difference between the average energy of C6F6 and the final C6F6 energy after equilibration with the bath, but not on the temperature ratio of C6F6 and the bath. The translational and rotational degrees of freedom of the N2 bath transfer their energies to the vibrational degrees of freedom of C6F6. The energies of the N2 vibrational mode and translational and rotational modes of C6F6 remain unchanged during the energy transfer. It is also found that the energy distribution of C6F6 broadens as energy is transferred from the bath, with an almost linear increase in the deviation of the C6F6 energies from the average C6F6 energy as the average energy of C6F6 increases.
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Affiliation(s)
- Amit K Paul
- Department of Chemistry and Biochemistry, Texas Tech University , Lubbock, Texas 79409, United States.,Department of Chemistry, National Institute of Technology , Meghalaya, Shillong, Meghalaya 793003, India
| | - Diego Donzis
- Department of Chemistry, Texas A&M University , College Station, Texas 77842, United States
| | - William L Hase
- Department of Chemistry and Biochemistry, Texas Tech University , Lubbock, Texas 79409, United States
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26
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Kim H, Paul AK, Pratihar S, Hase WL. Chemical Dynamics Simulations of Intermolecular Energy Transfer: Azulene + N2 Collisions. J Phys Chem A 2016; 120:5187-96. [PMID: 27182630 DOI: 10.1021/acs.jpca.6b00893] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Chemical dynamics simulations were performed to investigate collisional energy transfer from highly vibrationally excited azulene (Az*) in a N2 bath. The intermolecular potential between Az and N2, used for the simulations, was determined from MP2/6-31+G* ab initio calculations. Az* is prepared with an 87.5 kcal/mol excitation energy by using quantum microcanonical sampling, including its 95.7 kcal/mol zero-point energy. The average energy of Az* versus time, obtained from the simulations, shows different rates of Az* deactivation depending on the N2 bath density. Using the N2 bath density and Lennard-Jones collision number, the average energy transfer per collision ⟨ΔEc⟩ was obtained for Az* as it is collisionally relaxed. By comparing ⟨ΔEc⟩ versus the bath density, the single collision limiting density was found for energy transfer. The resulting ⟨ΔEc⟩, for an 87.5 kcal/mol excitation energy, is 0.30 ± 0.01 and 0.32 ± 0.01 kcal/mol for harmonic and anharmonic Az potentials, respectively. For comparison, the experimental value is 0.57 ± 0.11 kcal/mol. During Az* relaxation there is no appreciable energy transfer to Az translation and rotation, and the energy transfer is to the N2 bath.
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Affiliation(s)
- Hyunsik Kim
- Department of Chemistry and Biochemistry, Texas Tech University , Lubbock, Texas 79409, United States
| | - Amit K Paul
- Department of Chemistry and Biochemistry, Texas Tech University , Lubbock, Texas 79409, United States
| | - Subha Pratihar
- Department of Chemistry and Biochemistry, Texas Tech University , Lubbock, Texas 79409, United States
| | - William L Hase
- Department of Chemistry and Biochemistry, Texas Tech University , Lubbock, Texas 79409, United States
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27
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West NA, Winner JD, Bowersox RDW, North SW. Resolving the energy and temperature dependence of C6H6∗ collisional relaxation via time-dependent bath temperature measurements. J Chem Phys 2016; 145:014308. [DOI: 10.1063/1.4954896] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Affiliation(s)
- Niclas A. West
- Department of Chemistry, Texas A&M University, 3012 TAMU, College Station, Texas 77842, USA
| | - Joshua D. Winner
- Department of Chemistry, Texas A&M University, 3012 TAMU, College Station, Texas 77842, USA
| | - Rodney D. W. Bowersox
- Department of Aerospace Engineering, Texas A&M University, 3141 TAMU, College Station, Texas 77842, USA
| | - Simon W. North
- Department of Chemistry, Texas A&M University, 3012 TAMU, College Station, Texas 77842, USA
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28
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Li J, Guo H. Permutationally invariant fitting of intermolecular potential energy surfaces: A case study of the Ne-C2H2 system. J Chem Phys 2015; 143:214304. [DOI: 10.1063/1.4936660] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Jun Li
- School of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044, China
| | - Hua Guo
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, USA
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29
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Ree J, Seo H, Lee SK, Shin HK. Collision-induced Energy Transfer between Toluene and Halogen Molecules and CH Bond Dissociation. B KOREAN CHEM SOC 2015. [DOI: 10.1002/bkcs.10525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Jongbaik Ree
