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Mao L, Liu J, Habibulla N, Qiu Y. Experimental study of rotational relaxation for D2(1,12) in collisions with N2. J Chem Phys 2024; 160:154305. [PMID: 38624121 DOI: 10.1063/5.0197067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Accepted: 03/28/2024] [Indexed: 04/17/2024] Open
Abstract
The rotational relaxation behavior of D2(1,12) in a D2-N2 mixture was investigated using coherent anti-Stokes Raman scattering (CARS) technique. The rovibrational level v = 1 and J = 12 of D2 was selectively excited through stimulated Raman pumping while monitoring the temporal evolution of population for D2(1, J ≤ 12) molecules using time-resolved CARS spectroscopy. The results demonstrate that the rotational relaxation processes of D2(1,12) encompass both multi-quantum relaxation and continuous single-quantum relaxation. When α, the molar ratio of N2, is less than 0.5, D2(1,12) predominantly undergoes a single quantum relaxation process transition. However, when α ≥ 0.5, the multi-quantum relaxation mechanism gradually predominates. The total rotational relaxation rate coefficients of D2(1,12) collisions with N2 and D2 at 295 K were determined to be 3.974 × 10-14 and 1.179 × 10-14 cm3 s-1, respectively. The temperature dependence of rotational relaxation rate of D2(1,12) was investigated within the temperature range of 295-453 K. With increasing temperature, the dominant relaxation process exhibited an accelerated behavior, while the minor relaxation process remained largely unaffected. The rotational temperature of the D2 molecule at various N2 molar ratios was determined through the utilization of Boltzmann plots. The rotational temperature undergoes a rapid decline within 2 μs, corresponding to the near-resonant rotation-vibration relaxation process of D2(1,12) collisions with N2. The system reaches a quasi-equilibrium state when the delay time is 3 μs. The findings of this study can serve as a valuable empirical basis for further validation of the kinetic theory and simulation.
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Affiliation(s)
- Lin Mao
- Xinjiang Key Laboratory of Solid State Physics and Devices, Xinjiang University, Urumqi 830017, China
- School of Physical Science and Technology, Xinjiang University, Urumqi 830017, China
| | - Jing Liu
- Xinjiang Key Laboratory of Solid State Physics and Devices, Xinjiang University, Urumqi 830017, China
- School of Physical Science and Technology, Xinjiang University, Urumqi 830017, China
| | - Nurali Habibulla
- Xinjiang Key Laboratory of Solid State Physics and Devices, Xinjiang University, Urumqi 830017, China
- School of Physical Science and Technology, Xinjiang University, Urumqi 830017, China
| | - Yongbao Qiu
- Xinjiang Key Laboratory of Solid State Physics and Devices, Xinjiang University, Urumqi 830017, China
- School of Physical Science and Technology, Xinjiang University, Urumqi 830017, China
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2
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Hong Q, Sun Q, Pirani F, Valentín-Rodríguez MA, Hernández-Lamoneda R, Coletti C, Hernández MI, Bartolomei M. Energy exchange rate coefficients from vibrational inelastic O 2(Σg-3) + O 2(Σg-3) collisions on a new spin-averaged potential energy surface. J Chem Phys 2021; 154:064304. [PMID: 33588556 DOI: 10.1063/5.0041244] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A new spin-averaged potential energy surface (PES) for non-reactive O2(Σg-3) + O2(Σg-3) collisions is presented. The potential is formulated analytically according to the nature of the principal interaction components, with the main van der Waals contribution described through the improved Lennard-Jones model. All the parameters involved in the formulation, having a physical meaning, have been modulated in restricted variation ranges, exploiting a combined analysis of experimental and ab initio reference data. The new PES is shown to be able to reproduce a wealth of different physical properties, ranging from the second virial coefficients to transport properties (shear viscosity and thermal conductivity) and rate coefficients for inelastic scattering collisions. Rate coefficients for the vibrational inelastic processes of O2, including both vibration-to-vibration (V-V) and vibration-to-translation/rotation (V-T/R) energy exchanges, were then calculated on this PES using a mixed quantum-classical method. The effective formulation of the potential and its combination with an efficient, yet accurate, nuclear dynamics treatment allowed for the determination of a large database of V-V and V-T/R energy transfer rate coefficients in a wide temperature range.
