1
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Fu J, Bian T, Yin J, Feng M, Xu Q, Wang Y, Sum TC. Organic and inorganic sublattice coupling in two-dimensional lead halide perovskites. Nat Commun 2024; 15:4562. [PMID: 38811539 PMCID: PMC11136976 DOI: 10.1038/s41467-024-48707-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Accepted: 05/10/2024] [Indexed: 05/31/2024] Open
Abstract
Two-dimensional layered organic-inorganic halide perovskites have successfully spread to diverse optoelectronic applications. Nevertheless, there remain gaps in our understanding of the interactions between organic and inorganic sublattices that form the foundation of their remarkable properties. Here, we examine these interactions using pump-probe spectroscopy and ab initio molecular dynamics simulations. Unlike off-resonant pumping, resonant excitation of the organic sublattice alters both the electronic and lattice degrees of freedom within the inorganic sublattice, indicating the existence of electronic coupling. Theoretical simulations verify that the reduced bandgap is likely due to the enhanced distortion index of the inorganic octahedra. Further evidence of the mechanical coupling between these two sublattices is revealed through the slow heat transfer process, where the resultant lattice tensile strain launches coherent longitudinal acoustic phonons. Our findings explicate the intimate electronic and mechanical couplings between the organic and inorganic sublattices, crucial for tailoring the optoelectronic properties of two-dimensional halide perovskites.
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Affiliation(s)
- Jianhui Fu
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore
| | - Tieyuan Bian
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, Hong Kong, 999077, PR China
| | - Jun Yin
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, Hong Kong, 999077, PR China.
| | - Minjun Feng
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore
| | - Qiang Xu
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore
| | - Yue Wang
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore
| | - Tze Chien Sum
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore.
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2
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Hanes AT, Grieco C, Lalisse RF, Hadad CM, Kohler B. Vibrational relaxation by methylated xanthines in solution: Insights from 2D IR spectroscopy and calculations. J Chem Phys 2023; 158:044302. [PMID: 36725522 DOI: 10.1063/5.0135412] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Two-dimensional infrared (2D IR) spectroscopy, infrared pump-infrared probe spectroscopy, and density functional theory calculations were used to study vibrational relaxation by ring and carbonyl stretching modes in a series of methylated xanthine derivatives in acetonitrile and deuterium oxide (heavy water). Isotropic signals from the excited symmetric and asymmetric carbonyl stretch modes decay biexponentially in both solvents. Coherent energy transfer between the symmetric and asymmetric carbonyl stretching modes gives rise to a quantum beat in the time-dependent anisotropy signals. The damping time of the coherent oscillation agrees with the fast decay component of the carbonyl bleach recovery signals, indicating that this time constant reflects intramolecular vibrational redistribution (IVR) to other solute modes. Despite their similar frequencies, the excited ring modes decay monoexponentially with a time constant that matches the slow decay component of the carbonyl modes. The slow decay times, which are faster in heavy water than in acetonitrile, approximately match the ones observed in previous UV pump-IR probe measurements on the same compounds. The slow component is assigned to intermolecular energy transfer to solvent bath modes from low-frequency solute modes, which are populated by IVR and are anharmonically coupled to the carbonyl and ring stretch modes. 2D IR measurements indicate that the carbonyl stretching modes are weakly coupled to the delocalized ring modes, resulting in slow exchange that cannot explain the common solvent-dependence. IVR is suggested to occur at different rates for the carbonyl vs ring modes due to differences in mode-specific couplings and not to differences in the density of accessible states.
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Affiliation(s)
- Alex T Hanes
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, USA
| | - Christopher Grieco
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, USA
| | - Remy F Lalisse
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, USA
| | - Christopher M Hadad
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, USA
| | - Bern Kohler
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, USA
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3
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Zhang RM, Xu X, Truhlar DG. Observing Intramolecular Vibrational Energy Redistribution via the Short-Time Fourier Transform. J Phys Chem A 2022; 126:3006-3014. [PMID: 35522826 DOI: 10.1021/acs.jpca.1c09905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Intramolecular vibrational energy relaxation (IVR) is important in many problems in chemical physics. Here, we apply the short-time Fourier transform method for analyzing IVR with classical dynamics. Calculating time-dependent Fourier transforms to perform such an analysis requires extending the usual Fourier transform method, and we do that here. The guiding concept behind the generalization is that if there is a shift of vibrational energy from one frequency range to another, we see a difference between the spectrum before the shift and the spectrum after the shift. We use time-window functions to transform the power spectrum of a trajectory into a time-dependent density spectrum of the average kinetic energy. The time-dependent average kinetic energy for each interval of the spectrum becomes an indicator to monitor the extent and nature of the energy transfer into and out of the corresponding modes. We illustrate this method for the H2O molecule. By analyzing cases with different initial conditions, we show that the short-time Fourier transform method can distinguish trends in IVR that depend on the initial distribution of energy and not just on the total energy.