- Department of Chemistry Education; Chonnam National University; Gwangju 500-757 Republic of Korea
| | - Hanna Seo
- Department of Chemistry Education; Chonnam National University; Gwangju 500-757 Republic of Korea
| | - Sang Kwon Lee
- Department of Chemistry Education; Chonnam National University; Gwangju 500-757 Republic of Korea
| | - Hyung Kyu Shin
- Department of Chemistry; University of Nevada; Reno NV 89557 USA
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30
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Steill JD, Jasper AW, Chandler DW. Determination of the collisional energy transfer distribution responsible for the collision-induced dissociation of NO2 with Ar. Chem Phys Lett 2015. [DOI: 10.1016/j.cplett.2015.06.035] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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31
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Conte R, Houston PL, Bowman JM. Trajectory and Model Studies of Collisions of Highly Excited Methane with Water Using an ab Initio Potential. J Phys Chem A 2015; 119:12304-17. [DOI: 10.1021/acs.jpca.5b06595] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Riccardo Conte
- Department
of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
| | - Paul L. Houston
- School
of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
- Department
of Chemistry and Chemical Biology, Cornell University, Baker Laboratory, Ithaca, New York 14852, United States
| | - Joel M. Bowman
- Department
of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
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32
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Paul AK, Kolakkandy S, Hase WL. Dynamics of Na+(Benzene) + Benzene Association and Ensuing Na+(Benzene)2* Dissociation. J Phys Chem A 2015; 119:7894-904. [DOI: 10.1021/acs.jpca.5b01922] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Amit K. Paul
- Department
of Chemistry and
Biochemistry Texas Tech University, Lubbock, Texas 79409, United States
| | - Sujitha Kolakkandy
- Department
of Chemistry and
Biochemistry Texas Tech University, Lubbock, Texas 79409, United States
| | - William L. Hase
- Department
of Chemistry and
Biochemistry Texas Tech University, Lubbock, Texas 79409, United States
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33
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Houston PL, Conte R, Bowman JM. A Model For Energy Transfer in Collisions of Atoms with Highly Excited Molecules. J Phys Chem A 2015; 119:4695-710. [DOI: 10.1021/acs.jpca.5b00219] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Paul L. Houston
- School
of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Riccardo Conte
- Department
of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
| | - Joel M. Bowman
- Department
of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
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34
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Vereecken L, Glowacki DR, Pilling MJ. Theoretical Chemical Kinetics in Tropospheric Chemistry: Methodologies and Applications. Chem Rev 2015; 115:4063-114. [DOI: 10.1021/cr500488p] [Citation(s) in RCA: 146] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Luc Vereecken
- Max Planck Institute for Chemistry, 55128 Mainz, Germany
| | - David R. Glowacki
- PULSE
Institute and Department of Chemistry, Stanford University, Stanford, California 94305, United States
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
- School
of Chemistry, University of Bristol, Bristol BS8 1TS, United Kingdom
- Department
of Computer Science, University of Bristol, Bristol BS8 1UB, United Kingdom
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35
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Kolakkandy S, Paul AK, Pratihar S, Kohale SC, Barnes GL, Wang H, Hase WL. Energy and temperature dependent dissociation of the Na+(benzene)1,2 clusters: Importance of anharmonicity. J Chem Phys 2015; 142:044306. [DOI: 10.1063/1.4906232] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Sujitha Kolakkandy
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409, USA
| | - Amit K. Paul
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409, USA
| | - Subha Pratihar
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409, USA
| | - Swapnil C. Kohale
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409, USA
| | - George L. Barnes
- Department of Chemistry and Biochemistry, Siena College, Loudonville, New York 12211-1462, USA
| | - Hai Wang
- Department of Mechanical Engineering, Stanford University, Stanford, California 94305, USA
| | - William L. Hase
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409, USA
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36