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Affiliation(s)
- Qizhen Hong
- State Key Laboratory of High Temperature Gas Dynamics, Institute of Mechanics, Chinese Academy of Sciences, 100190 Beijing, China
| | - Quanhua Sun
- State Key Laboratory of High Temperature Gas Dynamics, Institute of Mechanics, Chinese Academy of Sciences, 100190 Beijing, China
| | - Fernando Pirani
- Dipartimento di Chimica, Biologia e Biotecnologie, Università di Perugia, via Elce di Sotto, 8 - 06183 Perugia, Italy
| | - Mónica A Valentín-Rodríguez
- Centro de Investigaciones Químicas-IICBA, Universidad Autónoma del Estado de Morelos, Cuernavaca 62210, Morelos, Mexico
| | - Ramón Hernández-Lamoneda
- Centro de Investigaciones Químicas-IICBA, Universidad Autónoma del Estado de Morelos, Cuernavaca 62210, Morelos, Mexico
| | - Cecilia Coletti
- Dipartimento di Farmacia, Università G. d'Annunzio Chieti-Pescara, via dei Vestini, 66100 Chieti, Italy
| | - Marta I Hernández
- Instituto de Física Fundamental - CSIC, C/Serrano 123, Madrid, Spain
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3
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Garrido JDD, Ellakkis S, Ballester MY. Relaxation of Vibrationally Excited OH Radical by SO. J Phys Chem A 2019; 123:8994-9007. [PMID: 31573197 DOI: 10.1021/acs.jpca.9b06062] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Juan de Dios Garrido
- Centro Interdisciplinar de Ciências da Natureza, Universidade Federal da Integração Latino-Americana, Foz do Iguaçu, PR 85866-000, Brazil
- Departamento de Física, Universidade Federal de Juiz de Fora, Juiz de Fora, MG 36036-330, Brazil
| | - Samah Ellakkis
- Centro Interdisciplinar de Ciências da Natureza, Universidade Federal da Integração Latino-Americana, Foz do Iguaçu, PR 85866-000, Brazil
| | - Maikel Y. Ballester
- Departamento de Física, Universidade Federal de Juiz de Fora, Juiz de Fora, MG 36036-330, Brazil
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4
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Tendo S, Tanimoto H, Uchiyama T, Goto H, Hara A, Fujihara K, Kohguchi H, Yamasaki K. Vibrational relaxation of S2(a1Δg) by collisions with SF6 and CF4. Chem Phys Lett 2017. [DOI: 10.1016/j.cplett.2017.06.030] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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5
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McCaffery AJ. Quantum state-resolved, bulk gas energetics: Comparison of theory and experiment. J Chem Phys 2016; 144:194304. [PMID: 27208946 DOI: 10.1063/1.4949268] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Until very recently, the computational model of state-to-state energy transfer in large gas mixtures, introduced by the author and co-workers, has had little experimental data with which to assess the accuracy of its predictions. In a novel experiment, Alghazi et al. [Chem. Phys. 448, 76 (2015)] followed the equilibration of highly vibrationally excited CsH(D) in baths of H2(D2) with simultaneous time- and quantum state-resolution. Modal temperatures of vibration, rotation, and translation for CsH(D) were obtained and presented as a function of pump-probe delay time. Here the data from this study are used as a test of the accuracy of the computational method, and in addition, the consequent changes in bath gas modal temperatures, not obtainable in the experiment, are predicted. Despite large discrepancies between initial CsH(D) vibrational states in the experiment and those available using the computational model, the quality of agreement is sufficient to conclude that the model's predictions constitute at least a very good representation of the overall equilibration that, for some measurements, is very accurate.
