1
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Chen L, Ma Z, Fournier JA. Ultrafast transient vibrational action spectroscopy of cryogenically cooled ions. J Chem Phys 2023; 159:041101. [PMID: 37486043 DOI: 10.1063/5.0155490] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Accepted: 05/25/2023] [Indexed: 07/25/2023] Open
Abstract
Ultrafast transient vibrational action spectra of cryogenically cooled Re(CO)3(CH3CN)3+ ions are presented. Nonlinear spectra were collected in the time domain by monitoring the photodissociation of a weakly bound N2 messenger tag as a function of delay times and phases between a set of three infrared pulses. Frequency-resolved spectra in the carbonyl stretch region show relatively strong bleaching signals that oscillate at the difference frequency between the two observed vibrational features as a function of the pump-probe waiting time. This observation is consistent with the presence of nonlinear pathways resulting from underlying cross-peak signals between the coupled symmetric-asymmetric C≡O stretch pair. The successful demonstration of frequency-resolved ultrafast transient vibrational action spectroscopy of dilute molecular ion ensembles provides an exciting, new framework for the study of molecular dynamics in isolated, complex molecular ion systems.
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Affiliation(s)
- Liangyi Chen
- Department of Chemistry, Washington University in St. Louis, St. Louis, Missouri 63130, USA
| | - Zifan Ma
- Department of Chemistry, Washington University in St. Louis, St. Louis, Missouri 63130, USA
| | - Joseph A Fournier
- Department of Chemistry, Washington University in St. Louis, St. Louis, Missouri 63130, USA
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2
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Karmakar S, Keshavamurthy S. Intramolecular vibrational energy redistribution and the quantum ergodicity transition: a phase space perspective. Phys Chem Chem Phys 2020; 22:11139-11173. [DOI: 10.1039/d0cp01413c] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The onset of facile intramolecular vibrational energy flow can be related to features in the connected network of anharmonic resonances in the classical phase space.
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Affiliation(s)
- Sourav Karmakar
- Department of Chemistry
- Indian Institute of Technology
- Kanpur
- India
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3
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Diroll BT, Mannodi-Kanakkithodi A, Chan MKY, Schaller RD. Spectroscopic Comparison of Thermal Transport at Organic-Inorganic and Organic-Hybrid Interfaces Using CsPbBr 3 and FAPbBr 3 (FA = Formamidinium) Perovskite Nanocrystals. NANO LETTERS 2019; 19:8155-8160. [PMID: 31603685 DOI: 10.1021/acs.nanolett.9b03502] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Thermal transport across interfaces depends on the matching of vibrational structure at the interface. This work examines the transfer of thermal excitation from an organic ligand coating to either all-inorganic cesium lead tribromide (CsPbBr3) nanocrystals or hybrid organic-inorganic formamidinium lead tribromide (FAPbBr3) nanocrystals using selective infrared optical excitation. These two semiconductors are directly compared because they (or similar semiconductors) are currently envisioned as strong candidates in many optoelectronic technologies and they differ due to the presence of an organic or inorganic cation, which introduces substantial differences in the phonon density of states in otherwise quite similar semiconductors. Infrared excitation of C-H vibrations of surface-bound ligands generates a temperature gradient between the organic ligand shell and nanocrystal core, which results in heat flow, measured by probing changes of the semiconductor band gap. Heat transfer to both perovskite compositions of comparable sizes is similar (25-30 ps), due to fast intramolecular vibrational relaxation and similar matching of low-energy phonons with the organic ligand, but FAPbBr3 samples show a slow bleaching kinetic on the order of 1 ns. This slow, heat-induced change in the semiconductor band gap is attributed not to interfacial heat transfer but instead to thermal equilibration between the organic and inorganic sublattices of FAPbBr3. Ab initio molecular dynamics simulations support the hypothesis that low-energy inorganic sublattice phonon modes are populated initially in the heat transfer process, with a slow thermal population of the higher-energy phonon modes associated primarily with the organic cation. Slow thermal equilibration of FAPbBr3 is likely to substantially impact the time-dependent response of optoelectronic devices that heat the semiconductor active layer and provide further evidence that the poor bulk thermal transport of hybrid perovskite materials extends to microscopic thermal processes.
