1
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Dantus M. Ultrafast studies of elusive chemical reactions in the gas phase. Science 2024; 385:eadk1833. [PMID: 39116221 DOI: 10.1126/science.adk1833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2024] [Accepted: 06/11/2024] [Indexed: 08/10/2024]
Abstract
The chemical composition of the interstellar medium and planetary atmospheres is constantly in flux as atoms and molecules collide and interact with high-energy particles such as electrons, protons, and photons. These transformative processes ultimately lead to the coalescence of molecules and eventually the birth of stars. Our understanding of these chemical ecosystems relies on models that synthesize data from gas-phase experiments, providing insights into reaction cross sections. This Review examines efforts to delve into the fundamental bond-forming and bond-breaking dynamics that occur during bimolecular and electron-initiated reactions. These experiments involve clever approaches to establish a time reference and the collision geometry necessary for tracking atomic motion with femtosecond time resolution. Findings from these efforts enhance present models and improve predictions for molecule-molecule and electron-molecule collisions.
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Affiliation(s)
- Marcos Dantus
- Department of Chemistry, Michigan State University, East Lansing, MI 48824, USA
- Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824, USA
- Department of Electrical and Computer Engineering, Michigan State University, East Lansing, MI 48824, USA
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2
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Blackman K, Segrest E, Turner G, Machamer K, Gupta A, Khan Pathan MA, Berriel SN, Banerjee P, Vaida ME. Simultaneous tracking of ultrafast surface and gas-phase dynamics in solid-gas interfacial reactions. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2024; 95:083003. [PMID: 39133084 DOI: 10.1063/5.0217441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2024] [Accepted: 07/21/2024] [Indexed: 08/13/2024]
Abstract
Real-time detection of intermediate species and final products at the surface and near-surface in interfacial solid-gas reactions is critical for an accurate understanding of heterogeneous reaction mechanisms. In this article, an experimental method that can simultaneously monitor the ultrafast dynamics at the surface and above the surface in photoinduced heterogeneous reactions is presented. This method relies on a combination of mass spectrometry and femtosecond pump-probe spectroscopy. As a model system, the photoinduced reaction of methyl iodide on and above a cerium oxide surface is investigated. The species that are simultaneously detected from the surface and gas-phase present distinct features in the mass spectra, such as a sharp peak followed by an adjacent broad shoulder. The sharp peak is attributed to the species detected from the surface, while the broad shoulder is due to the detection of gas-phase species above the surface, as confirmed by multiple experiments. By monitoring the evolution of the sharp peak and broad shoulder as a function of the pump-probe time delay, transient signals are obtained that describe the ultrafast photoinduced reaction dynamics of methyl iodide on the surface and in the gas-phase. Finally, SimION simulations are performed to confirm the origin of the ions produced on the surface and in the gas-phase.
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Affiliation(s)
- Keith Blackman
- Department of Physics, University of Central Florida, Orlando, Florida 32816, USA
| | - Eric Segrest
- Department of Physics, University of Central Florida, Orlando, Florida 32816, USA
| | - George Turner
- Department of Physics, University of Central Florida, Orlando, Florida 32816, USA
| | - Kai Machamer
- Department of Physics, University of Central Florida, Orlando, Florida 32816, USA
| | - Aakash Gupta
- Department of Physics, University of Central Florida, Orlando, Florida 32816, USA
| | - Md Afjal Khan Pathan
- Department of Physics, University of Central Florida, Orlando, Florida 32816, USA
| | - S Novia Berriel
- Department of Material Science and Engineering, University of Central Florida, Orlando, Florida 32816, USA
| | - Parag Banerjee
- Department of Material Science and Engineering, University of Central Florida, Orlando, Florida 32816, USA
- Nano Science and Technology Center, University of Central Florida, Orlando, Florida 32816, USA
- Florida Solar Energy Center, University of Central Florida, Orlando, Florida 32816, USA
- Renewable Energy and Chemical Transformations Cluster, University of Central Florida, Orlando, Florida 32816, USA
| | - Mihai E Vaida
- Department of Physics, University of Central Florida, Orlando, Florida 32816, USA
- Renewable Energy and Chemical Transformations Cluster, University of Central Florida, Orlando, Florida 32816, USA
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3