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Affiliation(s)
- Anthony J McCaffery
- Department of Chemistry, University of Sussex, Brighton, Sussex BN1 6SJ, United Kingdom
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6
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Mu B, Cui X, Shen Y, Dai K. State-resolved collisional relaxation of highly vibrationally excited CsH by CO2. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2015; 148:299-310. [PMID: 25909904 DOI: 10.1016/j.saa.2015.03.046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Revised: 08/18/2014] [Accepted: 03/02/2015] [Indexed: 06/04/2023]
Abstract
Quenching of highly vibrationally excited CsH(X(1)Σ(+), v=15-23) by collisions with CO2 was investigated. A significant fraction of the initial population of highly vibrationally excited CsH(v=22) was relaxed to a low vibrational level (Δv=-5). The near-resonant 5-1 vibration-to-vibration (V-V) energy was efficiently exchanged. The rate constants for the rotational levels of CO2(00(0)0) [J=36-60] and CO2(00(0)1) [J=5-31] from the collisions with excited CsH were determined. The experiments revealed that the collisions resulting in CO2(00(0)0) were accompanied by substantial excitation in rotation and translation. The vibrationally excited CO2(00(0)1) state exhibited rotational and translational energy distributions near those of the initial state. The total quenching rates relative to the probed state of excited CsH were determined for both CO2 states. The corresponding data indicated that the gains in the rotational and translational energies in CO2 were sensitive to the collisional depletion of excited CsH.
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Affiliation(s)
- Baoxia Mu
- School of Science, Xi'an Jiaotong University, Xi'an 710049, China; Department of Physics, Xinjiang University, Urumqi 830046, China.
| | - Xiuhua Cui
- Department of Physics, Xinjiang University, Urumqi 830046, China
| | - Yifan Shen
- Department of Physics, Xinjiang University, Urumqi 830046, China.
| | - Kang Dai
- Department of Physics, Xinjiang University, Urumqi 830046, China
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7
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Alghazi A, Liu J, Dai K, Shen YF. Quantum state-resolved energy redistribution of highly vibrationally excited CsH(D) by collisions withH2(D2). Chem Phys 2015. [DOI: 10.1016/j.chemphys.2014.12.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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8
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9
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Wang SY, Zhang B, Zhu DH, Dai K, Shen YF. Energy-dependence of vibrational relaxation between highly vibrationally excited KH (X1Σ+, ν"=14-23) and H2, and N2. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2012; 96:517-525. [PMID: 22728970 DOI: 10.1016/j.saa.2012.05.052] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2011] [Revised: 05/05/2012] [Accepted: 05/21/2012] [Indexed: 06/01/2023]
Abstract
Vibrational state total relaxation rate coefficients, k(ν") (M), for KH (ν"=14-23) by M=H(2) and N(2) have been investigated in an overtone pump-probe configuration. At ν"=14, 15, 16 and 17, the rate coefficients k(ν)(″) (M) increase linearly with vibrational quantum number. The region (ν"=18, 19, 20 and 21) where the dependence is much stronger than linear has significant contribution from multiquantum (Δν≥2) relaxation. For ν"=18, 19, 20 and 21, 0.25, 0.31, 0.38 and 0.31 of the initially prepared population undergo two-quantum (Δν=2) vibrational relaxation in KH (ν")+H(2) collisions. In KH (ν")+N(2), the time profile of ν"=14(15) after preparation of ν"=19(20) was measured. A clear bimodal distribution is observed. The time scale of the first peak is much shorter than the known collisional lifetimes of the intervening vibrational levels and thus a sequential single-quantum relaxation mechanism can be explicitly ruled out. Relaxation of KD with D(2) has been also investigated. The relaxation rate coefficients exhibit distinct maxima for both isotopes (KH and KD). We discuss possible explanation of the experimental results including mass effect, V-R energy transfer and V-V energy transfer.