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Affiliation(s)
- Benjamin T Diroll
- Center for Nanoscale Materials , Argonne National Laboratory , 9700 South Cass Avenue , Lemont , Illinois 60439 , United States
| | - Arun Mannodi-Kanakkithodi
- Center for Nanoscale Materials , Argonne National Laboratory , 9700 South Cass Avenue , Lemont , Illinois 60439 , United States
| | - Maria K Y Chan
- Center for Nanoscale Materials , Argonne National Laboratory , 9700 South Cass Avenue , Lemont , Illinois 60439 , United States
| | - Richard D Schaller
- Center for Nanoscale Materials , Argonne National Laboratory , 9700 South Cass Avenue , Lemont , Illinois 60439 , United States
- Department of Chemistry , Northwestern University , 2145 Sheridan Avenue , Evanston , Illinois 60208 , United States
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4
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Carr PJJ, Lecours MJ, Burt MJ, Marta RA, Steinmetz V, Fillion E, Hopkins WS. Mode-Selective Laser Control of Palladium Catalyst Decomposition. J Phys Chem Lett 2018; 9:157-162. [PMID: 29244504 DOI: 10.1021/acs.jpclett.7b03030] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
It is generally assumed that molecules behave ergodically during chemical reactions, that is, reactivities depend only on the total energy content and not on the initial state of the molecule. While there are a few examples of nonergodic behavior in small (usually electronically excited) species, to date there have been no reports of such behavior in larger covalently bound species composed of several tens of atoms. Here, we demonstrate vibrational mode-selective behavior in a series of palladium catalysts. When we excite solvent-tagged gas-phase Pd catalysts with an infrared laser that is tuned to be resonant with specific molecular vibrations, depending on which vibration we excite, we can select different reaction pathways. We also demonstrate that this behavior can be "turned off" via chemical substitution.
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Affiliation(s)
- Patrick J J Carr
- Department of Chemistry, University of Waterloo , Waterloo, ON N2L 3G1, Canada
| | - Michael J Lecours
- Department of Chemistry, University of Waterloo , Waterloo, ON N2L 3G1, Canada
| | - Michael J Burt
- Department of Chemistry, University of Waterloo , Waterloo, ON N2L 3G1, Canada
| | - Rick A Marta
- Department of Chemistry, University of Waterloo , Waterloo, ON N2L 3G1, Canada
| | - Vincent Steinmetz
- Laboratoire Chemie Physique, CLIO/LCP , Bâtiment 201, Campus Universitaire d'Orsay, Orsay 91405, France
| | - Eric Fillion
- Department of Chemistry, University of Waterloo , Waterloo, ON N2L 3G1, Canada
| | - W Scott Hopkins
- Department of Chemistry, University of Waterloo , Waterloo, ON N2L 3G1, Canada
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5
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Kushnarenko A, Miloglyadov E, Quack M, Seyfang G. Intramolecular vibrational energy redistribution in HCCCH2X (X = Cl, Br, I) measured by femtosecond pump–probe experiments in a hollow waveguide. Phys Chem Chem Phys 2018; 20:10949-10959. [DOI: 10.1039/c7cp08561c] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Time resolved femtosecond probing of intramolecular energy flow after excitation of the two different infrared CH-chromophores in these bichromophoric molecules shows strong dependence on the chemical environment of the initial excitation.
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Affiliation(s)
- Alexander Kushnarenko
- ETH Zurich, Lab. für Physikalische Chemie
- HCI E235
- Vladimir-Prelog-Weg 1-5/10
- 8093 Zurich
- Switzerland
| | - Eduard Miloglyadov
- ETH Zurich, Lab. für Physikalische Chemie
- HCI E235
- Vladimir-Prelog-Weg 1-5/10
- 8093 Zurich
- Switzerland
| | - Martin Quack
- ETH Zurich, Lab. für Physikalische Chemie
- HCI E235
- Vladimir-Prelog-Weg 1-5/10
- 8093 Zurich
- Switzerland
| | - Georg Seyfang
- ETH Zurich, Lab. für Physikalische Chemie
- HCI E235
- Vladimir-Prelog-Weg 1-5/10
- 8093 Zurich
- Switzerland
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6
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Chekalin SV, Kompanets VO, Koshlyakov PV, Laptev VB, Pigulsky SV, Makarov AA, Ryabov EA. Intramolecular vibrational dynamics in free polyatomic molecules with C═O chromophore bond excited by resonant femtosecond IR laser radiation. J Phys Chem A 2014; 118:955-64. [PMID: 24467228 DOI: 10.1021/jp407131x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
In nine polyatomic molecules, we have studied the intramolecular redistribution of vibrational energy from chromophore C═O group excited by a resonant femtosecond IR laser radiation at a wavelength of ∼5 μm. All experiments have been performed in the gas phase using the IR-IR pump-probe technique in combination with the spectral analysis of the probe radiation. For molecules with one C═O end group, characteristic times of intramolecular vibrational redistribution (IVR) lie in the range between 2.4 and 20 ps and correlate with the density of four-frequency Fermi resonances. The IVR times in metal carbonyl molecules are anomalously long, being ∼1.0 ns for Fe(CO)5 and ∼1.5 ns for Cr(CO)6. In the CH3(C═O)OC2H5 and H2CCH(C═O)OC2H5 molecules, it has been observed that there are two characteristic IVR times, which differ by an order of magnitude from each other; this was interpreted in terms of the developed model of "accumulating states". For the ICF2COF molecule, it has been revealed that the IVR time decreases with increasing level of the vibrational excitation of the C═O bond of the molecule.