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Affiliation(s)
- Rui Ming Zhang
- Center for Combustion Energy, Department of Energy and Power Engineering, and Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Tsinghua University, Beijing 100084, China.,Department of Chemistry, Chemical Theory Center, and Minnesota Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431, United States
| | - Xuefei Xu
- Center for Combustion Energy, Department of Energy and Power Engineering, and Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Tsinghua University, Beijing 100084, China
| | - Donald G Truhlar
- Department of Chemistry, Chemical Theory Center, and Minnesota Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431, United States
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4
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Djavani-Tabrizi I, Jockusch RA. Gas-Phase Fluorescence of Proflavine Reveals Two Close-Lying, Brightly Emitting States. J Phys Chem Lett 2022; 13:2187-2192. [PMID: 35230120 DOI: 10.1021/acs.jpclett.2c00201] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Surprising excitation-dependent, dual emission from a small organic model fluorophore is reported. Gas-phase fluorescence spectra of proflavine (a diaminoacridine) ions reveal two long-lived emitting states, with distinct bands separated by just 1700 cm-1. The relative intensities of these two bands depend on the excitation wavelength. Time-dependent density functional theory (TD-DFT) calculations support the existence of two close-lying singlet electronic states, with excitation into S2 predicted to be >1000-fold more likely than into S1. These data strongly suggest that internal conversion (IC) rates are suppressed relative to solvated proflavine, and that IC is competitive with intramolecular vibrational relaxation (IVR). This work offers an in-depth assessment of the gas-phase photophysics of a simple fluorophore that could open a new pathway to understanding dual emission in fluorophores.
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Affiliation(s)
| | - Rebecca A Jockusch
- Department of Chemistry, University of Toronto, Toronto, Ontario M5S3H6, Canada
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5
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Abstract
The Menshutkin reaction is a methyl transfer reaction relevant in fields ranging from biochemistry to chemical synthesis. In the present work, the energetics and solvent distributions for NH3+MeCl and Pyr+MeBr reactions were investigated in explicit solvent (water, methanol, acetonitrile, benzene, cyclohexane) by means of reactive molecular dynamics simulations. For polar solvents (water, methanol, and acetonitrile) and benzene, strong to moderate catalytic effects for both reactions were found, whereas apolar and bulky cyclohexane interacts weakly with the solute and does not show pronounced barrier reduction. The calculated barrier heights for the Pyr+MeBr reaction in acetonitrile and cyclohexane are 23.2 and 28.1 kcal/mol compared with experimentally measured barriers of 22.5 and 27.6 kcal/mol, respectively. The solvent distributions change considerably between reactant and TS but comparatively little between TS and product conformations of the solute. As the system approaches the transition state, correlated solvent motions occur which destabilize the solvent-solvent interactions. This is required for the system to surmount the barrier. Finally, it is found that the average solvent-solvent interaction energies in the reactant, TS, and product state geometries are correlated with changes in the solvent structure around the solute.
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Affiliation(s)
- Haydar Taylan Turan
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel, Switzerland
| | - Sebastian Brickel
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel, Switzerland
| | - Markus Meuwly
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel, Switzerland
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6
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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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7
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Infrared-pump electronic-probe of methylammonium lead iodide reveals electronically decoupled organic and inorganic sublattices. Nat Commun 2019; 10:482. [PMID: 30696817 PMCID: PMC6351559 DOI: 10.1038/s41467-019-08363-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Accepted: 12/28/2018] [Indexed: 11/09/2022] Open
Abstract
Organic-inorganic hybrid perovskites such as methylammonium lead iodide (CH3NH3PbI3) are game-changing semiconductors for solar cells and light-emitting devices owing to their defect tolerance and exceptionally long carrier lifetimes and diffusion lengths. Determining whether the dynamically disordered organic cations with large dipole moment benefit the optoelectronic properties of CH3NH3PbI3 has been an outstanding challenge. Herein, via transient absorption measurements employing an infrared pump pulse tuned to a methylammonium vibration, we observe slow, nanosecond-long thermal dissipation from the selectively excited organic mode to the inorganic sublattice. The resulting transient electronic signatures, during the period of thermal-nonequilibrium when the induced thermal motions are mostly concentrated on the organic sublattice, reveal that the induced atomic motions of the organic cations do not alter the absorption or the photoluminescence response of CH3NH3PbI3, beyond thermal effects. Our results suggest that the attractive optoelectronic properties of CH3NH3PbI3 mainly derive from the inorganic lead-halide framework.
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8
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Eckert PA, Kubarych KJ. Solvent Quality Controls Macromolecular Structural Dynamics of a Dendrimeric Hydrogenase Model. J Phys Chem B 2018; 122:12154-12163. [PMID: 30427195 DOI: 10.1021/acs.jpcb.8b07259] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
We report a spectroscopic investigation of the ultrafast dynamics of the second-generation poly(aryl ether) dendritic hydrogenase model using two-dimensional infrared (2D-IR) spectroscopy to probe the metal carbonyl vibrations of the dendrimer and a reference small molecule, [Fe(μ-S)(CO)3]2. We find that the structural dynamics of the dendrimer are reflected in a slow phase of the spectral diffusion, which is absent from [Fe(μ-S)(CO)3]2, and we relate the slow phase to the quality of the solvent for poly(aryl ether) dendrimers. We observe a solvent-dependent modulation of the initial phase of vibrational relaxation of the carbonyl groups, which we attribute to an inhibition of solvent assistance in the intramolecular vibrational redistribution process for the dendrimer. There is also a clear solvent dependence of the vibrational frequencies of both the dendrimer and [Fe(μ-S)(CO)3]2. Our data represent the first 2D-IR study of a dendritic complex and provide insight into the solvent dependence of molecular conformation in solution and the ultrafast dynamics of moderately sized, conformationally mobile compounds.