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Jensen ET. Adsorbate dissociation due to heteromolecular electronic energy transfer from fluorobenzene thin films. Phys Chem Chem Phys 2024; 26:11910-11921. [PMID: 38568744 DOI: 10.1039/d3cp05520e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/18/2024]
Abstract
Study of the near-UV photodissociation dynamics for monolayer (ML) quantities of CH3I on thin films of a series of fluorobenzenes and benzene (1-25 ML) grown on a Cu(100) substrate finds that in addition to gas-phase-like neutral photodissociation, CH3I dissociation can be enhanced via electronic energy transfer to the CH3I following photoabsorption in several of the thin films studied. Distinct CH3 photofragment kinetic energy distributions are found for CH3I photodissociation on C6H5F, 1,4-C6H4F2 and C6H6 thin films, and distinguished from neutral photodissociation pathways using polarized incident light. The effective photodissociation cross section for CH3I on these thin films is increased as compared to that for the higher F-count fluorobenzene thin films due to the additional photodissociation pathway available. Quenching by the metal substrate of the photoexcitation via this new pathway suggests a significantly longer timescale for excitation than that of neutral CH3I photodissociation. The observations support a mechanism in which neutral photoexcitation in the thin film (i.e. an exciton) is transported to the interface with CH3I, and transfers the electronic excitation to the CH3I which then dissociates. The unimodal CH3 photofragment distribution and observed kinetic energies on the fluorobenzene thin films suggest that the dissociation occurs via the 3Q1 excited state of CH3I.
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Affiliation(s)
- E T Jensen
- Department of Physics, University of Northern BC, Canada.
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4
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Pathan MAK, Gupta A, Vaida ME. Understanding the Effect of an Amorphous Surface on the Ultrafast Dynamics of a Heterogeneous Photoinduced Reaction: CD 3I Photoinduced Reaction on Amorphous Cerium Oxide Films. J Phys Chem Lett 2022; 13:9759-9765. [PMID: 36226789 DOI: 10.1021/acs.jpclett.2c02294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
In this work, to understand how an amorphous surface influences the dynamics of surface photoinduced reactions, pump-probe spectroscopy in conjunction with mass spectrometry is employed to track the ultrafast evolution of intermediates and final products with time, mass, and energy resolution. As a model system, the photoinduced reaction of CD3I adsorbed on amorphous cerium oxide films is investigated. A fraction of the first intermediates produced on a freshly prepared surface is trapped to passivate the surface. After the A-band excitation, the minimum dissociation time of CD3I indicates that CD3I adsorption geometries with either CD3 or I facing the gas phase exist; however, the transient data suggest that most molecules are adsorbed with the I atom facing the surface. CD3 and I are consumed to form I2 and reform CD3I, which are produced at a steady rate only after the intermediates have lost the excess translational energy released from photodissociation.
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Affiliation(s)
- Md Afjal Khan Pathan
- Department of Physics, University of Central Florida, Orlando, Florida32816, United States
| | - Aakash Gupta
- Department of Physics, University of Central Florida, Orlando, Florida32816, United States
| | - Mihai E Vaida
- Department of Physics, University of Central Florida, Orlando, Florida32816, United States
- Renewable Energy and Chemical Transformations Cluster, University of Central Florida, Orlando, Florida32816, United States
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5
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Schouder CA, Chatterley AS, Pickering JD, Stapelfeldt H. Laser-Induced Coulomb Explosion Imaging of Aligned Molecules and Molecular Dimers. Annu Rev Phys Chem 2022; 73:323-347. [PMID: 35081323 DOI: 10.1146/annurev-physchem-090419-053627] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We discuss how Coulomb explosion imaging (CEI), triggered by intense femtosecond laser pulses and combined with laser-induced alignment and covariance analysis of the angular distributions of the recoiling fragment ions, provides new opportunities for imaging the structures of molecules and molecular complexes. First, focusing on gas phase molecules, we show how the periodic torsional motion of halogenated biphenyl molecules can be measured in real time by timed CEI, and how CEI of one-dimensionally aligned difluoroiodobenzene molecules can uniquely identify four structural isomers. Next, focusing on molecular complexes formed inside He nanodroplets, we show that the conformations of noncovalently bound dimers or trimers, aligned in one or three dimensions, can be determined by CEI. Results presented for homodimers of CS2, OCS, and bromobenzene pave the way for femtosecond time-resolved structure imaging of molecules undergoing bimolecular interactions and ultimately chemical reactions. Expected final online publication date for the Annual Review of Physical Chemistry, Volume 73 is April 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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6