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Affiliation(s)
- Sergey V Chekalin
- Institute of Spectroscopy, Russian Academy of Sciences , Fizicheskaya street, 5, Troitsk, Moscow 142190, Russia
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7
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Quantum-State Resolved Gas/Surface Reaction Dynamics Experiments. DYNAMICS OF GAS-SURFACE INTERACTIONS 2013. [DOI: 10.1007/978-3-642-32955-5_8] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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8
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Herman M, Perry DS. Molecular spectroscopy and dynamics: a polyad-based perspective. Phys Chem Chem Phys 2013; 15:9970-93. [DOI: 10.1039/c3cp50463h] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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9
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Killelea DR, Utz AL. On the origin of mode- and bond-selectivity in vibrationally mediated reactions on surfaces. Phys Chem Chem Phys 2013; 15:20545-54. [DOI: 10.1039/c3cp53765j] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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10
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Shaffer CJ, Révész Á, Schröder D, Severa L, Teplý F, Zins EL, Jašíková L, Roithová J. Can Hindered Intramolecular Vibrational Energy Redistribution Lead to Non-Ergodic Behavior of Medium-Sized Ion Pairs? Angew Chem Int Ed Engl 2012; 51:10050-3. [DOI: 10.1002/anie.201203441] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2012] [Indexed: 11/06/2022]
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11
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Shaffer CJ, Révész Á, Schröder D, Severa L, Teplý F, Zins EL, Jašíková L, Roithová J. Kann gehinderter intramolekularer Schwingungsenergietransfer nichtergodisches Verhalten mittelgroßer Ionenpaare bewirken? Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201203441] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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12
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Twagirayezu S, Wang X, Perry DS, Neill JL, Muckle MT, Pate BH, Xu LH. IR and FTMW-IR Spectroscopy and Vibrational Relaxation Pathways in the CH Stretch Region of CH3OH and CH3OD. J Phys Chem A 2011; 115:9748-63. [DOI: 10.1021/jp202020u] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | - Xiaoliang Wang
- Department of Chemistry, The University of Akron, Akron, Ohio 44325, United States
| | - David S. Perry
- Department of Chemistry, The University of Akron, Akron, Ohio 44325, United States
| | - Justin L. Neill
- Department of Chemistry, University of Virginia, McCormick Road, Charlottesville, Virginia 22904, United States
| | - Matt T. Muckle
- Department of Chemistry, University of Virginia, McCormick Road, Charlottesville, Virginia 22904, United States
| | - Brooks H. Pate
- Department of Chemistry, University of Virginia, McCormick Road, Charlottesville, Virginia 22904, United States
| | - Li-Hong Xu
- Department of Physics, Centre for Laser, Atomic and Molecular Studies (CLAMS), University of New Brunswick, Saint John, New Brunswick E2L 4L5, Canada
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13
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King AK, Bellm SM, Hammond CJ, Reid KL, Towrie M, Matousek P. Picosecond time-resolved photoelectron spectroscopy as a means of elucidating mechanisms of intramolecular vibrational energy redistribution in electronically excited states of small aromatic molecules. Mol Phys 2011. [DOI: 10.1080/00268970500096103] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Adrian K. King
- a School of Chemistry , University of Nottingham , Nottingham , NG7 2RD , UK
| | - Susan M. Bellm
- a School of Chemistry , University of Nottingham , Nottingham , NG7 2RD , UK
| | - Chris J. Hammond
- a School of Chemistry , University of Nottingham , Nottingham , NG7 2RD , UK
| | - Katharine L. Reid
- a School of Chemistry , University of Nottingham , Nottingham , NG7 2RD , UK
| | - Michael Towrie
- b Lasers for Science Facility, CCLRC , Rutherford Appleton Laboratory , Oxon , OX11 0QX , UK
| | - Pavel Matousek
- b Lasers for Science Facility, CCLRC , Rutherford Appleton Laboratory , Oxon , OX11 0QX , UK
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14
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von Benten RS, Abel B. On the nature of intramolecular vibrational energy transfer in dense molecular environments. Chem Phys 2010. [DOI: 10.1016/j.chemphys.2010.09.009] [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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15
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Twagirayezu S, Clasp TN, Perry DS, Neill JL, Muckle MT, Pate BH. Vibrational Coupling Pathways in Methanol As Revealed by Coherence-Converted Population Transfer Fourier Transform Microwave Infrared Double-Resonance Spectroscopy. J Phys Chem A 2010; 114:6818-28. [DOI: 10.1021/jp1019735] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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16
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Adams CL, Schneider H, Weber JM. Vibrational Autodetachment−Intramolecular Vibrational Relaxation Translated into Electronic Motion. J Phys Chem A 2010; 114:4017-30. [DOI: 10.1021/jp910675n] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- C. L. Adams
- JILA, NIST, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309
| | - H. Schneider
- JILA, NIST, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309
| | - J. M. Weber
- JILA, NIST, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309
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17
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Lee JH, Hwang H, Kwon CH, Kim HL. Photodissociation Dynamics of Propargyl Alcohol at 212 nm: The OH Production Channel. J Phys Chem A 2010; 114:2053-8. [DOI: 10.1021/jp9091865] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Ji Hye Lee
- Department of Chemistry, Institute for Molecular Science and Fusion Technology, Kangwon National University, Chunchun 200-701, South Korea
| | - Hyonseok Hwang
- Department of Chemistry, Institute for Molecular Science and Fusion Technology, Kangwon National University, Chunchun 200-701, South Korea
| | - Chan Ho Kwon
- Department of Chemistry, Institute for Molecular Science and Fusion Technology, Kangwon National University, Chunchun 200-701, South Korea
| | - Hong Lae Kim
- Department of Chemistry, Institute for Molecular Science and Fusion Technology, Kangwon National University, Chunchun 200-701, South Korea
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18
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Kim YS, Hochstrasser RM. Applications of 2D IR spectroscopy to peptides, proteins, and hydrogen-bond dynamics. J Phys Chem B 2009; 113:8231-51. [PMID: 19351162 PMCID: PMC2845308 DOI: 10.1021/jp8113978] [Citation(s) in RCA: 246] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Following a survey of 2D IR principles, this article describes recent experiments on the hydrogen-bond dynamics of small ions, amide-I modes, nitrile probes, peptides, reverse transcriptase inhibitors, and amyloid fibrils.