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Affiliation(s)
- Peter A Eckert
- Department of Chemistry , University of Michigan , 930 N. University Avenue , Ann Arbor , Michigan 49109 , United States
| | - Kevin J Kubarych
- Department of Chemistry , University of Michigan , 930 N. University Avenue , Ann Arbor , Michigan 49109 , United States
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9
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Kurouchi H, Singleton DA. Labelling and determination of the energy in reactive intermediates in solution enabled by energy-dependent reaction selectivity. Nat Chem 2018; 10:237-241. [PMID: 29359761 PMCID: PMC5785089 DOI: 10.1038/nchem.2907] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Accepted: 11/08/2017] [Indexed: 11/26/2022]
Abstract
Any long-lived chemical structure in solution is subject to statistical energy equilibration, so the history of any specific structure does not affect its subsequent reactions. This is not true for very short-lived intermediates, since energy equilibration takes time. Here, this idea is applied to achieve the energy labeling of a reactive intermediate. The selectivity of the ring-opening α-cleavage reaction of 1-methylcyclobutoxy radical is found here to vary broadly depending on how the radical was formed. Reactions that provide little excess energy to the intermediate lead to high selectivity in the subsequent cleavage (measured as a kinetic isotope effect) while reactions that provide more excess energy to the intermediate exhibit lower selectivity. Allowing for the expected excess energy allows the prediction of the observed product ratios, and in turn the product ratios can be used to obtain a read-out of the energy present in a intermediate.
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Affiliation(s)
- Hiroaki Kurouchi
- Department of Chemistry, Texas A&M University, College Station, Texas 77842, USA
| | - Daniel A Singleton
- Department of Chemistry, Texas A&M University, College Station, Texas 77842, USA
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10
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Nançoz C, Licari G, Beckwith JS, Soederberg M, Dereka B, Rosspeintner A, Yushchenko O, Letrun R, Richert S, Lang B, Vauthey E. Influence of the hydrogen-bond interactions on the excited-state dynamics of a push–pull azobenzene dye: the case of Methyl Orange. Phys Chem Chem Phys 2018; 20:7254-7264. [DOI: 10.1039/c7cp08390d] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
H-bonding with the solvent affects significantly the photoisomerisation of Methyl Orange.
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Affiliation(s)
- Christoph Nançoz
- Department of Physical Chemistry
- University of Geneva
- CH-1211 Geneva 4
- Switzerland
| | - Giuseppe Licari
- Department of Physical Chemistry
- University of Geneva
- CH-1211 Geneva 4
- Switzerland
| | - Joseph S. Beckwith
- Department of Physical Chemistry
- University of Geneva
- CH-1211 Geneva 4
- Switzerland
| | - Magnus Soederberg
- Department of Physical Chemistry
- University of Geneva
- CH-1211 Geneva 4
- Switzerland
| | - Bogdan Dereka
- Department of Physical Chemistry
- University of Geneva
- CH-1211 Geneva 4
- Switzerland
| | - Arnulf Rosspeintner
- Department of Physical Chemistry
- University of Geneva
- CH-1211 Geneva 4
- Switzerland
| | | | - Romain Letrun
- Department of Physical Chemistry
- University of Geneva
- CH-1211 Geneva 4
- Switzerland
| | - Sabine Richert
- Department of Physical Chemistry
- University of Geneva
- CH-1211 Geneva 4
- Switzerland
| | - Bernhard Lang
- Department of Physical Chemistry
- University of Geneva
- CH-1211 Geneva 4
- Switzerland
| | - Eric Vauthey
- Department of Physical Chemistry
- University of Geneva
- CH-1211 Geneva 4
- Switzerland
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11
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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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12
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Bailey JO, Singleton DA. Failure and Redemption of Statistical and Nonstatistical Rate Theories in the Hydroboration of Alkenes. J Am Chem Soc 2017; 139:15710-15723. [PMID: 29029560 PMCID: PMC5831723 DOI: 10.1021/jacs.7b07175] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Our previous work found that canonical forms of transition state theory incorrectly predict the regioselectivity of the hydroboration of propene with BH3 in solution. In response, it has been suggested that alternative statistical and nonstatistical rate theories can adequately account for the selectivity. This paper uses a combination of experimental and theoretical studies to critically evaluate the ability of these rate theories, as well as dynamic trajectories and newly developed localized statistical models, to predict quantitative selectivities and qualitative trends in hydroborations on a broader scale. The hydroboration of a series of terminally substituted alkenes with BH3 was examined experimentally, and a classically unexpected trend is that the selectivity increases as the alkyl chain is lengthened far from the reactive centers. Conventional and variational transition state theories can predict neither the selectivities nor the trends. The canonical competitive nonstatistical model makes somewhat better predictions for some alkenes but fails to predict trends, and it performs poorly with an alkene chosen to test a specific prediction of the model. Added nonstatistical corrections to this model make the predictions worse. Parametrized Rice-Ramsperger-Kassel-Marcus (RRKM)-master equation calculations correctly predict the direction of the trend in selectivity versus alkene size but overpredict its magnitude, and the selectivity with large alkenes remains unpredictable with any parametrization. Trajectory studies in explicit solvent can predict selectivities without parametrization but are impractical for predicting small changes in selectivity. From a lifetime and energy analysis of the trajectories, "localized RRKM-ME" and "competitive localized noncanonical" rate models are suggested as steps toward a general model. These provide the best predictions of the experimental observations and insight into the selectivities.