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Long-lasting field-free alignment of large molecules inside helium nanodroplets. Nat Commun 2019; 10:133. [PMID: 30635554 PMCID: PMC6329814 DOI: 10.1038/s41467-018-07995-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Accepted: 12/05/2018] [Indexed: 11/09/2022] Open
Abstract
Molecules with their axes sharply confined in space, available through laser-induced alignment methods, are essential for many current experiments, including ultrafast molecular imaging. For these applications the aligning laser field should ideally be turned-off, to avoid undesired perturbations, and the strong alignment should last long enough that reactions and dynamics can be mapped out. Presently, this is only possible for small, linear molecules and for times less than 1 picosecond. Here, we demonstrate strong, field-free alignment of large molecules inside helium nanodroplets, lasting >10 picoseconds. One-dimensional or three-dimensional alignment is created by a slowly switched-on laser pulse, made field-free through rapid pulse truncation, and retained thanks to the impeding effect of the helium environment on molecular rotation. The opportunities field-free aligned molecules open are illustrated by measuring the alignment-dependent strong-field ionization yield of dibromothiophene oligomers. Our technique will enable molecular frame experiments, including ultrafast excited state dynamics, on a variety of large molecules and complexes.
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7
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Kohse-Höinghaus K, Troe J, Grabow JU, Olzmann M, Friedrichs G, Hungenberg KD. Kinetics in the real world: linking molecules, processes, and systems. Phys Chem Chem Phys 2018; 20:10561-10568. [PMID: 29616689 DOI: 10.1039/c8cp90054j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Unravelling elementary steps, reaction pathways, and kinetic mechanisms is key to understanding the behaviour of many real-world chemical systems that span from the troposphere or even interstellar media to engines and process reactors. Recent work in chemical kinetics provides detailed information on the reactive changes occurring in chemical systems, often on the atomic or molecular scale. The optimisation of practical processes, for instance in combustion, catalysis, battery technology, polymerisation, and nanoparticle production, can profit from a sound knowledge of the underlying fundamental chemical kinetics. Reaction mechanisms can combine information gained from theory and experiments to enable the predictive simulation and optimisation of the crucial process variables and influences on the system's behaviour that may be exploited for both monitoring and control. Chemical kinetics, as one of the pillars of Physical Chemistry, thus contributes importantly to understanding and describing natural environments and technical processes and is becoming increasingly relevant for interactions in and with the real world.
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8
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Bogomolov AS, Goldort VG, Kochubei SA, Baklanov AV. Photodissociation of van der Waals complexes of iodine X-I 2 (X = I 2, C 2H 4) via charge-transfer state: A velocity map imaging investigation. J Chem Phys 2017; 147:234304. [PMID: 29272931 DOI: 10.1063/1.5001104] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The photodissociation of van der Waals complexes of iodine X-I2 (X = I2, C2H4) excited via Charge-Transfer (CT) band has been studied with the velocity map imaging technique. Photodissociation of both complexes gives rise to translationally "hot" molecular iodine I2 via channels differing by kinetic energy and angular distribution of the recoil directions. These measured characteristics together with the analysis of the model potential energy surface for these complexes allow us to infer the back-electron-transfer (BET) in the CT state to be a source of observed photodissociation channels and to make conclusions on the location of conical intersections where the BET process takes place. The BET process is concluded to provide an I2 molecule in the electronic ground state with moderate vibrational excitation as well as X molecule in the electronic excited state. In the case of X = I2, the BET process converts anion I2- of the CT state into the neutral I2 in the repulsive excited electronic state which then dissociates promptly giving rise to a pair of I atoms in the fine states 2P1/2. In the case of C2H4-I2, the C2H4 molecules appear in the triplet T1 electronic state. Conical intersection for corresponding BET process becomes energetically accessible after partial twisting of C2H4+ frame in the excited CT state of complex. The C2H4(T)-I2 complex gives rise to triplet ethylene as well as singlet ethylene via the T-S conversion.