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Affiliation(s)
- Yung Sam Kim
- Department of Chemistry, University of Pennsylvania Philadelphia, Pennsylvania 19104-6323, U.S.A
| | - Robin M. Hochstrasser
- Department of Chemistry, University of Pennsylvania Philadelphia, Pennsylvania 19104-6323, U.S.A
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19
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Ebata T. Study on the Structure and Vibrational Dynamics of Functional Molecules and Molecular Clusters by Double Resonance Vibrational Spectroscopy. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2009. [DOI: 10.1246/bcsj.82.127] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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20
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Sibert EL, Ramesh SG, Gulmen TS. Vibrational Relaxation of OH and CH Fundamentals of Polar and Nonpolar Molecules in the Condensed Phase. J Phys Chem A 2008; 112:11291-305. [DOI: 10.1021/jp8068442] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Edwin L. Sibert
- Department of Chemistry and Theoretical Chemistry Institute, University of Wisconsin—Madison, Madison, Wisconsin 53706
| | - Sai G. Ramesh
- Department of Chemistry and Theoretical Chemistry Institute, University of Wisconsin—Madison, Madison, Wisconsin 53706
| | - Tolga S. Gulmen
- Department of Chemistry and Theoretical Chemistry Institute, University of Wisconsin—Madison, Madison, Wisconsin 53706
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21
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Sharp EN, Roberts MA, Nesbitt DJ. Rotationally resolved infrared spectroscopy of a jet-cooled phenyl radical in the gas phase. Phys Chem Chem Phys 2008; 10:6592-6. [PMID: 18989469 DOI: 10.1039/b813256a] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The first high-resolution IR spectra of a jet-cooled phenyl radical are reported, obtained via direct absorption laser spectroscopy in a slit-jet discharge supersonic expansion. The observed A-type band arises from fundamental excitation of the out-of-phase symmetric CH stretch mode (nu19) of b2 symmetry. Unambiguous spectral assignment of the rotational structure to the phenyl radical is facilitated by comparison with precision 2-line combination differences from Fourier transform microwave and direct absorption mm-wave measurements on the ground state [R. J. McMahon et al., Astrophys. J., 2003, 590, L61]. Least-squares fits to an asymmetric top Hamiltonian permit the upper-state rotational constants to be obtained. The corresponding gas-phase vibrational band origin at 3071.8904 (10) cm(-1) is in remarkably good agreement with previous matrix isolation studies [A. V. Friderichsen et al., J. Am. Chem. Soc., 2001, 123, 1977], and indicates only a relatively minor red shift (approximately 0.9 cm(-1)) between the gas and Ar matrix phase environment. Such studies offer considerable promise for further high resolution IR study of other aromatic radical species of particular relevance to combustion phenomena and interstellar chemistry.