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Affiliation(s)
- Johnathan O. Bailey
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842, United States
| | - Daniel A. Singleton
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842, United States
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13
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Kumpulainen T, Lang B, Rosspeintner A, Vauthey E. Ultrafast Elementary Photochemical Processes of Organic Molecules in Liquid Solution. Chem Rev 2016; 117:10826-10939. [DOI: 10.1021/acs.chemrev.6b00491] [Citation(s) in RCA: 249] [Impact Index Per Article: 31.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Tatu Kumpulainen
- Department of Physical Chemistry,
Sciences II, University of Geneva, 30 Quai Ernest Ansermet, CH-1211 Geneva 4, Switzerland
| | - Bernhard Lang
- Department of Physical Chemistry,
Sciences II, University of Geneva, 30 Quai Ernest Ansermet, CH-1211 Geneva 4, Switzerland
| | - Arnulf Rosspeintner
- Department of Physical Chemistry,
Sciences II, University of Geneva, 30 Quai Ernest Ansermet, CH-1211 Geneva 4, Switzerland
| | - Eric Vauthey
- Department of Physical Chemistry,
Sciences II, University of Geneva, 30 Quai Ernest Ansermet, CH-1211 Geneva 4, Switzerland
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14
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Vibrational relaxation of NO3−(aq). Chem Phys 2014. [DOI: 10.1016/j.chemphys.2014.03.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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15
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Koch M, Rosspeintner A, Adamczyk K, Lang B, Dreyer J, Nibbering ETJ, Vauthey E. Real-Time Observation of the Formation of Excited Radical Ions in Bimolecular Photoinduced Charge Separation: Absence of the Marcus Inverted Region Explained. J Am Chem Soc 2013; 135:9843-8. [DOI: 10.1021/ja403481v] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Marius Koch
- Department of Physical Chemistry, University of Geneva, 30 Quai Ernest-Ansermet, CH-1211
Geneva 4, Switzerland
| | - Arnulf Rosspeintner
- Department of Physical Chemistry, University of Geneva, 30 Quai Ernest-Ansermet, CH-1211
Geneva 4, Switzerland
| | - Katrin Adamczyk
- Max Born Institut für Nichtlineare Optik und Kurzzeitspektroskopie, Max-Born-Strasse 2A, 12489 Berlin, Germany
| | - Bernhard Lang
- Department of Physical Chemistry, University of Geneva, 30 Quai Ernest-Ansermet, CH-1211
Geneva 4, Switzerland
| | - Jens Dreyer
- Max Born Institut für Nichtlineare Optik und Kurzzeitspektroskopie, Max-Born-Strasse 2A, 12489 Berlin, Germany
| | - Erik T. J. Nibbering
- Max Born Institut für Nichtlineare Optik und Kurzzeitspektroskopie, Max-Born-Strasse 2A, 12489 Berlin, Germany
| | - Eric Vauthey
- Department of Physical Chemistry, University of Geneva, 30 Quai Ernest-Ansermet, CH-1211
Geneva 4, Switzerland
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16
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Zhang Y, Oliver TAA, Ashfold MNR, Bradforth SE. Contrasting the excited state reaction pathways of phenol and para-methylthiophenol in the gas and liquid phases. Faraday Discuss 2013; 157:141-63; discussion 243-84. [PMID: 23230767 DOI: 10.1039/c2fd20043k] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
To explore how the solvent influences primary aspects of bond breaking, the gas and solution phase photochemistries of phenol and ofpara-methylthiophenol are directly compared using, respectively, H (Rydberg) atom photofragment translation spectroscopy and femtosecond transient absorption spectroscopy. Approaches are demonstrated that allow explicit comparisons of the nascent product energy disposals and dissociation mechanisms in the two phases. It is found, at least for the case of the weakly perturbing cyclohexane environment, that most aspects of the primary reaction dynamics of the isolated molecule are reproduced in solution. Specifically, in the gas phase, both molecules can undergo fast X-H (X = O, S) bond dissociation upon excitation with short wavelengths (193 < lambda(pump) < 216 nm), following population of the dissociative S2 (1 1(pi sigma*)) state. Product electronic branching, vibrational and translational energy disposals are determined. Photolysis of phenol and para-methylthiophenol in solution at 200 nm results in formation of vibrationally excited radicals on a timescale shorter than 200 fs. Excitation of para-methylthiophenol at 267 nm reaches close to the S1 (1 1(pipi*))/S2 (11(pi sigma*)) conical intersection (CI): ultrafast dissociation is observed in both the isolated and solution systems-again indicating direct dissociation on the S2 potential energy surface. Comparing results for this precursor at different excitation energies, the extent of geminate recombination and the derived H-atom ejection lengths in the condensed phase photolyses are in qualitative agreement with the translational energy release measured in the gas phase studies. Conversely, excitation of phenol at 267 nm prepares the system in its S1 state at an energy well below its S1/S2 CI; the slow O-H bond fission inferred in the gas phase experiments is observed directly in the time-resolved studies in cyclohexane solution via the appearance of phenoxyl radical absorption after -1 ns, with only S1 excited state absorption discernible at earlier delay times. The slow O-H bond fission in solution provides additional evidence for a tunnelling dissociation mechanism, where the H atom tunnels beneath the lower diabats of the S2/S1 CI. Finally, the photodissociation of phenol clusters in solution is considered, where evidence is presented that the O-H dissociation coordinate is impeded in H-bonded dimers.
