51
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Zhu J, Paparelli L, Hospes M, Arents J, Kennis JTM, van Stokkum IHM, Hellingwerf KJ, Groot ML. Photoionization and Electron Radical Recombination Dynamics in Photoactive Yellow Protein Investigated by Ultrafast Spectroscopy in the Visible and Near-Infrared Spectral Region. J Phys Chem B 2013; 117:11042-8. [DOI: 10.1021/jp311906f] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Jingyi Zhu
- Department
of Physics and Astronomy,
Faculty of Sciences, VU University, De
Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Laura Paparelli
- Department
of Physics and Astronomy,
Faculty of Sciences, VU University, De
Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Marijke Hospes
- Laboratory for Microbiology,
Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The
Netherlands
| | - Jos Arents
- Laboratory for Microbiology,
Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The
Netherlands
| | - John T. M. Kennis
- Department
of Physics and Astronomy,
Faculty of Sciences, VU University, De
Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Ivo H. M. van Stokkum
- Department
of Physics and Astronomy,
Faculty of Sciences, VU University, De
Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Klaas J. Hellingwerf
- Laboratory for Microbiology,
Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The
Netherlands
| | - Marie Louise Groot
- Department
of Physics and Astronomy,
Faculty of Sciences, VU University, De
Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
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52
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Harris SJ, Murdock D, Zhang Y, Oliver TAA, Grubb MP, Orr-Ewing AJ, Greetham GM, Clark IP, Towrie M, Bradforth SE, Ashfold MNR. Comparing molecular photofragmentation dynamics in the gas and liquid phases. Phys Chem Chem Phys 2013; 15:6567-82. [PMID: 23552482 DOI: 10.1039/c3cp50756d] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This article explores the extent to which insights gleaned from detailed studies of molecular photodissociations in the gas phase (i.e. under isolated molecule conditions) can inform our understanding of the corresponding photofragmentation processes in solution. Systems selected for comparison include a thiophenol (p-methylthiophenol), a thioanisole (p-methylthioanisole) and phenol, in vacuum and in cyclohexane solution. UV excitation in the gas phase results in RX-Y (X = O, S; Y = H, CH3) bond fission in all cases, but over timescales that vary by ~4 orders of magnitude - all of which behaviours can be rationalised on the basis of the relevant bound and dissociative excited state potential energy surfaces (PESs) accessed by UV photoexcitation, and of the conical intersections that facilitate radiationless transfer between these PESs. Time-resolved UV pump-broadband UV/visible probe and/or UV pump-broadband IR probe studies of the corresponding systems in cyclohexane solution reveal additional processes that are unique to the condensed phase. Thus, for example, the data clearly reveal evidence of (i) vibrational relaxation of the photoexcited molecules prior to their dissociation and of the radical fragments formed upon X-Y bond fission, and (ii) geminate recombination of the RX and Y products (leading to reformation of the ground state parent and/or isomeric adducts). Nonetheless, the data also show that, in each case, the characteristics (and the timescale) of the initial bond fission process that occurs under isolated molecule conditions are barely changed by the presence of a weakly interacting solvent like cyclohexane. These condensed phase studies are then extended to an ether analogue of phenol (allyl phenyl ether), wherein UV photo-induced RO-allyl bond fission constitutes the first step of a photo-Claisen rearrangement.
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Affiliation(s)
- Stephanie J Harris
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK
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53
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Sailer CF, Thallmair S, Fingerhut BP, Nolte C, Ammer J, Mayr H, Pugliesi I, de Vivie-Riedle R, Riedle E. A Comprehensive Microscopic Picture of the Benzhydryl Radical and Cation Photogeneration and Interconversion through Electron Transfer. Chemphyschem 2013; 14:1423-37. [DOI: 10.1002/cphc.201201057] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Indexed: 11/09/2022]
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54
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Zhu J, Paparelli L, Hospes M, Arents J, Hellingwerf K, Kennis JT, van Stokkum IH, Louise Groot M. Ultrafast geminate electron-radical recombination dynamics in photoactive yellow protein. EPJ WEB OF CONFERENCES 2013. [DOI: 10.1051/epjconf/20134107010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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55
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Suzuki T. Visualization of chemical reaction dynamics: toward understanding complex polyatomic reactions. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2013; 89:1-15. [PMID: 23318678 PMCID: PMC3610866 DOI: 10.2183/pjab.89.1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2012] [Accepted: 10/12/2012] [Indexed: 06/01/2023]
Abstract
Polyatomic molecules have several electronic states that have similar energies. Consequently, their chemical dynamics often involve nonadiabatic transitions between multiple potential energy surfaces. Elucidating the complex reactions of polyatomic molecules is one of the most important tasks of theoretical and experimental studies of chemical dynamics. This paper describes our recent experimental studies of the multidimensional multisurface dynamics of polyatomic molecules based on two-dimensional ion/electron imaging. It also discusses ultrafast photoelectron spectroscopy of liquids for elucidating nonadiabatic electronic dynamics in aqueous solutions. (Communicated by Hiroo INOKUCHI, M.J.A.)