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9
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Chiu CC, Hung CC, Cheng PY. Ultrafast Charge Recombination Dynamics in Ternary Electron Donor–Acceptor Complexes: (Benzene)2-Tetracyanoethylene Complexes. J Phys Chem B 2016; 120:12390-12403. [DOI: 10.1021/acs.jpcb.6b10593] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Chih-Chung Chiu
- Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan 30043, R. O. C
| | - Chih-Chang Hung
- Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan 30043, R. O. C
| | - Po-Yuan Cheng
- Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan 30043, R. O. C
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10
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Aly SM, AbdulHalim LG, Besong TMD, Soldan G, Bakr OM, Mohammed OF. Ultrafast static and diffusion-controlled electron transfer at Ag29 nanocluster/molecular acceptor interfaces. NANOSCALE 2016; 8:5412-6. [PMID: 26548942 DOI: 10.1039/c5nr05328e] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Efficient absorption of visible light and a long-lived excited state lifetime of silver nanoclusters (Ag29 NCs) are integral properties for these new clusters to serve as light-harvesting materials. Upon optical excitation, electron injection at Ag29 NC/methyl viologen (MV(2+)) interfaces is very efficient and ultrafast. Interestingly, our femto- and nanosecond time-resolved results demonstrate clearly that both dynamic and static electron transfer mechanisms are involved in photoluminescence quenching of Ag29 NCs.
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Affiliation(s)
- Shawkat M Aly
- Solar and Photovoltaics Engineering Research Center, Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia.
| | - Lina G AbdulHalim
- Solar and Photovoltaics Engineering Research Center, Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia.
| | - Tabot M D Besong
- Solar and Photovoltaics Engineering Research Center, Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia.
| | - Giada Soldan
- Solar and Photovoltaics Engineering Research Center, Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia.
| | - Osman M Bakr
- Solar and Photovoltaics Engineering Research Center, Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia.
| | - Omar F Mohammed
- Solar and Photovoltaics Engineering Research Center, Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia.
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11
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Kalume A, George L, Powell AD, Dawes R, Reid SA. Photoinduced electron transfer in donor-acceptor complexes of ethylene with molecular and atomic iodine. J Phys Chem A 2014; 118:6838-45. [PMID: 25075444 DOI: 10.1021/jp412212h] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Building upon our recent studies of radical addition pathways following excitation of the I2 chromophore in the donor-acceptor complex of ethylene and I2 (C2H4···I2), in this article, we extend our studies to examine photoinduced electron transfer. Thus, irradiation into the intense charge-transfer band of the complex (λmax = 247 nm) gave rise to a band at 366 nm that is assigned to the bridged ethylene-I radical complex on the basis of our prior work. The formation of the radical complex is explained by a mechanism that involves rapid back electron transfer leading to I-I bond fission. Excitation into the charge-transfer band of the radical complex led to regeneration of the parent complex and the formation of the final photoproduct, anti- and gauche-1,2-diiodoethane, which confirms that the reaction proceeds ultimately by a radical addition mechanism. This finding is contrasted with our previous study of the C2H4···Br2 complex, where CT excitation led to only one product, anti-1,2-dibromoethane, a result explained by a single electron-transfer mechanism proceeding via a bridged bromonium ion intermediate. For the I2 complex, the breakup of the photolytically generated I2(-•) anion radical is apparently sufficiently slow to render it uncompetitive with back electron transfer. Finally, we report a detailed computational examination of the parent and radical complexes of both bromine and iodine, using high-level single- and multireference methods, which provide insight into the different behaviors of the charge-transfer states of the two radicals and the role of spin-orbit coupling.