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Rivera-Rivera LA, Wagner AF, Sewell TD, Thompson DL. Pressure effects on the relaxation of an excited nitromethane molecule in an argon bath. J Chem Phys 2015; 142:014303. [PMID: 25573557 DOI: 10.1063/1.4904314] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Classical molecular dynamics simulations were performed to study the relaxation of nitromethane in an Ar bath (of 1000 atoms) at 300 K and pressures 10, 50, 75, 100, 125, 150, 300, and 400 atm. The molecule was instantaneously excited by statistically distributing 50 kcal/mol among the internal degrees of freedom. At each pressure, 1000 trajectories were integrated for 1000 ps, except for 10 atm, for which the integration time was 5000 ps. The computed ensemble-averaged rotational energy decay is ∼100 times faster than the vibrational energy decay. Both rotational and vibrational decay curves can be satisfactorily fit with the Lendvay-Schatz function, which involves two parameters: one for the initial rate and one for the curvature of the decay curve. The decay curves for all pressures exhibit positive curvature implying the rate slows as the molecule loses energy. The initial rotational relaxation rate is directly proportional to density over the interval of simulated densities, but the initial vibrational relaxation rate decreases with increasing density relative to the extrapolation of the limiting low-pressure proportionality to density. The initial vibrational relaxation rate and curvature are fit as functions of density. For the initial vibrational relaxation rate, the functional form of the fit arises from a combinatorial model for the frequency of nitromethane "simultaneously" colliding with multiple Ar atoms. Roll-off of the initial rate from its low-density extrapolation occurs because the cross section for collision events with L Ar atoms increases with L more slowly than L times the cross section for collision events with one Ar atom. The resulting density-dependent functions of the initial rate and curvature represent, reasonably well, all the vibrational decay curves except at the lowest density for which the functions overestimate the rate of decay. The decay over all gas phase densities is predicted by extrapolating the fits to condensed-phase densities.
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Affiliation(s)
- Luis A Rivera-Rivera
- Department of Chemistry, University of Missouri-Columbia, Columbia, Missouri 65211-7600, USA
| | - Albert F Wagner
- Argonne National Laboratory, Chemical Sciences and Engineering Division, Argonne, Illinois 60439, USA
| | - Thomas D Sewell
- Department of Chemistry, University of Missouri-Columbia, Columbia, Missouri 65211-7600, USA
| | - Donald L Thompson
- Department of Chemistry, University of Missouri-Columbia, Columbia, Missouri 65211-7600, USA
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37
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Kim K, Johnson AM, Powell AL, Mitchell DG, Sevy ET. High resolution IR diode laser study of collisional energy transfer between highly vibrationally excited monofluorobenzene and CO2: the effect of donor fluorination on strong collision energy transfer. J Chem Phys 2014; 141:234306. [PMID: 25527934 DOI: 10.1063/1.4903252] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Collisional energy transfer between vibrational ground state CO2 and highly vibrationally excited monofluorobenzene (MFB) was studied using narrow bandwidth (0.0003 cm(-1)) IR diode laser absorption spectroscopy. Highly vibrationally excited MFB with E' = ∼41,000 cm(-1) was prepared by 248 nm UV excitation followed by rapid radiationless internal conversion to the electronic ground state (S1→S0*). The amount of vibrational energy transferred from hot MFB into rotations and translations of CO2 via collisions was measured by probing the scattered CO2 using the IR diode laser. The absolute state specific energy transfer rate constants and scattering probabilities for single collisions between hot MFB and CO2 were measured and used to determine the energy transfer probability distribution function, P(E,E'), in the large ΔE region. P(E,E') was then fit to a bi-exponential function and extrapolated to the low ΔE region. P(E,E') and the biexponential fit data were used to determine the partitioning between weak and strong collisions as well as investigate molecular properties responsible for large collisional energy transfer events. Fermi's Golden rule was used to model the shape of P(E,E') and identify which donor vibrational motions are primarily responsible for energy transfer. In general, the results suggest that low-frequency MFB vibrational modes are primarily responsible for strong collisions, and govern the shape and magnitude of P(E,E'). Where deviations from this general trend occur, vibrational modes with large negative anharmonicity constants are more efficient energy gateways than modes with similar frequency, while vibrational modes with large positive anharmonicity constants are less efficient at energy transfer than modes of similar frequency.