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Affiliation(s)
- Yuyuan Zhang
- Department of Chemistry, University of Southern California, Los Angeles, CA 90089, USA
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17
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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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18
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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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19
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Dunkelberger AD, Kieda RD, Shin JY, Rossi Paccani R, Fusi S, Olivucci M, Fleming Crim F. Photoisomerization and Relaxation Dynamics of a Structurally Modified Biomimetic Photoswitch. J Phys Chem A 2012; 116:3527-33. [DOI: 10.1021/jp300153a] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- Adam D. Dunkelberger
- Department of Chemistry, University of Wisconsin—Madison, Madison, Wisconsin
53706, United States
| | - Ryan D. Kieda
- Department of Chemistry, University of Wisconsin—Madison, Madison, Wisconsin
53706, United States
| | - Jae Yoon Shin
- Department of Chemistry, University of Wisconsin—Madison, Madison, Wisconsin
53706, United States
| | | | - Stefania Fusi
- Department
of Chemistry, Università di Siena, Siena I-53100, Italy
| | - Massimo Olivucci
- Department
of Chemistry, Università di Siena, Siena I-53100, Italy
- Department
of Chemistry, Bowling Green State University, Bowling Green, Ohio
43403, United States
| | - F. Fleming Crim
- Department of Chemistry, University of Wisconsin—Madison, Madison, Wisconsin
53706, United States
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20
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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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21
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King JT, Anna JM, Kubarych KJ. Solvent-hindered intramolecular vibrational redistribution. Phys Chem Chem Phys 2011; 13:5579-83. [PMID: 21359345 DOI: 10.1039/c0cp02138e] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ultrafast two-dimensional infrared spectroscopy and molecular dynamics simulations of Mn(2)(CO)(10) in a series of linear alcohols reveal that the rate of intramolecular vibrational redistribution among the terminal carbonyl stretches is dictated by the average number of hydrogen bonds formed between the solute and solvent. The presence of hydrogen bonds was found to hinder vibrational redistribution between eigenstates, while leaving the overall T(1) relaxation rate unchanged.
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Affiliation(s)
- John T King
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA
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22
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Oliver TAA, Zhang Y, Ashfold MNR, Bradforth SE. Linking photochemistry in the gas and solution phase: S–H bond fission in p-methylthiophenol following UV photoexcitation. Faraday Discuss 2011; 150:439-58; discussion 505-32. [DOI: 10.1039/c0fd00031k] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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23
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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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24
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Glowacki DR, Liang CH, Marsden SP, Harvey JN, Pilling MJ. Alkene Hydroboration: Hot Intermediates That React While They Are Cooling. J Am Chem Soc 2010; 132:13621-3. [DOI: 10.1021/ja105100f] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- David R. Glowacki
- Centre for Computational Chemistry, University of Bristol, Bristol BS8 1TS, United Kingdom, and School of Chemistry, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - C. H. Liang
- Centre for Computational Chemistry, University of Bristol, Bristol BS8 1TS, United Kingdom, and School of Chemistry, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Stephen P. Marsden
- Centre for Computational Chemistry, University of Bristol, Bristol BS8 1TS, United Kingdom, and School of Chemistry, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Jeremy N. Harvey
- Centre for Computational Chemistry, University of Bristol, Bristol BS8 1TS, United Kingdom, and School of Chemistry, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Michael J. Pilling
- Centre for Computational Chemistry, University of Bristol, Bristol BS8 1TS, United Kingdom, and School of Chemistry, University of Leeds, Leeds LS2 9JT, United Kingdom
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25
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Oyola Y, Singleton DA. Dynamics and the failure of transition state theory in alkene hydroboration. J Am Chem Soc 2010; 131:3130-1. [PMID: 19215077 DOI: 10.1021/ja807666d] [Citation(s) in RCA: 124] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Transition state theory fails to accurately predict the selectivity in an example where it is ubiquitously invoked, hydroboration. The hydroboration of terminal alkenes with BH(3) is moderately regioselective, affording an 88:12-90:10 ratio of anti-Markovnikov/Markovnikov adducts. High-level ab initio calculations predict too large of an energy difference between anti-Markovnikov and Markovnikov transition structures to account for the observed product ratio, and consideration of calculational error, solvent, tunneling, and entropy effects does not resolve the discrepancy. Trajectory studies, however, predict well the experimental selectivity. The decreased selectivity versus transition state theory arises from the excess energy generated as the BH(3) interacts with the alkene, and the observed selectivity is proposed to result from a combination of low selectivity in direct trajectories, moderate RRKM selectivity, and high selectivity after thermal equilibration.