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Affiliation(s)
- Aimable Kalume
- Department of Chemistry, Marquette University , Milwaukee, Wisconsin 53233, United States
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12
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El-Ballouli AO, Alarousu E, Bernardi M, Aly SM, Lagrow AP, Bakr OM, Mohammed OF. Quantum Confinement-Tunable Ultrafast Charge Transfer at the PbS Quantum Dot and Phenyl-C61-butyric Acid Methyl Ester Interface. J Am Chem Soc 2014; 136:6952-9. [DOI: 10.1021/ja413254g] [Citation(s) in RCA: 91] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Ala’a O. El-Ballouli
- Solar
and Photovoltaics Engineering Research Center, Division of Physical
Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Erkki Alarousu
- Solar
and Photovoltaics Engineering Research Center, Division of Physical
Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Marco Bernardi
- Department
of Physics, University of California at Berkeley, Berkeley, California 94720-7300, United States
| | - Shawkat M. Aly
- Solar
and Photovoltaics Engineering Research Center, Division of Physical
Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Alec P. Lagrow
- Solar
and Photovoltaics Engineering Research Center, Division of Physical
Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Osman M. Bakr
- Solar
and Photovoltaics Engineering Research Center, Division of Physical
Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Omar F. Mohammed
- Solar
and Photovoltaics Engineering Research Center, Division of Physical
Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
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13
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Piacente G, Amadei A, D'Abramo M, Daidone I, Aschi M. Theoretical-computational modeling of photo-induced charge separation spectra and charge recombination kinetics in solution. Phys Chem Chem Phys 2014; 16:20624-38. [DOI: 10.1039/c4cp02422b] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A computational approach, based on molecular dynamics simulations and quantum-chemical calculations, is proposed for modelling the photo-induced charge separation and the kinetics of the subsequent charge recombination (CR) processes in solution.
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Affiliation(s)
- Giovanni Piacente
- Dipartimento di Scienze Fisiche e Chimiche Universita' di l'Aquila
- Via Vetoio s.n.c. 87100 l'Aquila, Italy
| | - Andrea Amadei
- Dipartimento di Scienze e Tecnologie Chimiche Universita' di Roma ‘Tor Vergata’
- Via della Ricerca Scientifica 00100 Roma, Italy
| | - Marco D'Abramo
- Dipartimento di Chimica Universita' di Roma ‘La Sapienza’
- 00185 Roma, Italy
| | - Isabella Daidone
- Dipartimento di Scienze Fisiche e Chimiche Universita' di l'Aquila
- Via Vetoio s.n.c. 87100 l'Aquila, Italy
| | - Massimiliano Aschi
- Dipartimento di Scienze Fisiche e Chimiche Universita' di l'Aquila
- Via Vetoio s.n.c. 87100 l'Aquila, Italy
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14
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He TF, Guo L, Guo X, Chang CW, Wang L, Zhong D. Femtosecond dynamics of short-range protein electron transfer in flavodoxin. Biochemistry 2013; 52:9120-8. [PMID: 24289221 PMCID: PMC3909472 DOI: 10.1021/bi401137u] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Intraprotein electron transfer (ET) in flavoproteins is important for understanding the correlation of their redox, configuration, and reactivity at the active site. Here, we used oxidized flavodoxin as a model system and report our complete characterization of a photoinduced redox cycle from the initial charge separation in 135-340 fs to subsequent charge recombination in 0.95-1.6 ps and to the final cooling relaxation of the product(s) in 2.5-4.3 ps. With 11 mutations at the active site, we observed that these ultrafast ET dynamics, much faster than active-site relaxation, mainly depend on the reduction potentials of the electron donors with minor changes caused by mutations, reflecting a highly localized ET reaction between the stacked donor and acceptor at a van der Waals distance and leading to a gas-phase type of bimolecular ET reaction confined in the active-site nanospace. Significantly, these ultrafast ET reactions ensure our direct observation of vibrationally excited reaction product(s), suggesting that the back ET barrier is effectively reduced because of the decrease in the total free energy in the Marcus inverted region, leading to the accelerated charge recombination. Such vibrationally coupled charge recombination should be a general feature of flavoproteins with similar configurations and interactions between the cofactor flavin and neighboring aromatic residues.