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Affiliation(s)
- Erin N Sharp
- JILA, National Institute of Standards and Technology, University of Colorado, Boulder, Colorado 80309, USA
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22
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Makarov AA, Malinovsky AL, Ryabov EA. A novel feature of intramolecular vibrational redistribution in propargyl alcohol and propargyl amine. J Chem Phys 2008; 129:116102. [DOI: 10.1063/1.2977982] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
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23
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Schneider H, Vogelhuber KM, Schinle F, Stanton JF, Weber JM. Vibrational Spectroscopy of Nitroalkane Chains Using Electron Autodetachment and Ar Predissociation. J Phys Chem A 2008; 112:7498-506. [DOI: 10.1021/jp800124s] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Holger Schneider
- JILA, NIST, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309, and Department of Chemistry and Biochemistry, University of Texas at Austin, 1 University Station A5300, Austin, TX 78712-0165
| | - Kristen M. Vogelhuber
- JILA, NIST, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309, and Department of Chemistry and Biochemistry, University of Texas at Austin, 1 University Station A5300, Austin, TX 78712-0165
| | - Florian Schinle
- JILA, NIST, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309, and Department of Chemistry and Biochemistry, University of Texas at Austin, 1 University Station A5300, Austin, TX 78712-0165
| | - John F. Stanton
- JILA, NIST, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309, and Department of Chemistry and Biochemistry, University of Texas at Austin, 1 University Station A5300, Austin, TX 78712-0165
| | - J. Mathias Weber
- JILA, NIST, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309, and Department of Chemistry and Biochemistry, University of Texas at Austin, 1 University Station A5300, Austin, TX 78712-0165
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24
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Barnes GL, Sibert EL. Elucidating energy disposal pathways following excitation of the symmetric OH stretching band in formic acid dimer. Chem Phys Lett 2008. [DOI: 10.1016/j.cplett.2008.05.090] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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25
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Kim T, Felker PM. Vibrational spectroscopy and dynamics in the CH-stretch region of fluorene by IVR-assisted, ionization-gain stimulated Raman spectroscopy. J Phys Chem A 2007; 111:12466-70. [PMID: 17924611 DOI: 10.1021/jp075053i] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
We report stimulated Raman spectra at 0.2 and 0.03 cm(-1) resolution in the CH-stretching region of jet-cooled fluorene. The results were obtained by a version of ionization-gain stimulated Raman spectroscopy in which resonant two-photon ionization probing of the state-population changes arising from stimulated Raman transitions is assisted by the process of intramolecular vibrational redistribution (IVR) in the Raman-excited molecule. The fluorene spectra reveal extensive vibrational coupling interactions involving both the aliphatic and aromatic CH-stretching first excited states with nearby background states. Results pertaining to the symmetric aliphatic CH-stretching fundamental are consistent with a tier model of IVR and point to vibrational energy flow out of the CH stretch on a approximately 1 ps time scale with subsequent redistribution on a approximately 5 ps time scale.
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Affiliation(s)
- Taiho Kim
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, USA
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26
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Gulmen TS, Sibert EL. Vibrational energy relaxation of the OH(D) stretch fundamental of methanol in carbon tetrachloride. J Chem Phys 2007; 123:204508. [PMID: 16351282 DOI: 10.1063/1.2131055] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The lifetimes of the hydroxyl stretch fundamentals of two methanol isotopomers, MeOH and MeOD, in carbon tetrachloride solvent are calculated through the use of the perturbative Landau-Teller and fluctuating Landau-Teller methods. Examination of these systems allows for insight into the nature of the vibrational couplings that lead to intramolecular vibrational energy transfer. While both systems display energy transfer to nearly degenerate modes, MeOD also displays strong coupling to an off-resonant vibration. The relaxation of MeOH and MeOD occurs through transitions involving a total change in the vibrational quanta of 4 and 3, respectively. We calculate vibrational energy relaxation lifetimes of 4-5 ps for MeOH and 2-3 ps for MeOD that agree well with the experimentally determined values.
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Affiliation(s)
- Tolga S Gulmen
- Department of Chemistry and Theoretical Chemistry Institute, University of Wisconsin-Madison, Madison, WI 53706, USA
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27
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Shipman ST, Douglass PC, Yoo HS, Hinkle CE, Mierzejewski EL, Pate BH. Vibrational dynamics of carboxylic acid dimers in gas and dilute solution. Phys Chem Chem Phys 2007; 9:4572-86. [PMID: 17690783 DOI: 10.1039/b704900e] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Ultrafast mid-IR transient absorption spectroscopy has been used to study the vibrational dynamics of hydrogen-bonded cyclic dimers of trifluoroacetic acid and formic acid in both the gas and solution phases (0.05 M in CCl(4)). Ultrafast excitation of the broad O-H cyclic dimer band leads, in the gas phase, to large-scale structural changes of the dimer creating a species with a distinct free O-H stretching band on 20 ps and 200 ps timescales. These timescales are assigned to ring-opening and dissociation of the dimer, respectively. In the solution phase, no such structural rearrangement occurs and our results are consistent with previous studies. The gas phase dynamics are insensitive to both the specific excitation energy (over a span of 550 cm(-1)) and the chemical identity of the dimer.
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Affiliation(s)
- Steven T Shipman
- Department of Chemistry, University of Virginia, Charlottesville, VA 22904, USA
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Gündoğdu K, Nydegger MW, Bandaria JN, Hill SE, Cheatum CM. Vibrational relaxation of C-D stretching vibrations in CDCl3, CDBr3, and CDI3. J Chem Phys 2007; 125:174503. [PMID: 17100450 DOI: 10.1063/1.2361288] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
We present time-resolved transient grating measurements of the vibrational relaxation rates of the C-D stretching vibrations of deuterated haloforms in benzene and acetone. We compare our results with previous measurements of excited C-H stretches in the same solvents to obtain insight into the solvent effect on the vibrational relaxation. In deuterated molecules, there are more low-order-coupled states and the states are closer in energy to the C-D stretch than in the unlabeled isotopologs. Therefore, the relaxation is faster for the deuterated molecules. The relaxation also shows a significant solvent dependence. Bromoform and iodoform form charge-transfer complexes with both benzene and acetone which enhance the relaxation rate. For chloroform, hydrogen bonding to acetone is expected to be a more favorable interaction. Surprisingly, however, the vibrational relaxation of CDCl(3) is slower in acetone than in benzene.