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Affiliation(s)
- Yatsandra Oyola
- Department of Chemistry, Texas A&M University, PO Box 30012, College Station, Texas 77842, USA
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26
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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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27
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Carrier SL, Preston TJ, Dutta M, Crowther AC, Crim FF. Ultrafast Observation of Isomerization and Complexation in the Photolysis of Bromoform in Solution. J Phys Chem A 2009; 114:1548-55. [DOI: 10.1021/jp908725t] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Stacey L. Carrier
- Department of Chemistry University of Wisconsin—Madison, Madison, Wisconsin 53706
| | - Thomas J. Preston
- Department of Chemistry University of Wisconsin—Madison, Madison, Wisconsin 53706
| | - Maitreya Dutta
- Department of Chemistry University of Wisconsin—Madison, Madison, Wisconsin 53706
| | - Andrew C. Crowther
- Department of Chemistry University of Wisconsin—Madison, Madison, Wisconsin 53706
| | - F. Fleming Crim
- Department of Chemistry University of Wisconsin—Madison, Madison, Wisconsin 53706
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28
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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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29
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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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30
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Thomas JB, Waas JR, Harmata M, Singleton DA. Control elements in dynamically determined selectivity on a bifurcating surface. J Am Chem Soc 2008; 130:14544-55. [PMID: 18847260 DOI: 10.1021/ja802577v] [Citation(s) in RCA: 125] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The mechanism and the nature of the dynamically determined product selectivity in Diels-Alder cycloadditions of 3-methoxycarbonylcyclopentadienone (2) with 1,3-dienes was studied by a combination of product studies, experimental kinetic isotope effects, standard theoretical calculations, and quasiclassical trajectory calculations. The low-energy transition structures in these reactions are structurally balanced between [4pi(diene) + 2pi(dienone)] and the [2pi(diene) + 4pi(dienone)] modes of cycloaddition. The accuracy of these structures and their bispericyclic nature is supported by the experimental isotope effects. Trajectories passing through these transition structures can lead to both [4pi(diene) + 2pi(dienone)] and [2pi(diene) + 4pi(dienone)] cycloadducts, and the mixture of products obtained varies with the structure of the diene. The factors affecting this selectivity are analyzed. The geometry of the transition structure is a useful predictor of the major product, but the selectivity is also guided by the shape of the energy surface as trajectories approach the products and by how trajectories cross the transition state ridge.
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Affiliation(s)
- Jacqueline B Thomas
- Department of Chemistry, Texas A&M University, PO Box 30012, College Station, Texas 77842, USA
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31
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Crim FF. Chemical dynamics of vibrationally excited molecules: Controlling reactions in gases and on surfaces. Proc Natl Acad Sci U S A 2008; 105:12654-61. [PMID: 18765816 PMCID: PMC2529117 DOI: 10.1073/pnas.0803010105] [Citation(s) in RCA: 134] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2008] [Indexed: 11/18/2022] Open
Abstract
Experimental studies of the chemical reaction dynamics of vibrationally excited molecules reveal the ability of different vibrations to control the course of a reaction. This Perspective describes those studies for the prototypical reaction of vibrationally excited methane and its isotopologues in gases and on surfaces and looks to the prospects of similar studies in liquids. The influences of vibrational excitation on the C-H bond cleavage in a single collision reaction with Cl and in dissociative adsorption on a Ni surface bear some striking similarities. Both reactions are bond-selective processes in which the initial preparation of a molecular eigenstate containing a large component of C-H stretching results in preferential cleavage of that bond. It is possible to cleave either the C-H bond or C-D bond in the reaction of Cl with CH3D, CH2D2, or CHD3 and, similarly, to use initial excitation of the C-H stretch to promote dissociation of CHD3 to CD3 and H on a Ni surface. Different vibrational modes, such as the symmetric and antisymmetric stretches in CH3D or CH4, lead to very different reactivities, and molecules with the symmetric stretching vibration excited can be as much as 10 times more reactive than ones with the antisymmetric stretch excited. The origin of this behavior lies in the change in the vibrational motion induced by the interaction with the atomic reaction partner or the surface.
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Affiliation(s)
- F Fleming Crim
- Department of Chemistry, University of Wisconsin, Madison, WI 53706, USA.