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Affiliation(s)
- Toshinori Suzuki
- Department of Chemistry, Graduate School of Science, Kyoto University.
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56
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Neogi SG, Chaudhury P. Structure and spectroscopic aspects of water-halide ion clusters: A study based on a conjunction of stochastic and quantum chemical methods. J Comput Chem 2012; 34:471-91. [DOI: 10.1002/jcc.23156] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2012] [Revised: 09/01/2012] [Accepted: 09/07/2012] [Indexed: 01/17/2023]
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57
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Turi L, Rossky PJ. Theoretical studies of spectroscopy and dynamics of hydrated electrons. Chem Rev 2012; 112:5641-74. [PMID: 22954423 DOI: 10.1021/cr300144z] [Citation(s) in RCA: 129] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- László Turi
- Department of Physical Chemistry, Eötvös Loránd University, Budapest, Hungary.
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58
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Chiou MF, Sheu WS. Exploring water binding motifs to an excess electron via X2(-)(H2O) [X = O, F]. J Phys Chem A 2012; 116:7694-702. [PMID: 22762788 DOI: 10.1021/jp3030232] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
X(2)(-)(H(2)O) [X = O, F] is utilized to explore water binding motifs to an excess electron via ab initio calculations at the MP4(SDQ)/aug-cc-pVDZ + diffs(2s2p,2s2p) level of theory. X(2)(-)(H(2)O) can be regarded as a water molecule that binds to an excess electron, the distribution of which is gauged by X(2). By varying the interatomic distance of X(2), r(X1-X2), the distribution of the excess electron is altered, and the water binding motifs to the excess electron is then examined. Depending on r(X1-X2), both binding motifs of C(s) and C(2v) forms are found with a critical distance of ∼1.37 Å and ∼1.71 Å for O(2)(-)(H(2)O) and F(2)(-)(H(2)O), respectively. The energetic and geometrical features of O(2)(-)(H(2)O) and F(2)(-)(H(2)O) are compared. In addition, various electronic properties of X(2)(-)(H(2)O) are examined. For both O(2)(-)(H(2)O) and F(2)(-)(H(2)O), the C(s) binding motif appears to prevail at a compact distribution of the excess electron. However, when the electron is diffuse, characterized by the radius of gyration in the direction of the X(2) bond axis with a threshold of ∼0.84 Å, the C(2v) binding motif is formed.
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Affiliation(s)
- Mong-Feng Chiou
- Department of Chemistry, Fu-Jen Catholic University, Xinzhuang, New Taipei City 24205, Taiwan, Republic of China
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59
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Molins i Domenech F, FitzPatrick B, Healy AT, Blank DA. Photodetachment and electron reactivity in 1-methyl-1-butyl-pyrrolidinium bis(trifluoromethylsulfonyl)amide. J Chem Phys 2012; 137:034512. [DOI: 10.1063/1.4736569] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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60
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Doan SC, Schwartz BJ. Ultrafast Studies of Excess Electrons in Liquid Acetonitrile: Revisiting the Solvated Electron/Solvent Dimer Anion Equilibrium. J Phys Chem B 2012; 117:4216-21. [DOI: 10.1021/jp303591h] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Stephanie C. Doan
- Department of Chemistry
and Biochemistry, University of California, Los Angeles, Los Angeles,
California 90095, United States
| | - Benjamin J. Schwartz
- Department of Chemistry
and Biochemistry, University of California, Los Angeles, Los Angeles,
California 90095, United States
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61
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Horio T, Shen H, Adachi S, Suzuki T. Photoelectron spectra of solvated electrons in bulk water, methanol, and ethanol. Chem Phys Lett 2012. [DOI: 10.1016/j.cplett.2012.03.051] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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62