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Affiliation(s)
- Kenan Gündoğdu
- Chemistry Department, The University of Iowa, Iowa City, IA 52242, USA
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29
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Yamada Y, Katsumoto Y, Ebata T. Picosecond IR-UV pump–probe spectroscopic study on the vibrational energy flow in isolated molecules and clusters. Phys Chem Chem Phys 2007; 9:1170-85. [PMID: 17325763 DOI: 10.1039/b614895f] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Intramolecular vibrational energy redistribution (IVR) and vibrational predissociation (VP) from the XH stretching vibrations, where X refers to O or C atom, of aromatic molecules and their hydrogen(H)-bonded clusters are investigated by picosecond time-resolved IR-UV pump probe spectroscopy in a supersonic beam. For bare molecules, we mainly focus on IVR of the OH stretch of phenol. We describe the IVR of the OH stretch by a two-step tier model and examine the effect of the anharmonic coupling strength and the density of states on IVR rate and mechanism by using isotope substitution. In the H-bonded clusters of phenol, we show that the relaxation of the OH stretching vibration can be described by a stepwise process and then discuss which process is sensitive to the H-bonding strength. We discuss the difference/similarity of IVR/VP between the "donor" and the "acceptor" sites in phenol-ethylene cluster by exciting the CH stretch vibrations. Finally, we study the vibrational energy transfer in the isolated molecules having the alkyl chain, namely phenylalcanol (PA). In this system, we measure the rate constant of the vibrational energy transfer between the OH stretch and the vibrations of benzene ring which are connected at the both ends of the alkyl chain. This energy transfer can be called "through-bond IVR". We investigate the three factors which are thought to control the energy transfer rate; (1) "OH <--> next CH(2)" coupling, (2) chain length and (3) conformation. We discuss the energy transfer mechanism in PAs by examining these factors.
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Affiliation(s)
- Yuji Yamada
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai, 980-8578, Japan
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30
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Ramesh SG, Sibert EL. Relaxation of the CH stretch in liquid CHBr3: Solvent effects and decay rates using classical nonequilibrium simulations. J Chem Phys 2006; 125:244513. [PMID: 17199361 DOI: 10.1063/1.2403876] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
This article addresses two questions regarding the decay of the CH stretch in liquid CHBr3. The first is whether the initial steps of the relaxation primarily involve energy redistribution within the excited molecule alone. Gas phase quantum mechanical and classical calculations are performed to examine the role of the solvent in this process. At the fundamental excitation level, it is found that CH stretch decay is, in fact, strongly solvent driven. The second question is on the applicability of a fully classical approach to the calculation of CH stretch condensed phase decay rates. To this end, nonequilibrium molecular dynamics simulations are performed. The results are compared with quantum mechanical rates computed previously. The two methods are found to be in fair agreement with each other. However, care must be exercised in the interpretation of the classical results.
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Affiliation(s)
- Sai G Ramesh
- Department of Chemistry, and Theoretical Chemistry Institute, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
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31
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Ramesh SG, Sibert EL. Vibrational relaxation of the CH stretch fundamental in liquid CHBr3. J Chem Phys 2006; 124:234501. [PMID: 16821923 DOI: 10.1063/1.2202353] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
In continuation of our work on haloforms, the decay of CH stretch excitation in bromoform is modeled using molecular dynamics simulations. An intermolecular force field is obtained by fitting ab initio energies at select CHBr3 dimer geometries to a potential function. The solvent forces on vibrational modes obtained in the simulation are used to compute relaxation rates. The Landau-Teller approach points to a single acceptor state in the initial step of CH stretch relaxation. The time scale for this process is found to be 50-90 ps, which agrees well with the experimental value of 50 ps. The reason for the selectivity of the acceptor is elaborated. Results from a time-dependent approach to the decay rates are also discussed.
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Affiliation(s)
- Sai G Ramesh
- Theoretical Chemistry Institute, Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
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Abstract
▪ Abstract Modern ultrafast spectroscopic techniques provide new opportunities to study chemical reaction dynamics in liquids and hold the possibility of obtaining much of the same detailed information available in gases. Vibrational energy transfer studies are the most advanced of the investigations and demonstrate that it is possible to observe state-specific pathways of energy flow within a vibrationally excited molecule (intramolecular vibrational relaxation) and into the surrounding solvent molecules (intermolecular energy transfer). Energy transfer in liquids and gases share many common aspects, but the presence of the solvent also alters the relaxation in both obvious and subtle ways. Photodissociation is amenable to similarly detailed study in liquids, and there are informative new measurements. Bimolecular reactions have received the least attention in state-resolved measurements in liquids, but the means to carry them much further now exist. Studying photodissociation and bimolecular reaction of molecules prepared with initial vibrational excitation in liquids is a realistic, but challenging, goal.