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32
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Conformational isomerization kinetics of pent-1-en-4-yne with 3,330 cm-1 of internal energy measured by dynamic rotational spectroscopy. Proc Natl Acad Sci U S A 2008; 105:12696-700. [PMID: 18678910 DOI: 10.1073/pnas.0800520105] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We demonstrate the application of molecular rotational spectroscopy to measure the conformation isomerization rate of vibrationally excited pent-1-en-4-yne (pentenyne). The rotational spectra of single quantum states of pentenyne are acquired by using a combination of IR-Fourier transform microwave double-resonance spectroscopy and high-resolution, single-photon IR spectroscopy. The quantum states probed in these experiments have energy eigenvalues of approximately 3,330 cm(-1) and lie above the barrier to conformational isomerization. At this energy, the presence of intramolecular vibrational energy redistribution (IVR) is indicated through the extensive local perturbations found in the high-resolution rotation-vibration spectrum of the acetylenic C-H stretch normal-mode fundamental. The fact that the IVR process produces isomerization is deduced through a qualitatively different appearance of the excited-state rotational spectra compared with the pure rotational spectra of pentenyne. The rotational spectra of the vibrationally excited molecular eigenstates display coalescence between the characteristic rotational frequencies of the stable cis and skew conformations of the molecule. This coalescence is observed for quantum states prepared from laser excitation originating in the ground vibrational state of either of the two stable conformers. Experimental isomerization rates are extracted by using a three-state Bloch model of the dynamic rotational spectra that includes the effects of chemical exchange between the stable conformations. The time scale for the conformational isomerization rate of pentenyne at total energy of 3,330 cm(-1) is approximately 25 ps and is 50 times slower than the microcanonical isomerization rate predicted by the statistical Rice-Ramsperger-Kassel-Marcus theory.
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33
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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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34
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Dian BC, Brown GG, Douglass KO, Pate BH. Measuring picosecond isomerization kinetics via broadband microwave spectroscopy. Science 2008; 320:924-8. [PMID: 18487191 DOI: 10.1126/science.1155736] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The rotational spectrum of a highly excited molecule is qualitatively different from its pure rotational spectrum and contains information about the intramolecular dynamics. We have developed a broadband Fourier transform microwave spectrometer that uses chirped-pulse excitation to measure a rotational spectrum in the 7.5- to 18.5-gigahertz range in a single shot and thereby reduces acquisition time sufficiently to couple molecular rotational spectroscopy with tunable laser excitation. After vibrationally exciting a single molecular conformation of cyclopropane carboxaldehyde above the barrier to C-C single-bond isomerization, we applied line-shape analysis of the dynamic rotational spectrum to reveal a product yield and picosecond reaction rate that were significantly different from statistical predictions. The technique should be widely applicable to dynamical studies of radical intermediates, molecular complexes, and conformationally flexible molecules with biological interest.
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Affiliation(s)
- Brian C Dian
- Department of Chemistry, University of Virginia, McCormick Road, Charlottesville, VA 22904-4319, USA
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35
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Horká V, Quack M, Willeke M. Analysis of the CH-chromophore spectra and dynamics in dideutero-methyliodide CHD2I1. Mol Phys 2008. [DOI: 10.1080/00268970802275611] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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36
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Ito F. Infrared spectra of (HCOOH)2 and (DCOOH)2 in rare gas matrices: A comparative study with gas phase spectra. J Chem Phys 2008; 128:114310. [DOI: 10.1063/1.2841078] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
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37
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Pigliucci A, Duvanel G, Daku LML, Vauthey E. Investigation of the Influence of Solute−Solvent Interactions on the Vibrational Energy Relaxation Dynamics of Large Molecules in Liquids. J Phys Chem A 2007; 111:6135-45. [PMID: 17591756 DOI: 10.1021/jp069010y] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The influence of solute-solvent interactions on the vibrational energy relaxation dynamics of perylene and substituted perylenes in the first singlet excited-state upon excitation with moderate (<0.4 eV) excess energy has been investigated by monitoring the early narrowing of their fluorescence spectrum. This narrowing was found to occur on timescales ranging from a few hundreds of femtoseconds to a few picoseconds. Other processes, such as a partial decay of the fluorescence anisotropy and the damping of a low-frequency oscillation due to the propagation of a vibrational wavepacket, were found to take place on a very similar time scale. No significant relationship between the strength of nonspecific solute-solvent interactions and the vibrational energy relaxation dynamics of the solutes could be evidenced. On the other hand, in alcohols the spectral narrowing is faster with a solute having H-bonding sites, indicating that this specific interaction tends to favor vibrational energy relaxation. No relationship between the dynamics of spectral narrowing and macroscopic solvent properties, such as the thermal diffusivity, could be found. On the other hand, a correlation between this narrowing dynamics and the number of low-frequency modes of the solvent molecules was evidenced. All these observations cannot be discussed with a model where vibrational energy relaxation occurs via two consecutive and dynamically well-separated steps, namely ultrafast intramolecular vibrational redistribution followed by slower vibrational cooling. On the contrary, the results indicate that both intra- and intermolecular vibrational energy redistribution processes are closely entangled and occur, at least partially, on similar timescales.