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Suzuki T. Time-resolved photoelectron spectroscopy of non-adiabatic electronic dynamics in gas and liquid phases. INT REV PHYS CHEM 2012. [DOI: 10.1080/0144235x.2012.699346] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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63
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Abel B, Buck U, Sobolewski AL, Domcke W. On the nature and signatures of the solvated electron in water. Phys Chem Chem Phys 2012; 14:22-34. [DOI: 10.1039/c1cp21803d] [Citation(s) in RCA: 123] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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64
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Pham VT, Penfold TJ, van der Veen RM, Lima F, El Nahhas A, Johnson SL, Beaud P, Abela R, Bressler C, Tavernelli I, Milne CJ, Chergui M. Probing the Transition from Hydrophilic to Hydrophobic Solvation with Atomic Scale Resolution. J Am Chem Soc 2011; 133:12740-8. [DOI: 10.1021/ja203882y] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Van-Thai Pham
- Ecole Polytechnique Fédérale de Lausanne, Laboratoire de Spectroscopie Ultrarapide, ISIC-FSB, Station 6, CH-1015 Lausanne, Switzerland
| | - Thomas J. Penfold
- Ecole Polytechnique Fédérale de Lausanne, Laboratoire de Spectroscopie Ultrarapide, ISIC-FSB, Station 6, CH-1015 Lausanne, Switzerland
- Swiss Light Source, Paul-Scherrer-Institut, CH-5232 PSI-Villigen, Switzerland
- Ecole Polytechnique Fédérale de Lausanne, Laboratoire de Chimie Et Biochimie Computationnelles, ISIC-FSB, CH-1015 Lausanne, Switzerland
| | - Renske M. van der Veen
- Ecole Polytechnique Fédérale de Lausanne, Laboratoire de Spectroscopie Ultrarapide, ISIC-FSB, Station 6, CH-1015 Lausanne, Switzerland
- Swiss Light Source, Paul-Scherrer-Institut, CH-5232 PSI-Villigen, Switzerland
| | - Frederico Lima
- Ecole Polytechnique Fédérale de Lausanne, Laboratoire de Spectroscopie Ultrarapide, ISIC-FSB, Station 6, CH-1015 Lausanne, Switzerland
| | - Amal El Nahhas
- Ecole Polytechnique Fédérale de Lausanne, Laboratoire de Spectroscopie Ultrarapide, ISIC-FSB, Station 6, CH-1015 Lausanne, Switzerland
| | - Steve L. Johnson
- Swiss Light Source, Paul-Scherrer-Institut, CH-5232 PSI-Villigen, Switzerland
| | - Paul Beaud
- Swiss Light Source, Paul-Scherrer-Institut, CH-5232 PSI-Villigen, Switzerland
| | - Rafael Abela
- Swiss Light Source, Paul-Scherrer-Institut, CH-5232 PSI-Villigen, Switzerland
| | - Christian Bressler
- Ecole Polytechnique Fédérale de Lausanne, Laboratoire de Spectroscopie Ultrarapide, ISIC-FSB, Station 6, CH-1015 Lausanne, Switzerland
| | - Ivano Tavernelli
- Ecole Polytechnique Fédérale de Lausanne, Laboratoire de Chimie Et Biochimie Computationnelles, ISIC-FSB, CH-1015 Lausanne, Switzerland
| | - Christopher J. Milne
- Ecole Polytechnique Fédérale de Lausanne, Laboratoire de Spectroscopie Ultrarapide, ISIC-FSB, Station 6, CH-1015 Lausanne, Switzerland
| | - Majed Chergui
- Ecole Polytechnique Fédérale de Lausanne, Laboratoire de Spectroscopie Ultrarapide, ISIC-FSB, Station 6, CH-1015 Lausanne, Switzerland
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65
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Hiranuma Y, Kaniwa K, Shoji M, Mafuné F. Solvation structures of iodide on and below a surface of aqueous solution studied by photodetachment spectroscopy. J Phys Chem A 2011; 115:8493-7. [PMID: 21721573 DOI: 10.1021/jp204195t] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We investigated solvation structures of I(-) on and below a surface of an aqueous solution by photodetachment spectroscopy. An aqueous solution of an alkali halide was introduced to the vacuum as a continuous liquid flow (liquid beam), and the liquid beam was irradiated with a UV laser pulse. The intensity of electrons emitted from the surface by the laser excitation was measured as a function of wavelength (photodetachment spectroscopy), and we obtained absorption spectrum of I(-) on and below the solution surface. From the absorption spectrum, we found that I(-) starts to appear on the solution surface as the bulk NaI concentration increases. Similar concentration dependence was observed for the KI solution. We also found that I(-) located inside the solution is pushed to the surface, when NaCl is added to the solution. These changes are explained in terms of the difference in the polarizability of halide ions.