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Affiliation(s)
| | | | - Xunmin Guo
- Department of Physics, Department of Chemistry and Biochemistry, and Programs of Biophysics, Chemical Physics, and Biochemistry, The Ohio State University, Columbus, OH 43210
| | - Chih-Wei Chang
- Department of Physics, Department of Chemistry and Biochemistry, and Programs of Biophysics, Chemical Physics, and Biochemistry, The Ohio State University, Columbus, OH 43210
| | - Lijuan Wang
- Department of Physics, Department of Chemistry and Biochemistry, and Programs of Biophysics, Chemical Physics, and Biochemistry, The Ohio State University, Columbus, OH 43210
| | - Dongping Zhong
- Department of Physics, Department of Chemistry and Biochemistry, and Programs of Biophysics, Chemical Physics, and Biochemistry, The Ohio State University, Columbus, OH 43210
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15
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Chiu CC, Hung CC, Chen CL, Cheng PY. Ultrafast Time-Resolved Broadband Fluorescence Studies of the Benzene-Tetracyanoethylene Complex: Solvation, Vibrational Relaxation, and Charge Recombination Dynamics. J Phys Chem B 2013; 117:9734-56. [DOI: 10.1021/jp404615u] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Chih-Chung Chiu
- Department
of Chemistry, National Tsing Hua University, Hsinchu, Taiwan 30043, Republic of China
| | - Chih-Chang Hung
- Department
of Chemistry, National Tsing Hua University, Hsinchu, Taiwan 30043, Republic of China
| | - Chien-Lin Chen
- Department
of Chemistry, National Tsing Hua University, Hsinchu, Taiwan 30043, Republic of China
| | - Po-Yuan Cheng
- Department
of Chemistry, National Tsing Hua University, Hsinchu, Taiwan 30043, Republic of China
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16
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Wada Y, Morisawa Y, Wakabayashi T. Spectroscopic characterization of a series of polyyne–iodine molecular complexes H(CC)nH(I6) of n=5–9. Chem Phys Lett 2012. [DOI: 10.1016/j.cplett.2012.05.035] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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17
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Peralta Conde A, Ovejas V, Montero R, Castaño F, Longarte A. Influence of solvation on the indole photophysics: Ultrafast dynamics of indole–water clusters. Chem Phys Lett 2012. [DOI: 10.1016/j.cplett.2012.01.060] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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18
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Conductivity by Electron Pairs. Chem Phys 2012. [DOI: 10.1201/b11524-20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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19
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Wada Y, Wakabayashi T, Kato T. Photoinduced Reaction of Hydrogen-End-Capped Polyynes with Iodine Molecules. J Phys Chem B 2011; 115:8439-45. [DOI: 10.1021/jp203074r] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Yoriko Wada
- Department of Chemistry, Kinki University, Higashi-Osaka 577-8502, Japan
| | | | - Tatsuhisa Kato
- Institute for the Promotion of Excellence in Higher Education, Kyoto University, Kyoto 606-8501, Japan
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20
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Deng Y, Feng X, Zhou M, Qian Y, Yu H, Qiu X. Investigation of Aggregation and Assembly of Alkali Lignin Using Iodine as a Probe. Biomacromolecules 2011; 12:1116-25. [DOI: 10.1021/bm101449b] [Citation(s) in RCA: 131] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Yonghong Deng
- State Key Lab of Pulp and Paper Engineering, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, 510640, People's Republic of China
| | - Xinjia Feng
- State Key Lab of Pulp and Paper Engineering, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, 510640, People's Republic of China
| | - Mingsong Zhou
- State Key Lab of Pulp and Paper Engineering, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, 510640, People's Republic of China
| | - Yong Qian
- State Key Lab of Pulp and Paper Engineering, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, 510640, People's Republic of China
| | - Haifeng Yu
- Top Runner Incubation Center for Academia-Industry Fusion, and Department of Materials Science and Technology, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka 940-2188, Japan
| | - Xueqing Qiu
- State Key Lab of Pulp and Paper Engineering, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, 510640, People's Republic of China
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Mohammed OF. Ultrafast Intramolecular Charge Transfer of Formyl Perylene Observed Using Femtosecond Transient Absorption Spectroscopy. J Phys Chem A 2010; 114:11576-82. [DOI: 10.1021/jp107256f] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Omar F. Mohammed
- Physical Biology Center for Ultrafast Science & Technology, Arthur Amos Noyes Laboratory of Chemical Physics, California Institute of Technology, Pasadena, California 91125, United States, and Chemistry Department, Faculty of Science, Assiut University, Assiut 71516, Egypt
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22
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Esseffar M, El Messaoudi M, Bouab W. Experimental and theoretical study on 3,5-(oxo/thioxo) derivatives of 2,7-dimethyl-1,2,4-triazepines-iodine molecular complexes. J PHYS ORG CHEM 2009. [DOI: 10.1002/poc.1539] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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23