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Affiliation(s)
- Christopher G Elles
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, USA.
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33
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Yamada Y, Kayano M, Mikami N, Ebata T. Picosecond IR−UV Pump−Probe Study on the Vibrational Relaxation of Phenol−Ethylene Hydrogen-Bonded Cluster: Difference of Relaxation Route/Rate between the Donor and the Acceptor Site Excitations. J Phys Chem A 2006; 110:6250-5. [PMID: 16686458 DOI: 10.1021/jp0571832] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Picosecond time-resolved IR-UV pump-probe spectroscopy has been performed to study intracluster vibrational energy redistribution (ICVR) and vibrational predissociation (VP) for the OH and CH stretch vibrations of phenol-ethylene hydrogen-bonded cluster. The transient UV spectra after the picosecond IR pulse excitation of these modes were observed by 1+1 REMPI via S(1) with a picosecond UV pulse. We have focused on the difference of the energy flow routes and their rates between the donor (phenol) and the acceptor (ethylene) site. Though the transient UV spectra showed a similar broad feature for all the vibrations examined, the time profiles exhibited a remarkable site dependence, as well as substantial mode dependence. Especially, we found a large difference in the early stage of the IVR evolution and the rates, whereas the VP rates were very similar.
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Affiliation(s)
- Yuji Yamada
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578 Japan
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34
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Malinovsky A, Doljikov Y, Makarov A, Ogurok ND, Ryabov E. Dynamics of intramolecular vibrational redistribution in propargylchloride molecule studied by time-resolved Raman spectroscopy. Chem Phys Lett 2006. [DOI: 10.1016/j.cplett.2005.12.019] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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35
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Cox MJ, Crim FF. Vibrational Energy Flow Rates for cis- and trans-Stilbene Isomers in Solution. J Phys Chem A 2005; 109:11673-8. [PMID: 16366616 DOI: 10.1021/jp054263x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Transient electronic absorption following excitation of the first C-H stretching overtone (2nu(CH)) or a C-H stretch-bend combination (nu(CH) + nu(bend)) monitors the flow of vibrational energy in cis-stilbene and in trans-stilbene. Following a rapid initial rise as energy flows into states interrogated by the probe pulse, the absorption decays with two time constants, which are about a factor of 2 longer for the cis-isomer than for the trans-isomer. The decay times for cis-stilbene are tau2(cis) = (2.6 +/- 1.5) ps and tau3(cis) = (24.1 +/- 2.1) ps, and those for trans-stilbene are tau2(trans) = (1.4 +/- 0.6) ps and tau3(trans) = (10.2 +/- 1.1) ps. The decay times are essentially the same in different solvents, suggesting that the relaxation is primarily intramolecular. The two decay times are consistent with the sequential flow of energy through sets of coupled states within the molecule, and the difference in the rates for the two isomers likely reflects differences in coupling among the states arising from the different structures of the isomers. The similarity of the time evolution following excitation of the first C-H overtone at 5990 cm(-1) and the stretch-bend combination at 4650 cm(-1) is consistent with a subset of states, whose structure is similar for the two vibrational excitation energies, controlling the observed flow of energy.
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Affiliation(s)
- M Jocelyn Cox
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
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36
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Yamada Y, Okano JI, Mikami N, Ebata T. Picosecond IR-UV pump-probe spectroscopic study on the intramolecular vibrational energy redistribution of NH2 and CH stretching vibrations of jet-cooled aniline. J Chem Phys 2005; 123:124316. [PMID: 16392491 DOI: 10.1063/1.2039087] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Intramolecular vibrational energy redistribution (IVR) of the NH2 symmetric and asymmetric stretching vibrations of jet-cooled aniline has been investigated by picosecond time-resolved IR-UV pump-probe spectroscopy. A picosecond IR laser pulse excited the NH2 symmetric or asymmetric stretching vibration of aniline in the electronic ground state and the subsequent time evolutions of the excited level as well as redistributed levels were observed by a picosecond UV pulse. The IVR lifetimes for symmetric and asymmetric stretches were obtained to be 18 and 34 ps, respectively. In addition, we obtained the direct evidence that IVR proceeds via two-step bath states; that is, the NH2 stretch energy first flows into the doorway state and the energy is further dissipated into dense bath states. The rate constants of the second step were estimated to be comparable to or slower than those of the first step IVR. The relaxation behavior was compared with that of IVR of the OH stretching vibration of phenol [Y. Yamada, T. Ebata, M. Kayano, and M. Mikami J. Chem. Phys. 120, 7400 (2004)]. We found that the second step IVR process of aniline is much slower than that of phenol, suggesting a large difference of the "doorway state increasing the dense bath states" anharmonic coupling strength between the two molecules. We also observed IVR of the CH stretching vibrations, which showed much faster IVR behavior than that of the NH2 stretches. The fast relaxation is described by the interference effect, which is caused by the coherent excitation of the quasistationary states.