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Affiliation(s)
- Yojiro Hiranuma
- Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Tokyo 153-8902, Japan
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66
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Shoji M, Kaniwa K, Hiranuma Y, Maselli O, Mafuné F. Solvation Structure of I− and Na+ on the Surface of NaI Aqueous Solution Studied by Photodetachment Spectroscopy in Combination with Mass Spectrometry. J Phys Chem A 2011; 115:2148-54. [DOI: 10.1021/jp109685d] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Makoto Shoji
- Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902, Japan
| | - Keisuke Kaniwa
- Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902, Japan
| | - Yojiro Hiranuma
- Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902, Japan
| | - Olivia Maselli
- Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902, Japan
| | - Fumitaka Mafuné
- Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902, Japan
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67
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Chen X, Larsen DS, Bradforth SE, van Stokkum IHM. Broadband Spectral Probing Revealing Ultrafast Photochemical Branching after Ultraviolet Excitation of the Aqueous Phenolate Anion. J Phys Chem A 2011; 115:3807-19. [DOI: 10.1021/jp107935f] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | | | - Stephen E. Bradforth
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
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68
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Suzuki YI, Shen H, Tang Y, Kurahashi N, Sekiguchi K, Mizuno T, Suzuki T. Isotope effect on ultrafast charge-transfer-to-solvent reaction from I− to water in aqueous NaI solution. Chem Sci 2011. [DOI: 10.1039/c0sc00650e] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
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69
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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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70
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Torres-Alacan J, Kratz S, Vöhringer P. Independent pairs and Monte-Carlo simulations of the geminate recombination of solvated electrons in liquid-to-supercritical water. Phys Chem Chem Phys 2011; 13:20806-19. [DOI: 10.1039/c1cp21678c] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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71
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Buback J, Kullmann M, Langhojer F, Nuernberger P, Schmidt R, Würthner F, Brixner T. Ultrafast Bidirectional Photoswitching of a Spiropyran. J Am Chem Soc 2010; 132:16510-9. [DOI: 10.1021/ja1062746] [Citation(s) in RCA: 115] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Johannes Buback
- Institut für Physikalische und Theoretische Chemie and Institut für Organische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Martin Kullmann
- Institut für Physikalische und Theoretische Chemie and Institut für Organische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Florian Langhojer
- Institut für Physikalische und Theoretische Chemie and Institut für Organische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Patrick Nuernberger
- Institut für Physikalische und Theoretische Chemie and Institut für Organische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Ralf Schmidt
- Institut für Physikalische und Theoretische Chemie and Institut für Organische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Frank Würthner
- Institut für Physikalische und Theoretische Chemie and Institut für Organische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Tobias Brixner
- Institut für Physikalische und Theoretische Chemie and Institut für Organische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
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72
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Buchner F, Lübcke A, Heine N, Schultz T. Time-resolved photoelectron spectroscopy of liquids. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2010; 81:113107. [PMID: 21133461 DOI: 10.1063/1.3499240] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
We present a novel setup for the investigation of ultrafast dynamic processes in a liquid jet using time-resolved photoelectron spectroscopy. A magnetic-bottle type spectrometer with a high collection efficiency allows the very sensitive detection of photoelectrons emitted from a 10 μm thick liquid jet. This translates into good signal/noise ratio and rapid data acquisition making femtosecond time-resolved experiments feasible. We describe the experimental setup, a detailed spectrometer characterization based on the spectroscopy of nitric oxide in the gas phase, and results from femtosecond time-resolved experiments on sodium iodide solutions. The latter experiments reveal the formation and evolution of the solvated electron and we characterize two distinct spectral components corresponding to initially thermalized and unthermalized solvated electrons. The absence of dark states in photoionization, the direct measurement of electron binding energies, and the ability to resolve dynamic processes on the femtosecond time scale make time-resolved photoelectron spectroscopy from the liquid jet a very promising method for the characterization of photochemical processes in liquids.
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Affiliation(s)
- Franziska Buchner
- Max-Born-Institut für nichtlineare Optik und Kurzzeitspektroskopie, Max-Born-Strasse 2A, 12489 Berlin, Germany
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73
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Abstract
The dynamics of hydrated electrons at the water/air interface are investigated using time-resolved second-harmonic generation spectroscopy. Initial solvation occurs in approximately 1 ps, and the electron remains at the interface for >750 ps. The location of the electron relative to the dividing surface is investigated using surfactants, which show that the electron is hydrated in the interfacial region, below the dividing surface.
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Affiliation(s)
- D M Sagar
- Department of Chemistry, University of Durham, South Road, Durham DH1 3LE, UK
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74
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75
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76
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Fedorenko S. Two-state model of excess electron relaxation and geminate recombination in water and aqueous solutions. Chem Phys 2010. [DOI: 10.1016/j.chemphys.2010.03.027] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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77
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Glover WJ, Larsen RE, Schwartz BJ. First principles multielectron mixed quantum/classical simulations in the condensed phase. II. The charge-transfer-to-solvent states of sodium anions in liquid tetrahydrofuran. J Chem Phys 2010; 132:144102. [DOI: 10.1063/1.3352565] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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78
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Nese C, Unterreiner AN. Photochemical processes in ionic liquids on ultrafast timescales. Phys Chem Chem Phys 2010; 12:1698-708. [DOI: 10.1039/b916799b] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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79
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Tang Y, Shen H, Sekiguchi K, Kurahashi N, Mizuno T, Suzuki YI, Suzuki T. Direct measurement of vertical binding energy of a hydrated electron. Phys Chem Chem Phys 2010; 12:3653-5. [PMID: 20358061 DOI: 10.1039/b925741a] [Citation(s) in RCA: 131] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Ying Tang
- Japan Science and Technology Agency, CREST, Sanbancho, Chiyoda-ku, Tokyo 102-0075, Japan
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80
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Lübcke A, Buchner F, Heine N, Hertel IV, Schultz T. Time-resolved photoelectron spectroscopy of solvated electrons in aqueous NaI solution. Phys Chem Chem Phys 2010; 12:14629-34. [PMID: 20886131 DOI: 10.1039/c0cp00847h] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- Andrea Lübcke
- Max-Born-Institut für nichtlineare Optik und Kurzzeitspektroskopie, Max-Born-Strasse 2A, 12489 Berlin, Germany.