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Affiliation(s)
- Shu-ying Wang
- School of Science, Xi'an Jiaotong University, Xi'an 710049, China.
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10
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McCaffery AJ, Pritchard M, Turner JF, Marsh RJ. Equilibration of OH (v7; v9) in air-like gas ensembles. Chem Phys Lett 2011. [DOI: 10.1016/j.cplett.2011.09.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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11
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Nguyen TNV, Timerghazin QK, Vach H, Peslherbe GH. Mechanically induced generation of highly reactive excited-state oxygen molecules in cluster scattering. J Chem Phys 2011; 134:064305. [PMID: 21322678 DOI: 10.1063/1.3509772] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Molecular electronic excitation in (O(2))(n) clusters induced by mechanical collisions via the "chemistry with a hammer" is investigated by a combination of molecular dynamics simulations and quantum chemistry calculations. Complete active space self-consistent field augmented with triple-zeta polarizable basis set quantum chemistry calculations of a compressed (O(2))(2) cluster model in various configurations reveal the emergence of possible pathways for the generation of electronically excited singlet O(2) molecules upon cluster compression and vibrational excitation, due to electronic curve-crossing and spin-orbit coupling. Extrapolation of the model (O(2))(2) results to larger clusters suggests a dramatic increase in the population of electronically excited O(2) products, and may account for the recently observed cluster-catalyzed oxidation of silicon surfaces, via singlet oxygen generation induced by cluster impact, followed by surface reaction of highly reactive singlet O(2) molecules. Extensive molecular dynamics simulations of (O(2))(n) clusters colliding onto a hot surface indeed reveal that cluster compression is sufficient under typical experimental conditions for nonadiabatic transitions to occur. This work highlights the importance of nonadiabatic effects in the "chemistry with a hammer."
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Affiliation(s)
- Tao-Nhân V Nguyen
- Centre for Research in Molecular Modeling and Department of Chemistry & Biochemistry, Concordia University, Montréal, Québec, H4B 1R6, Canada
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12
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McCaffery AJ, Marsh RJ. Modeling disequilibrium in gas ensembles: How quantum state populations evolve under multicollision conditions; CO∗+Ar, CO, O2, and N2. J Chem Phys 2010; 132:074304. [DOI: 10.1063/1.3319756] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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13
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Watanabe S, Fujii H, Kohguchi H, Hatano T, Tokue I, Yamasaki K. Kinetic study of vibrational energy transfer from a wide range of vibrational levels of O2(X(3)Sigma(g)-, v = 6-12) to CF4. J Phys Chem A 2008; 112:9290-5. [PMID: 18593107 DOI: 10.1021/jp802201m] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A wide range of vibrational levels of O2(X(3)Sigma(g)(-), v = 6-13) generated in the ultraviolet photolysis of O3 was selectively detected by the laser-induced fluorescence (LIF) technique. The time-resolved LIF-excited B(3)Sigma(u)(-)-X(3)Sigma(g)(-) system in the presence of CF4 has been recorded and analyzed by the integrated profiles method (IPM). The IPM permitted us to determine the rate coefficients k(v)(CF4) for vibrational relaxation of O2(X(3)Sigma(g)(-), v = 6-12) by collisions with CF4. Energy transfer from O2 (v = 6-12) to CF4 is surprisingly efficient compared to that of other polyatomic relaxation partners studied so far. The k(v)(CF4) increases with vibrational quantum number v from [1.5 +/- 0.2(2sigma)] x 10(-12) for v = 6 to [7.3 +/- 1.5(2sigma)] x 10(-11) for v = 12, indicating that the infrared-active nu3 vibrational mode of CF4 mainly governs the energy transfer with O2(X(3)Sigma(g)(-), v = 6-12). The correlation between the rate coefficients and fundamental infrared intensities has been discussed based on a comparison of the efficiency of energy transfer by several collision partners.