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Affiliation(s)
- Anatolio Pigliucci
- Department of Physical Chemistry, University of Geneva, 30 quai Ernest-Ansermet, CH-1211 Genève 4, Switzerland
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38
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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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39
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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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40
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Ramesh SG, Sibert EL. Time scales and pathways of vibrational energy relaxation in liquid CHBr3 and CDBr3. J Chem Phys 2006; 125:244512. [PMID: 17199360 DOI: 10.1063/1.2403875] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Molecular dynamics simulations are used in conjunction with Landau-Teller, fluctuating Landau-Teller, and time-dependent perturbation theories to investigate energy flow out of various vibrational states of liquid CHBr3 and CDBr3. The CH stretch overtone is found to relax with a time scale of about 1 ps compared to the 50 ps rate for the fundamental. The relaxation pathways and rates for the CD stretch decay in CDBr3 are computed in order to understand the changes arising from deuteration. While the computed relaxation rate agrees well with experiments, the pathway is found to be more complex than anticipated. In addition to the above channels for CH(D) stretch relaxation that involve only the hindered translations and rotations of the solvent, routes involving off-resonant and resonant excitations of solvent vibrational modes are also examined. Finally, the decay of energy from low frequency states to near-lying solute states and solvent vibrations are studied.
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Affiliation(s)
- Sai G Ramesh
- Theoretical Chemistry Institute, Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
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41
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Picosecond time-resolved study on the intramolecular vibrational energy redistribution of NH stretching vibration of jet-cooled aniline and its isotopomer. Chem Phys Lett 2006. [DOI: 10.1016/j.cplett.2006.10.118] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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42
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Lenchenkov V, She C, Lian T. Vibrational Relaxation of CN Stretch of Pseudo-Halide Anions (OCN-, SCN-, and SeCN-) in Polar Solvents. J Phys Chem B 2006; 110:19990-7. [PMID: 17020387 DOI: 10.1021/jp062326l] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The vibrational relaxation dynamics of pseudo-halide anions XCN- (X = O, S, Se) in polar solvents were studied to understand the effect of charge on solute-to-solvent intermolecular energy transfer (IET) and solvent assisted intramolecular vibrational relaxation (IVR) pathways. The T1 relaxation times of the CN stretch in these anions were measured by IR pump/IR probe spectroscopy, in which the 0-1 transition was excited, and the 0-1 and 1-2 transitions were monitored to follow the recovery of the ground state and decay of the excited state. For these anions in five solvents, H2O, D2O, CH3OH, CH3CN, and (CH3)2SO, relaxation rates followed the trend of OCN- > SCN- > SeCN-. For these anions and isotopes of SCN-, the relaxation rate was a factor of a few (2.5-10) higher in H2O than in D2O. To further probe the solvent isotope effect, the relaxation rates of S12C14N-, S13C14N-, and S12C15N- in deuterated methanols (CH3OH, CH3OD, CH3OH, CD3OD) were compared. Relaxation rate was found to be affected by the change of solvent vibrational band at the CN- stretching mode (CD3 symmetric stretch) and lower frequency regions, suggesting the presence of both direct IET and solvent assisted IVR relaxation pathways. The possible relaxation pathways and mechanisms for the observed trends in solute and solvent dependence were discussed.
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Affiliation(s)
- Victor Lenchenkov
- Department of Chemistry, Emory University, Atlanta, Georgia 30322, USA
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43
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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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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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Kiba T, Sato SI, Akimoto S, Kasajima T, Yamazaki I. Solvent-assisted intramolecular vibrational energy redistribution of S1 perylene in ketone solvents. J Photochem Photobiol A Chem 2006. [DOI: 10.1016/j.jphotochem.2005.09.032] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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47
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Lee S, Engel M, Gruebele M. The state space model of vibrational energy flow: An experimental test using SEP spectra of jet-cooled thiophosgene. Chem Phys Lett 2006. [DOI: 10.1016/j.cplett.2005.12.064] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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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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Mazyar OA, Hase WL. Dynamics and Kinetics of Heat Transfer at the Interface of Model Diamond {111} Nanosurfaces. J Phys Chem A 2005; 110:526-36. [PMID: 16405325 DOI: 10.1021/jp0521961] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A molecular dynamics simulation was performed to study the effect of an applied force on heat transfer at the interface of model diamond [111] nanosurfaces. The force was applied to a small, hot nanosurface at 800, 1000, or 1200 K brought into contact with a larger, colder nanosurface at 300 K. The relaxation of the initial nonequilibrium interfacial force occurs on a subpicosecond time scale, much shorter than that required for heat transfer. Heat transfer occurs with exponential kinetics and a rate constant that increases linearly with the interfacial force according to 7 x 10(-4) ps(-1)/nN. This rate constant only increases by at most 10% as the temperature of the hot surface is increased from 800 to 1200 K. Replacing the interfacial H-atoms on both surfaces by D atoms also has a very small effect on the heat transfer. However, if one nanosurface has H atoms on its interface and the other nanosurface's interface has D atoms, then there is a marked 25% decrease in the rate constant for heat transfer. Increasing the size of the hot surface, and, thus, the interfacial contact area, increases the rate of heat transfer but not the rate constant. For the same interfacial force, different anharmonic models for the nanosurfaces' potential energy function give the same heat transfer rate constant. The possibility of quantum effects for heat transfer across the diamond interface is considered.
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Affiliation(s)
- Oleg A Mazyar
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409-1061, USA
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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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