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81
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Larsen MC, Schwartz BJ. Searching for solvent cavities via electron photodetachment: The ultrafast charge-transfer-to-solvent dynamics of sodide in a series of ether solvents. J Chem Phys 2009; 131:154506. [DOI: 10.1063/1.3245864] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
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82
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Neves-Petersen MT, Klitgaard S, Pascher T, Skovsen E, Polivka T, Yartsev A, Sundström V, Petersen SB. Flash photolysis of cutinase: identification and decay kinetics of transient intermediates formed upon UV excitation of aromatic residues. Biophys J 2009; 97:211-26. [PMID: 19580759 DOI: 10.1016/j.bpj.2009.01.065] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2008] [Revised: 12/18/2008] [Accepted: 01/12/2009] [Indexed: 11/24/2022] Open
Abstract
Aromatic amino acids play an important role in ultraviolet (UV)-induced photochemical reactions in proteins. In this work, we aim at gaining insight into the photochemical reactions induced by near-UV light excitation of aromatic residues that lead to breakage of disulfide bridges in our model enzyme, Fusarium solani pisi cutinase, a lipolytic enzyme. With this purpose, we acquired transient absorption data of cutinase, with supplemental experimental data on tryptophan (Trp) and lysozyme as reference molecules. We here report formation kinetics and lifetimes of transient chemical species created upon UV excitation of aromatic residues in proteins. Two proteins, lysozyme and cutinase, as well as the free amino acid Trp, were studied under acidic, neutral, and alkaline conditions. The shortest-lived species is assigned to solvated electrons (lifetimes of a few microseconds to nanoseconds), whereas the longer-lived species are assigned to aromatic neutral and ionic radicals, Trp triplet states, and radical ionic disulphide bridges. The pH-dependent lifetimes of each species are reported. Solvated electrons ejected from the side chain of free Trp residues and aromatic residues in proteins were observed 12 ns after excitation, reaching a maximum yield after approximately 40 ns. It is interesting to note that the formation kinetics of solvated electrons is not pH-dependent and is similar in the different samples. On the other hand, a clear increase of the solvated electron lifetime is observed with increasing pH. This observation is correlated with H3O+ being an electron scavenger. Prolonged UV illumination of cutinase leads to a larger concentration of solvated electrons and to greater absorption at 410 nm (assigned to disulphide electron adduct RSSR *-), with concomitant faster decay kinetics and near disappearance of the Trp* radical peak at 330 nm, indicating possible additional formation of TyrO* formed upon reaction of Trp* with Tyr residues. Prolonged UV illumination of cutinase also leads to a larger concentration of free thiol groups, known to originate from the dissociation of RSSR *-. Additional mechanisms that may lead to the near disappearance of Trp(*) are discussed. Our study provides insight into one key UV-light-induced reaction in cutinase, i.e., light-induced disruption of disulphide bridges mediated by the excitation of aromatic residues. Knowledge about the nature of the formed species and their lifetimes is important for the understanding of UV-induced reactions in humans that lead to light-induced diseases, e.g., skin cancer and cataract formation.
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83
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Bressler C, Abela R, Chergui M. Exploiting EXAFS and XANES for time-resolved molecular structures in liquids. ACTA ACUST UNITED AC 2009. [DOI: 10.1524/zkri.2008.0030] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
Time-resolved X-ray absorption fine structure (XAFS) spectroscopy with picosecond temporal resolution is a new method to observe electronic and geometric structures of short-lived reaction intermediates. It combines an intense femtosecond laser source synchronized to the X-ray pulses delivered by a synchrotron Swiss light source (SLS). We present key experiments on charge transfer reactions as well as spin-crossover processes in coordination chemistry compounds next to solvation dynamics studies of photogenerated atomic radicals. These examples emphasize the observables at hand using ultrafast XAFS techniques, which include the density of states, full and even partial changes in oxidation state, and internuclear distances with milli-Angström accuracy. An outlook towards femtosecond studies and biologically relevant systems stresses the high potential of XAFS methods using new femtosecond X-ray sources like free electron lasers (XFELs).