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Affiliation(s)
- Yuji Yamada
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan
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37
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Payne MA, Milce AP, Frost MJ, Orr BJ. Rovibrational Energy Transfer in the 4νCH Manifold of Acetylene Viewed by IR−UV Double Resonance Spectroscopy. 2. Perturbed States with J = 17 and 18. J Phys Chem B 2005; 109:8332-43. [PMID: 16851977 DOI: 10.1021/jp0463518] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Collision-induced state-to-state molecular energy transfer between rovibrational states in the 12,700 cm(-1) 4nu(CH) manifold of the electronic ground state X of acetylene (C(2)H(2)) is monitored by time-resolved infrared-ultraviolet double resonance (IR-UV DR) spectroscopy. Rotational J-states associated with the (nu(1) + 3nu(3)) or (1 0 3 0 0)(0) vibrational combination level, initially prepared by an IR pulse, are probed at approximately 299, approximately 296, or approximately 323 nm with UV laser-induced fluorescence via the Alpha electronic state. The rovibrational J-states of interest belong to a congested manifold that is affected by anharmonic, l-resonance, and Coriolis couplings, yielding complex intramolecular dynamics. Consequently, collision-induced rovibrational satellites observed by IR-UV DR comprise not only regular even-DeltaJ features but also supposedly forbidden odd-DeltaJ features. A preceding paper (J. Phys. Chem. A 2003, 107, 10759) focused on low-J-value rovibrational levels of the 4nu(CH) manifold (particularly those with J = 0 and J = 1) whereas this paper examines locally perturbed states at higher values of J (particularly J = 17 and 18, which display anomalous doublet structure in IR-absorption spectra). Three complementary forms of IR-UV DR experiments (IR-scanned, UV-scanned, and kinetic) are used to address the extent to which intramolecular perturbations influence the efficiency of J-resolved collision-induced energy transfer with both even and odd DeltaJ.
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Affiliation(s)
- Mark A Payne
- Centre for Lasers and Applications, Macquarie University, Sydney, New South Wales 2109, Australia
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38
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Elles CG, Cox MJ, Crim FF. Vibrational relaxation of CH3I in the gas phase and in solution. J Chem Phys 2004; 120:6973-9. [PMID: 15267596 DOI: 10.1063/1.1676292] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Transient electronic absorption measurements reveal the vibrational relaxation dynamics of CH(3)I following excitation of the C-H stretch overtone in the gas phase and in liquid solutions. The isolated molecule relaxes through two stages of intramolecular vibrational relaxation (IVR), a fast component that occurs in a few picoseconds and a slow component that takes place in about 400 ps. In contrast, a single 5-7 ps component of IVR precedes intermolecular energy transfer (IET) to the solvent, which dissipates energy from the molecule in 50 ps, 44 ps, and 16 ps for 1 M solutions of CH(3)I in CCl(4), CDCl(3), and (CD(3))(2)CO, respectively. The vibrational state structure suggests a model for the relaxation dynamics in which a fast component of IVR populates the states that are most strongly coupled to the initially excited C-H stretch overtone, regardless of the environment, and the remaining, weakly coupled states result in a secondary relaxation only in the absence of IET.
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Affiliation(s)
- Christopher G Elles
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
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39
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Yoo HS, DeWitt MJ, Pate BH. Vibrational Dynamics of Terminal Acetylenes: II. Pathway for Vibrational Relaxation in Gas and Solution. J Phys Chem A 2004. [DOI: 10.1021/jp027546n] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Hyun S. Yoo
- Department of Chemistry, University of Virginia, McCormick Road, Charlottesville, Virginia 22904
| | - Merrick J. DeWitt
- Department of Chemistry, University of Virginia, McCormick Road, Charlottesville, Virginia 22904
| | - Brooks H. Pate
- Department of Chemistry, University of Virginia, McCormick Road, Charlottesville, Virginia 22904
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40
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Yoo HS, DeWitt MJ, Pate BH. Vibrational Dynamics of Terminal Acetylenes: I. Comparison of the Intramolecular Vibrational Energy Redistribution Rate of Gases and the Total Relaxation Rate of Dilute Solutions at Room Temperature. J Phys Chem A 2004. [DOI: 10.1021/jp027543a] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Hyun S. Yoo
- Department of Chemistry, University of Virginia, McCormick Road, Charlottesville, Virginia 22904
| | - Merrick J. DeWitt
- Department of Chemistry, University of Virginia, McCormick Road, Charlottesville, Virginia 22904
| | - Brooks H. Pate
- Department of Chemistry, University of Virginia, McCormick Road, Charlottesville, Virginia 22904
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