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Affiliation(s)
- Shinji Watanabe
- Department of Chemistry, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
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14
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Dayou F, Hernández MI, Campos-Martínez J, Hernández-Lamoneda R. Spin-orbit coupling in O2(v)+O2 collisions. II. Quantum scattering calculations on dimer states involving the XΣg−3, aΔg1, and bΣg+1 states of O2. J Chem Phys 2007; 126:194309. [PMID: 17523806 DOI: 10.1063/1.2734966] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The dynamics of collisional deactivation of O(2)(X (3)Sigma(g) (-),v=20-32) by O(2)(X (3)Sigma(g) (-),v(')=0) is investigated in detail by means of quantum-mechanical calculations. The theoretical approach involves ab initio potential energy surfaces correlating to the X (3)Sigma(g) (-), a (1)Delta(g), and b (1)Sigma(g) (+) states of O(2) and their corresponding spin-orbit couplings [F. Dayou, M. I. Hernandez, J. Campos-Martinez, and R. Hernandez-Lamoneda, J. Chem. Phys. 123, 074311 (2005)]. Accurate Rydberg-Klein-Rees potentials are included in order to improve the description of the vibrational structure of the fragments. The calculated Boltzmann-averaged depletion probabilities display a dependence with v in good agreement with experimental measurements. The onset of the vibrational-to-electronic (V-E) depletion mechanism is noticeable for v>/=26, and it is due to energy transfer to both a (1)Delta(g) and b (1)Sigma(g) (+) states of the diatom. For O(2)(X (3)Sigma(g) (-),v=28), a further and sharp increase in the removal probabilities is caused by a near degeneracy with the O(2)(b (1)Sigma(g) (+),v=19) vibrational state. Analysis of the temperature dependence of the Boltzmann-averaged probabilities indicates a transition from the vibrational-to-translational to the V-E energy transfer regime, which can be traced back to the behavior of the inelastic probabilities as functions of kinetic energy. Furthermore, branching ratios for outcomes through the three different electronic states show a strong propensity towards populating a unique vibrational level within each electronic state. These results provide supported evidence that spin-orbit couplings account for a large portion of the "dark channel" reported in total depletion measurements. New insight for further experimental and theoretical investigations is also given.
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Affiliation(s)
- Fabrice Dayou
- Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique, UMR 8112 du CNRS, Observatoire de Paris-Meudon, 5 place Jules Janssen, 92195 Meudon Cedex, France.
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15
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Watanabe S, Usuda SY, Fujii H, Hatano H, Tokue I, Yamasaki K. Vibrational relaxation of O2(X 3 Σ–g, v = 9–13) by collisions with O2. Phys Chem Chem Phys 2007; 9:4407-13. [PMID: 17687487 DOI: 10.1039/b702840g] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Vibrationally excited O(2)(X(3) Sigmag(-)) was generated in the UV laser flash photolysis of O(3) and single vibrational level was detected via laser-induced fluorescence (LIF) in the B(3) Sigmau(-)-X(3) Sigmag(-) system. The time-resolved LIF of adjacent vibrational levels has been analyzed by the integrated-profiles method and the rate coefficients for single-quantum relaxation, O(2)(X(3)Sigmag(-), v = 9-13)+ O(2)(v = 0)--> O(2)(X(3)Sigmag(-), v - 1)+ O(2)(v = 1), have been determined. To the best of our knowledge, the rate coefficients for v = 12 and 13 are measured for the first time in the present study. The efficiency of relaxation is higher at lower vibrational levels, indicating that a small energy mismatch is suitable for the energy transfer. The vibrational level dependence of all the rate coefficients for the relaxation measured in the present study and previously reported by several groups can be rationalized by the energy gap law.