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84
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Abstract
Solvated electrons, and hydrated electrons in particular, are important species in condensed phase chemistry, physics, and biology. Many studies have examined the formation mechanism, reactivity, spectroscopy, and dynamics of electrons in aqueous solution and other solvents, leading to a fundamental understanding of the electron-solvent interaction. However, key aspects of solvated electrons remain controversial, and the interaction between hydrated electrons and water is of central interest. For example, although researchers generally accept that hydrated electrons, eaq-, occupy solvent cavities, another picture suggests that the electron resides in a diffuse orbital localized on a H3O radical. In addition, researchers have proposed two physically distinct models for the relaxation mechanism when the electron is excited. These models, formulated to interpret condensed phase experiments, have markedly different timescales for the internal conversion from the excited p state to the ground s state.Studies of negatively charged clusters, such as (H2O)n- and I-(H2O)n, offer a complementary perspective for studying aqueous electron solvation. In this Account, we use time-resolved photoelectron spectroscopy (TRPES), a femtosecond pump-probe technique in which mass-selected anions are electronically excited and then photodetached at a series of delay times, to focus on time-resolved dynamics in these and similar species. In (H2O)n-,TRPES gives evidence for ultrafast internal conversion in clusters up to n=100. Extrapolation of these results yields a p-state lifetime of 50 fs in the bulk limit. This is in good agreement with the nonadiabatic solvation model, one of the models proposed for relaxation of eaq-. Similarly, experiments on (MeOH)n- up to n=450 give an extrapolated p-state lifetime of 150fs. TRPES investigations of I-(H2O)n and I-(CH3CN)n probe a different aspect of electron solvation dynamics. In these experiments,an ultraviolet pump pulse excites the cluster analog of the charge-transfer-to-solvent (CTTS) band, ejecting an electron from the iodide into the solvent network. The probe pulse then monitors the solvent response to this excess electron,specifically its stabilization via solvent rearrangement. In I-(H2O)n, the iodide sits outside the solvent network, as does the excess electron initially formed by CTTS excitation. However, the iodide in I-(CH3CN)n is internally solvated, and both experimental and theoretical evidence indicate that electrons in (CH3CN)n- are internally solvated. Hence, these experiments reflect the complex dynamics that ensue when the electron is photo detached within a highly confined solvent cavity.
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Affiliation(s)
- Oli T. Ehrler
- Department of Chemistry, University of California, Berkeley, California 94720, and Chemical Sciences Division, Lawrence Berkeley National Laboratories, Berkeley, California 94720
| | - Daniel M. Neumark
- Department of Chemistry, University of California, Berkeley, California 94720, and Chemical Sciences Division, Lawrence Berkeley National Laboratories, Berkeley, California 94720
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85
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Chandrasekhar N, Schalk O, Unterreiner AN. Femtosecond UV Excitation in Imidazolium-Based Ionic Liquids. J Phys Chem B 2008; 112:15718-24. [DOI: 10.1021/jp804861z] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- N. Chandrasekhar
- Institut für Physikalische Chemie, Lehrstuhl für Molekulare Physikalische Chemie, Universität Karlsruhe (TH), D-76128 Karlsruhe, Germany
| | - O. Schalk
- Institut für Physikalische Chemie, Lehrstuhl für Molekulare Physikalische Chemie, Universität Karlsruhe (TH), D-76128 Karlsruhe, Germany
| | - A.-N. Unterreiner
- Institut für Physikalische Chemie, Lehrstuhl für Molekulare Physikalische Chemie, Universität Karlsruhe (TH), D-76128 Karlsruhe, Germany
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86
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Ehrler OT, Griffin GB, Young RM, Neumark DM. Photoinduced Electron Transfer and Solvation in Iodide-doped Acetonitrile Clusters. J Phys Chem B 2008; 113:4031-7. [DOI: 10.1021/jp806856m] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Oli T. Ehrler
- Department of Chemistry, University of California, Berkeley, California 94720 and Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720
| | - Graham B. Griffin
- Department of Chemistry, University of California, Berkeley, California 94720 and Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720
| | - Ryan M. Young
- Department of Chemistry, University of California, Berkeley, California 94720 and Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720
| | - Daniel M. Neumark
- Department of Chemistry, University of California, Berkeley, California 94720 and Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720
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87
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Glover WJ, Larsen RE, Schwartz BJ. The roles of electronic exchange and correlation in charge-transfer-to-solvent dynamics: Many-electron nonadiabatic mixed quantum/classical simulations of photoexcited sodium anions in the condensed phase. J Chem Phys 2008; 129:164505. [DOI: 10.1063/1.2996350] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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88
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Cavanagh MC, Young RM, Schwartz BJ. The roles of the solute and solvent cavities in charge-transfer-to-solvent dynamics: Ultrafast studies of potasside and sodide in diethyl ether. J Chem Phys 2008; 129:134503. [DOI: 10.1063/1.2977995] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
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89
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Lampre I, Pernot P, Bonin J, Mostafavi M. Comparison of solvation dynamics of electrons in four polyols. Radiat Phys Chem Oxf Engl 1993 2008. [DOI: 10.1016/j.radphyschem.2008.05.040] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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90
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Shoshanim O, Ruhman S. Na− photolysis in THF: Charge transfer to solvent studied from the donors perspective in <10fs detail. J Chem Phys 2008; 129:044502. [DOI: 10.1063/1.2946701] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
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91
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92
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Winter B, Aziz EF, Ottosson N, Faubel M, Kosugi N, Hertel IV. Electron dynamics in charge-transfer-to-solvent states of aqueous chloride revealed by Cl- 2p resonant Auger-electron spectroscopy. J Am Chem Soc 2008; 130:7130-8. [PMID: 18461939 DOI: 10.1021/ja8009742] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Charge-transfer-to-solvent (CTTS) excited states of aqueous chloride are studied by a novel experimental approach based on resonant inner-shell photoexcitation, Cl(-)aq 2p --> e(i), i = 1-4, which denotes a series of excitations to lowest and higher CTTS states. These states are clearly identified through the occurrence of characteristic spectator Auger decays to double Cl 3p valence-hole states, where the CTTS states can be more stabilized as compared to single Cl(-)aq 2p core excitations and optical valence excitations. Furthermore, we have found for the first time that the CTTS electron e(i) bound by a single Cl 2p hole not only behaves as a spectator e(i) --> e'(i), bound by a double valence-hole state before relaxation of the excited electron (i) itself, but also shows electron dynamics to the relaxed lowest state, e(i) --> e'(1*). This interpretation is supported by ab initio calculations. The key to performing photoelectron and Auger-electron spectroscopy studies from aqueous solutions is the use of a liquid microjet in ultrahigh vacuum in conjunction with synchrotron radiation.