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Kiviniemi T, Hulkko E, Kiljunen T, Pettersson M. Iodine−Benzene Complex as a Candidate for a Real-Time Control of a Bimolecular Reaction. Spectroscopic Studies of the Properties of the 1:1 Complex Isolated in Solid Krypton. J Phys Chem A 2009; 113:6326-33. [DOI: 10.1021/jp902012u] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Tiina Kiviniemi
- Nanoscience Center, Department of Chemistry, P.O. Box 35, FI-40014 University of Jyväskylä, Finland
| | - Eero Hulkko
- Nanoscience Center, Department of Chemistry, P.O. Box 35, FI-40014 University of Jyväskylä, Finland
| | - Toni Kiljunen
- Nanoscience Center, Department of Chemistry, P.O. Box 35, FI-40014 University of Jyväskylä, Finland
| | - Mika Pettersson
- Nanoscience Center, Department of Chemistry, P.O. Box 35, FI-40014 University of Jyväskylä, Finland
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24
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Kim HY, Salvi L, Carroll PJ, Walsh PJ. Highly enantio- and diastereoselective one-pot methods for the synthesis of halocyclopropyl alcohols. J Am Chem Soc 2009; 131:954-62. [PMID: 19154172 DOI: 10.1021/ja806989n] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The lack of methods for the stereoselective transfer of functionalized carbenoids is one of the most significant deficiencies of Simmons-Smith cyclopropanation reactions. Outlined herein are one-pot methods for the catalytic asymmetric synthesis of halocyclopropyl alcohols with up to four stereogenic centers from achiral starting materials. The first method involves asymmetric alkyl addition to a conjugated enal to generate an allylic alkoxide followed by tandem diastereoselective iodo-, bromo-, or chlorocyclopropanation to furnish halocyclopropyl alcohols. Enantioselectivities in these processes range from 89-99%, and dr's of >20:1 were achieved with all substrates optimized. The second method consists of an asymmetric vinylation of a saturated or aromatic aldehyde followed by a diastereoselective iodocyclopropanation to produce iodocyclopropyl alcohols with enantioselectivities between 86 and 99% and dr's of >20:1. These complementary methods enable the efficient synthesis of a variety of halocyclopropyl alcohols in one-pot procedures. Preliminary efforts to functionalize iodocyclopropanes involve reaction with an excess of LiCu(n-Bu)(2) to generate the cyclopropyl cuprate. This intermediate can be quenched with allyl bromides to generate the allylated cyclopropyl alcohols without loss of enantio- or diastereoselectivity.
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Affiliation(s)
- Hun Young Kim
- P. Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104-6323, USA
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25
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Ho JW, Chen WK, Cheng PY. Unraveling Complex Three-Body Photodissociation Dynamics of Dimethyl Sulfoxide: A Femtosecond Time-Resolved Spectroscopic Study. J Phys Chem A 2008; 112:10453-68. [DOI: 10.1021/jp804847y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jr-Wei Ho
- Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan, R. O. C
| | - Wei-Kan Chen
- Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan, R. O. C
| | - Po-Yuan Cheng
- Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan, R. O. C
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26
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Qiu W, Li T, Zhang L, Yang Y, Kao YT, Wang L, Zhong D. Ultrafast quenching of tryptophan fluorescence in proteins: Interresidue and intrahelical electron transfer. Chem Phys 2008. [DOI: 10.1016/j.chemphys.2008.01.061] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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27
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Kiviniemi T, Hulkko E, Kiljunen T, Pettersson M. Vibrational Characterization of the 1:1 Iodine−Benzene Complex Isolated in Solid Krypton. J Phys Chem A 2008; 112:5025-7. [DOI: 10.1021/jp801980k] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Tiina Kiviniemi
- Nanoscience Center, Department of Chemistry, P.O. Box 35, FI−40014 University of Jyväskylä, Finland
| | - Eero Hulkko
- Nanoscience Center, Department of Chemistry, P.O. Box 35, FI−40014 University of Jyväskylä, Finland
| | - Toni Kiljunen
- Nanoscience Center, Department of Chemistry, P.O. Box 35, FI−40014 University of Jyväskylä, Finland
| | - Mika Pettersson
- Nanoscience Center, Department of Chemistry, P.O. Box 35, FI−40014 University of Jyväskylä, Finland
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28
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Chen WK, Cheng PY. Ultrafast photodissociation dynamics of acetone at 195 nm: II. Unraveling complex three-body dissociation dynamics by femtosecond time-resolved photofragment translational spectroscopy. J Phys Chem A 2007; 109:6818-29. [PMID: 16834037 DOI: 10.1021/jp0509717] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
As a continuation of the preceding paper in this issue (J. Phys. Chem. A 2005, 109, 6805), we studied photodissociation dynamics of the acetone S2 (n, 3s) Rydberg state excited at 195 nm using femtosecond time-resolved photofragment translational spectroscopy. The technique, which is implemented by the combination of fs pump-probe ionization spectroscopy and kinetic energy resolved time-of-flight mass spectrometry (KETOF), measured temporal evolutions of the product kinetic energy distributions (KEDs) with a time resolution limited only by the laser pulse widths. Two methyl product KED components were resolved and assigned to the primary and secondary methyl products on the basis of their temporal behaviors. The results support the mechanism in which the primary dissociation occurs on the acetone S1 surface and provide complementary dynamical information to that discussed in the preceding paper.