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Affiliation(s)
- Shinji Watanabe
- Department of Chemistry, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima, 739-8526, Japan
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16
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Vach H, Nguyen TNV, Timerghazin QK, Peslherbe GH. Nonadiabatic ladder climbing during molecular collisions. PHYSICAL REVIEW LETTERS 2006; 97:143402. [PMID: 17155248 DOI: 10.1103/physrevlett.97.143402] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2005] [Revised: 06/30/2006] [Indexed: 05/12/2023]
Abstract
Combining classical molecular dynamics simulations with high level, multiconfigurational ab initio calculations, we demonstrate that even relatively mild collisions between ground state oxygen molecules can readily lead to the formation of highly reactive singlet oxygen molecules via a novel "ladder climbing" mechanism. We employ our findings to shed some light on two recent experiments that have remained poorly understood until now. The first one concerns the highly efficient cluster-catalyzed etching of silicon surfaces, whereas the second one involves a yet to be explained "dark channel" observed for the ozone photolysis in the stratosphere.
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Affiliation(s)
- Holger Vach
- LPICM, Ecole Polytechnique, CNRS, 91128, Palaiseau, France.
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17
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Yamasaki K, Fujii H, Watanabe S, Hatano T, Tokue I. Efficient vibrational relaxation of O2(X 3sigma(g)-, nu = 8) by collisions with CF4. Phys Chem Chem Phys 2006; 8:1936-41. [PMID: 16633681 DOI: 10.1039/b516695k] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A laser flash photolysis-laser-induced fluorescence (LIF) technique has been employed to study the relaxation kinetics of vibrationally excited O2(X 3sigma(g)-. The time-resolved LIF excited B 3sigma(u)(-)-X 3sigma(g)- system has been recorded and analyzed by the integrated-profiles method. The rate coefficient for vibrational relaxation of O2(X 3sigma(g)-, nu = 8) by collisions with CF(4), [1.4 +/- 0.3(2sigma)] x 10(-11) cm3 molecule(-1) s(-1), indicates that CF4 is an efficient relaxant of O2(X 3sigma(g)- and that the propensity rule for O2 relaxation suggested by Mack et al. (J. A. Mack, K. Mikulecky and A. M. Wodtke, J. Chem. Phys., 1996, 105, 4105) has been observed experimentally.
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Affiliation(s)
- Katsuyoshi Yamasaki
- Department of Chemistry, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan.
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18
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Dayou F, Hernández MI, Campos-Martínez J, Hernández-Lamoneda R. Spin-orbit coupling in O2(υ)+O2 collisions: I. Electronic structure calculations on dimer states involving the XΣg−3, aΔg1, and bΣg+1 states of O2. J Chem Phys 2005; 123:074311. [PMID: 16229574 DOI: 10.1063/1.2000253] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The importance of vibrational-to-electronic (V-E) energy transfer mediated by spin-orbit coupling in the collisional removal of O2(X 3Sigmag-,upsilon>or=26) by O2 has been reported in a recent communication [F. Dayou, J. Campos-Martinez, M. I. Hernandez, and R. Hernandez-Lamoneda, J. Chem. Phys. 120, 10355 (2004)]. The present work provides details on the electronic properties of the dimer (O2)2 relevant to the self-relaxation of O2(X 3Sigmag-,upsilon>>0) where V-E energy transfer involving the O2(a 1Deltag) and O2(b 1Sigmag+) states is incorporated. Two-dimensional electronic structure calculations based on highly correlated ab initio methods have been carried out for the potential-energy and spin-orbit coupling surfaces associated with the ground singlet and two low-lying excited triplet states of the dimer dissociating into O2(X 3Sigmag-)+O2(X 3Sigmag-), O2(a 1Deltag)+O2(X 3Sigmag-), and O2(b 1Sigmag+)+O2(X 3Sigmag-). The resulting interaction potentials for the two excited triplet states display very similar features along the intermolecular separation, whereas differences arise with the ground singlet state for which the spin-exchange interaction produces a shorter equilibrium distance and higher binding energy. The vibrational dependence is qualitatively similar for the three studied interaction potentials. The spin-orbit coupling between the ground and second excited states is already nonzero in the O2+O2 dissociation limit and keeps its asymptotic value up to relatively short intermolecular separations, where the coupling increases for intramolecular distances close to the equilibrium of the isolated diatom. On the other hand, state mixing between the two excited triplet states leads to a noticeable collision-induced spin-orbit coupling between the ground and first excited states. The results are discussed in terms of specific features of the dimer electronic structure (including a simple four-electron model) and compared with existing theoretical and experimental data. This work gives theoretical insight into the origin of electronic energy-transfer mechanisms in O2+O2 collisions.