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Affiliation(s)
- Bernd Winter
- Max-Born-Institut für Nichtlineare Optik and Kurzzeitspektroskopie, Max-Born-Strasse 2A, D-12489 Berlin, Germany.
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93
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Affiliation(s)
- Xiyi Chen
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482;
| | - Stephen E. Bradforth
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482;
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94
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Schriever C, Barbatti M, Stock K, Aquino AJ, Tunega D, Lochbrunner S, Riedle E, de Vivie-Riedle R, Lischka H. The interplay of skeletal deformations and ultrafast excited-state intramolecular proton transfer: Experimental and theoretical investigation of 10-hydroxybenzo[h]quinoline. Chem Phys 2008. [DOI: 10.1016/j.chemphys.2007.10.021] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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95
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Bragg AE, Schwartz BJ. Ultrafast Charge-Transfer-to-Solvent Dynamics of Iodide in Tetrahydrofuran. 2. Photoinduced Electron Transfer to Counterions in Solution. J Phys Chem A 2008; 112:3530-43. [DOI: 10.1021/jp712039u] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Arthur E. Bragg
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California 90095-1569
| | - Benjamin J. Schwartz
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California 90095-1569
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96
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Bonin J, Lampre I, Pernot P, Mostafavi M. Solvation dynamics of electron produced by two-photon ionization of liquid polyols. III. Glycerol. J Phys Chem A 2008; 112:1880-6. [PMID: 18266344 DOI: 10.1021/jp710203v] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The solvation dynamics of excess electrons in glycerol have been measured by the pump-probe femtosecond laser technique at 333 K. The electrons are produced by two-photon absorption at 263 nm. The change in the induced absorbance is followed up to 450 ps in the spectral range from 440 to 720 nm. The transient signals of electron solvation have been analyzed by two kinetic models: a stepwise mechanism and a continuous relaxation model, using a Bayesian data analysis method. The results are compared with those previously published for ethylene glycol (J. Phys. Chem. A 2006, 110, 175) and for propanediols (J. Phys. Chem. A 2007, 111, 4902). From the comparison, it is pointed out that solvation dynamics in glycerol is very fast despite its high viscosity. This is interpreted as the existence of efficient traps for the electrons in glycerol with low potential energy. The small shift of the absorption band of the excess electron indicates that the potential of these traps is very close to that corresponding to the fully solvated electron.
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Affiliation(s)
- J Bonin
- Laboratoire de Chimie Physique/ELYSE, Université Paris-Sud 11, UMR 8000, Bât. 349, Orsay, F-91405, France, and CNRS, Orsay, F-91405, France
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97
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Bragg AE, Schwartz BJ. The ultrafast charge-transfer-to-solvent dynamics of iodide in tetrahydrofuran. 1. Exploring the roles of solvent and solute electronic structure in condensed-phase charge-transfer reactions. J Phys Chem B 2007; 112:483-94. [PMID: 18085770 DOI: 10.1021/jp076934s] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Although they represent the simplest possible charge-transfer reactions, the charge-transfer-to-solvent (CTTS) dynamics of atomic anions exhibit considerable complexity. For example, the CTTS dynamics of iodide in water are very different from those of sodide (Na-) in tetrahydrofuran (THF), leading to the question of the relative importance of the solvent and solute electronic structures in controlling charge-transfer dynamics. In this work, we address this issue by investigating the CTTS spectroscopy and dynamics of I- in THF, allowing us to make detailed comparisons to the previously studied I-/H2O and Na-/THF CTTS systems. Since THF is weakly polar, ion pairing with the counterion can have a substantial impact on the CTTS spectroscopy and dynamics of I- in this solvent. In this study, we have isolated "counterion-free" I- in THF by complexing the Na+ counterion with 18-crown-6 ether. Ultrafast pump-probe experiments reveal that THF-solvated electrons (e-THF) appear 380 +/- 60 fs following the CTTS excitation of "free" I- in THF. The absorption kinetics are identical at all probe wavelengths, indicating that the ejected electrons appear with no significant dynamic solvation but rather with their equilibrium absorption spectrum. After their initial appearance, ejected electrons do not exhibit any additional dynamics on time scales up to approximately 1 ns, indicating that geminate recombination of e-THF with its iodine atom partner does not occur. Competitive electron scavenging measurements demonstrate that the CTTS excited state of I- in THF is quite large and has contact with scavengers that are several nanometers away from the iodide ion. The ejection time and lack of electron solvation observed for I- in THF are similar to what is observed following CTTS excitation of Na- in THF. However, the relatively slow ejection time, the complete lack of dynamic solvation, and the large ejection distance/lack of recombination dynamics are in marked contrast to the CTTS dynamics observed for I- in water, in which fast electron ejection, substantial solvation, and appreciable recombination have been observed. These differences in dynamical behavior can be understood in terms of the presence of preexisting, electropositive cavities in liquid THF that are a natural part of its liquid structure; these cavities provide a mechanism for excited electrons to relocate to places in the liquid that can be nanometers away, explaining the large ejection distance and lack of recombination following the CTTS excitation of I- in THF. We argue that the lack of dynamic solvation observed following CTTS excitation of both I- and Na- in THF is a direct consequence of the fact that little additional relaxation is required once an excited electron nonadiabatically relaxes into one of the preexisting cavities. In contrast, liquid water contains no such cavities, and CTTS excitation of I- in water leads to local electron ejection that involves substantial solvent reorganization.