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Affiliation(s)
- Kilyoung Kim
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, USA
| | - Alan M Johnson
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, USA
| | - Amber L Powell
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, USA
| | - Deborah G Mitchell
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, USA
| | - Eric T Sevy
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, USA
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38
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Jasper AW, Pelzer KM, Miller JA, Kamarchik E, Harding LB, Klippenstein SJ. Predictive a priori pressure-dependent kinetics. Science 2014; 346:1212-5. [DOI: 10.1126/science.1260856] [Citation(s) in RCA: 127] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The ability to predict the pressure dependence of chemical reaction rates would be a great boon to kinetic modeling of processes such as combustion and atmospheric chemistry. This pressure dependence is intimately related to the rate of collision-induced transitions in energy E and angular momentum J. We present a scheme for predicting this pressure dependence based on coupling trajectory-based determinations of moments of the E,J-resolved collisional transfer rates with the two-dimensional master equation. This completely a priori procedure provides a means for proceeding beyond the empiricism of prior work. The requisite microcanonical dissociation rates are obtained from ab initio transition state theory. Predictions for the CH4 = CH3 + H and C2H3 = C2H2 + H reaction systems are in excellent agreement with experiment.
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39
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Houston PL, Conte R, Bowman JM. Collisional Energy Transfer in Highly Excited Molecules. J Phys Chem A 2014; 118:7758-75. [DOI: 10.1021/jp506202g] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Paul L. Houston
- School of Chemistry
and Biochemistry, Georgia Institute of Technology, 901 Atlantic Drive, Atlanta, Georgia 30332, United States
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14852, United States
| | - Riccardo Conte
- Department
of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
| | - Joel M. Bowman
- Department
of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
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40
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Conte R, Houston PL, Bowman JM. Trajectory Study of Energy Transfer and Unimolecular Dissociation of Highly Excited Allyl with Argon. J Phys Chem A 2014; 118:7742-57. [DOI: 10.1021/jp5062013] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Riccardo Conte
- Department
of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
| | - Paul L. Houston
- School
of Chemistry and Biochemistry Georgia Institute of Technology, Atlanta, Georgia 30332, United States
- Department
of Chemistry and Chemical Biology, Cornell University, Baker Laboratory, Ithaca, New York 14852, United States
| | - Joel M. Bowman
- Department
of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
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41
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Paul AK, Kohale SC, Pratihar S, Sun R, North SW, Hase WL. A unified model for simulating liquid and gas phase, intermolecular energy transfer: N2+ C6F6collisions. J Chem Phys 2014; 140:194103. [DOI: 10.1063/1.4875516] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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42
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Conte R, Houston PL, Bowman JM. Communication: A benchmark-quality, full-dimensional ab initio potential energy surface for Ar-HOCO. J Chem Phys 2014. [DOI: 10.1063/1.4871371] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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43
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Ree J, Kim YH, Shin HK. Collision-induced Energy Transfer and Bond Dissociation in Toluene by H2/D2. B KOREAN CHEM SOC 2013. [DOI: 10.5012/bkcs.2013.34.12.3641] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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44
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Conte R, Houston PL, Bowman JM. Classical Trajectory Study of Energy Transfer in Collisions of Highly Excited Allyl Radical with Argon. J Phys Chem A 2013; 117:14028-41. [DOI: 10.1021/jp410315r] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Riccardo Conte
- Department of Chemistry and Cherry L. Emerson
Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
| | - Paul L. Houston
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Joel M. Bowman
- Department of Chemistry and Cherry L. Emerson
Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
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45