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Affiliation(s)
- Fabrice Dayou
- Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique, Unité Mixte de Recherche (UMR) 8112 du Centre National de la Recherche Scientifique (CNRS), Observatoire de Paris-Meudon, 92195 Meudon Cedex, France.
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Caridade PJSB, Llanio-Trujillo JL, Varandas AJC. Nascent versus “Steady-State” Rovibrational Distributions in the Products of the O(3P) + O3(X̃A) Reaction. J Phys Chem A 2003. [DOI: 10.1021/jp030756v] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | | | - A. J. C. Varandas
- Departamento de Química, Universidade de Coimbra, 3004-535 Coimbra, Portugal
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Slanger TG, Copeland RA. Energetic Oxygen in the Upper Atmosphere and the Laboratory. Chem Rev 2003; 103:4731-66. [PMID: 14664631 DOI: 10.1021/cr0205311] [Citation(s) in RCA: 203] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Tom G Slanger
- Molecular Physics Laboratory, SRI International, Menlo Park, CA 94025, USA
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Caridade PJSB, Sabin J, Garrido JD, Varandas AJC. Dynamics of OH + O2vibrational relaxation processes. Phys Chem Chem Phys 2002. [DOI: 10.1039/b203101a] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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22
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Caridade PJSB, Betancourt M, Garrido JD, Varandas AJC. Dynamics Study of the OH + O2 Branching Atmospheric Reaction. 3. Dissociation in Collisions of Vibrationally Excited Reactants. J Phys Chem A 2001. [DOI: 10.1021/jp010291d] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- P. J. S. B. Caridade
- Departamento de Química, Universidade de Coimbra, P-3049 Coimbra Codex, Portugal
| | - M. Betancourt
- Departamento de Química, Universidade de Coimbra, P-3049 Coimbra Codex, Portugal
| | - J. D. Garrido
- Departamento de Química, Universidade de Coimbra, P-3049 Coimbra Codex, Portugal
| | - A. J. C. Varandas
- Departamento de Química, Universidade de Coimbra, P-3049 Coimbra Codex, Portugal
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Silva M, Jongma R, Field RW, Wodtke AM. The dynamics of "stretched molecules": experimental studies of highly vibrationally excited molecules with stimulated emission pumping. Annu Rev Phys Chem 2001; 52:811-52. [PMID: 11326081 DOI: 10.1146/annurev.physchem.52.1.811] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We review stimulated emission pumping as used to study molecular dynamics. The review presents unimolecular as well as scattering studies. Topics include intramolecular vibrational redistribution, unimolecular isomerization and dissociation, van der Waals clusters, rotational energy transfer, vibrational energy transfer, gas-surface interactions, atmospheric effects resulting from nonequilibrium vibrational excitation, and vibrational promotion of electron transfer.
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Affiliation(s)
- M Silva
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, Massachusetts 02139, USA.
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Légaré F, Chelkowski S, Bandrauk A. Preparation and alignment of highly vibrationally excited molecules by CARP – chirped adiabatic Raman passage. Chem Phys Lett 2000. [DOI: 10.1016/s0009-2614(00)01040-x] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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25
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Hernández-Lamoneda R, Ramı́rez-Solı́s A. Reactivity and electronic states of O4 along minimum energy paths. J Chem Phys 2000. [DOI: 10.1063/1.1288370] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
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