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Affiliation(s)
- Arthur E Bragg
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California 90095-1569, USA
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98
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Kołaski M, Lee HM, Pak C, Kim KS. Charge-Transfer-to-Solvent-Driven Dissolution Dynamics of I-(H2O)2-5 upon Excitation: Excited-State ab Initio Molecular Dynamics Simulations. J Am Chem Soc 2007; 130:103-12. [DOI: 10.1021/ja072427c] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Maciej Kołaski
- Department of Chemistry, Center for Superfunctional Materials, Pohang University of Science and Technology, San 31, Hyojadong, Namgu, Pohang 790-784, Korea
| | - Han Myoung Lee
- Department of Chemistry, Center for Superfunctional Materials, Pohang University of Science and Technology, San 31, Hyojadong, Namgu, Pohang 790-784, Korea
| | - Chaeho Pak
- Department of Chemistry, Center for Superfunctional Materials, Pohang University of Science and Technology, San 31, Hyojadong, Namgu, Pohang 790-784, Korea
| | - Kwang S. Kim
- Department of Chemistry, Center for Superfunctional Materials, Pohang University of Science and Technology, San 31, Hyojadong, Namgu, Pohang 790-784, Korea
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99
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Anderson KEH, Sewall SL, Cooney RR, Kambhampati P. Noise analysis and noise reduction methods in kilohertz pump-probe experiments. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2007; 78:073101. [PMID: 17672749 DOI: 10.1063/1.2755391] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
We analyze sources of noise in kilohertz frequency pump/probe experiments and present a method for reducing experimental noise by identifying and filtering noisy shots. The power spectrum of instrumental noise shows high frequency, small amplitude modulations which cannot be averaged out. A histogram analysis shows that low frequency, large amplitude signals pose a serious obstacle to signal averaging for improved signal to noise. In kilohertz frequency pump/probe experiments, this low frequency noise typically arises from laser scatter due to bubbles, dust, and defects. We quantify the effectiveness in analyzing and rejecting these large amplitude signals which can produce a hindrance to the effectiveness of signal averaging.
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Affiliation(s)
- Kevin E H Anderson
- Department of Chemistry, McGill University, Montreal, Quebec H3A 2K6, Canada
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100
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Soroushian B, Lampre I, Bonin J, Pernot P, Pommeret S, Mostafavi M. Solvation dynamics of the electron produced by two-photon ionization of liquid polyols. 1. Ethylene glycol. J Phys Chem A 2007; 110:1705-17. [PMID: 16450999 DOI: 10.1021/jp0540149] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Solvated electrons have been produced in ethylene glycol by two-photon ionization of the solvent with 263 nm femtosecond laser pulses. The two-photon absorption coefficient of ethylene glycol at 263 nm is determined to be beta = (2.1 +/- 0.2) x 10(-11) m W(-1). The dynamics of electron solvation in ethylene glycol has been studied by pump-probe transient absorption spectroscopy. So, time-resolved absorption spectra ranging from 430 to 710 nm have been measured. A blue shift of the spectra is observed for the first tens of picoseconds. Using the Bayesian data analysis method, the observed solvation dynamics are reconstructed with different models: stepwise mechanisms, continuous relaxation models, or combinations of stepwise and continuous relaxation. Comparison between models is in favor of continuous relaxation, which is mainly governed by solvent molecular motions.
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Affiliation(s)
- B Soroushian
- Laboratoire de Chimie Physique/ELYSE, UMR 8000 CNRS/Université Paris-Sud, Centre d'Orsay, Bât. 349, 91405 Orsay Cedex, France
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