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Jasper AW, Miller JA, Klippenstein SJ. Collision Efficiency of Water in the Unimolecular Reaction CH4 (+H2O) ⇆ CH3 + H (+H2O): One-Dimensional and Two-Dimensional Solutions of the Low-Pressure-Limit Master Equation. J Phys Chem A 2013; 117:12243-55. [DOI: 10.1021/jp409086w] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ahren W. Jasper
- Combustion
Research Facility, Sandia National Laboratories, P.O. Box 969, Livermore, California 94551-0969, United States
| | - James A. Miller
- Chemical
Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439, United States
| | - Stephen J. Klippenstein
- Chemical
Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439, United States
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46
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Du J, Sassin NA, Havey DK, Hsu K, Mullin AS. Full State-Resolved Energy Gain Profiles of CO2 from Collisions with Highly Vibrationally Excited Molecules. II. Energy-Dependent Pyrazine (E = 32 700 and 37 900 cm–1) Relaxation. J Phys Chem A 2013; 117:12104-15. [DOI: 10.1021/jp404939s] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Juan Du
- Department of Chemistry & Biochemistry, University of Maryland, College Park, Maryland 20742, United States
| | - Nicholas A. Sassin
- Department of Chemistry & Biochemistry, University of Maryland, College Park, Maryland 20742, United States
| | - Daniel K. Havey
- Department of Chemistry & Biochemistry, University of Maryland, College Park, Maryland 20742, United States
| | - Kailin Hsu
- Department of Chemistry & Biochemistry, University of Maryland, College Park, Maryland 20742, United States
| | - Amy S. Mullin
- Department of Chemistry & Biochemistry, University of Maryland, College Park, Maryland 20742, United States
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47
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Alexander WA, Zhang J, Murray VJ, Nathanson GM, Minton TK. Kinematics and dynamics of atomic-beam scattering on liquid and self-assembled monolayer surfaces. Faraday Discuss 2013; 157:355-74; discussion 375-98. [PMID: 23230778 DOI: 10.1039/c2fd20034a] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We have conducted investigations of the energy transfer dynamics of atomic oxygen and argon scattering from hydrocarbon and fluorocarbon surfaces. In light of these results, we appraise the applicability and value of a kinematic scattering model, which views a gas-surface interaction as a gas-phase-like collision between an incident atom or molecule and a localized region of the surface with an effective mass. We have applied this model to interpret the effective surface mass and energy transfer when atoms strike two different surfaces under identical bombardment conditions. To this end, we have collected new data, and we have re-examined existing data sets from both molecular-beam experiments and molecular dynamics simulations. We seek to identify trends that could lead to a robust general understanding of energy transfer processes induced by collisions of gas-phase species with liquid and semi-solid surfaces.
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Affiliation(s)
- William A Alexander
- Department of Chemistry and Biochemistry, Montana State University, 103 Chem/Biochem Bldg., Bozeman, MT 59717, USA
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48
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Jasper AW, Miller JA. Theoretical Unimolecular Kinetics for CH4 + M ⇄ CH3 + H + M in Eight Baths, M = He, Ne, Ar, Kr, H2, N2, CO, and CH4. J Phys Chem A 2011; 115:6438-55. [DOI: 10.1021/jp200048n] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- Ahren W. Jasper
- Combustion Research Facility, Sandia National Laboratories, P.O. Box 969, Livermore, California 94551-0969, United States
| | - James A. Miller
- Combustion Research Facility, Sandia National Laboratories, P.O. Box 969, Livermore, California 94551-0969, United States
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49
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Barker JR, Weston RE. Collisional Energy Transfer Probability Densities P(E, J; E′, J′) for Monatomics Colliding with Large Molecules. J Phys Chem A 2010; 114:10619-33. [DOI: 10.1021/jp106443d] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- John R. Barker
- Atmospheric, Oceanic, and Space Sciences, University of Michigan, Ann Arbor, Michigan 48109-2143, and Department of Chemistry, Brookhaven National Laboratory, Upton, New York 11973
| | - Ralph E. Weston
- Atmospheric, Oceanic, and Space Sciences, University of Michigan, Ann Arbor, Michigan 48109-2143, and Department of Chemistry, Brookhaven National Laboratory, Upton, New York 11973
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50
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Analytical solution of the master equation with the transition probability derived from dynamical considerations. Chem Phys 2010. [DOI: 10.1016/j.chemphys.2010.05.032] [Citation(s) in RCA: 4] [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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