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Affiliation(s)
- Wei-Kan Chen
- Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan, ROC
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29
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Kao YT, Saxena C, Wang L, Sancar A, Zhong D. Femtochemistry in enzyme catalysis: DNA photolyase. Cell Biochem Biophys 2007; 48:32-44. [PMID: 17703066 DOI: 10.1007/s12013-007-0034-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/1999] [Revised: 11/30/1999] [Accepted: 11/30/1999] [Indexed: 10/23/2022]
Abstract
Photolyase uses light energy to split UV-induced cyclobutane pyrimidine dimers in damaged DNA. This photoenzyme encompasses a series of elementary dynamical processes during repair function from early photoinitiation by a photoantenna molecule to enhance repair efficiency, to in vitro photoreduction through aromatic residues to reconvert the cofactor to the active form, and to final photorepair to fix damaged DNA. The corresponding series of dynamics include resonance energy transfer, intraprotein electron transfer, and intermolecular electron transfer, bond breaking-making rearrangements and back electron return, respectively. We review here our recent direct studies of these dynamical processes in real time, which showed that all these elementary reactions in the enzyme occur within subnanosecond timescale. Active-site solvation was observed to play a critical role in the continuous modulation of catalytic reactions. As a model system for enzyme catalysis, we isolated the enzyme-substrate complex in the transition-state region and mapped out the entire evolution of unmasked catalytic reactions of DNA repair. These observed synergistic motions in the active site reveal a perfect correlation of structural integrity and dynamical locality to ensure maximum repair efficiency on the ultrafast time scale.
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Affiliation(s)
- Ya-Ting Kao
- Department of Physics, Chemistry, and Biochemistry, Programs of Biophysics, Chemical Physics, and Biochemistry, The Ohio State University, Columbus, OH 43210, USA
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30
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Baklanov AV, Bogdanchikov GA, Vidma KV, Chestakov DA, Parker DH. Cluster-enhanced X–O2 photochemistry (X=CH3I, C3H6, C6H12, and Xe). J Chem Phys 2007; 126:124316. [PMID: 17411132 DOI: 10.1063/1.2710268] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The effect of a local environment on the photodissociation of molecular oxygen is investigated in the van der Waals complex X-O(2) (X=CH(3)I, C(3)H(6), C(6)H(12), and Xe). A single laser operating at wavelengths around 226 nm is used for both photodissociation of the van der Waals complex and simultaneous detection of the O((3)P(J),J=2,1,0) atom photoproduct via (2+1) resonance enhanced multiphoton ionization. The kinetic energy distribution (KED) and angular anisotropy of the product O atom recoil in this dissociation are measured using the velocity map imaging technique configured for either full ("crush") or partial ("slice") detection of the three-dimensional O((3)P(J)) atom product Newton sphere. The measured KED and angular anisotropy reveal a distinct difference in the mechanism of O atom generation from an X-O(2) complex compared to a free O(2) molecule. The authors identify two one-photon excitation pathways, the relative importance of which depends on IPx, the ionization potential of the X partner. One pathway, observed for all complexes independent of IPx, involves a direct transition to the perturbed covalent state X-O(2)(A'(3)Delta(u)) with excitation localized on the O(2) subunit. The predominantly perpendicular character of this channel relative to the laser polarization detection, together with data on the structure of the complex, allows us to confirm that X partner induced admixing of an X(+)-O(2) (-) charge transfer (CT) state is the perturbing factor resulting in the well-known enhancement of photoabsorption within the Herzberg continuum of molecular oxygen. The second excitation pathway, observed for X-O(2) complexes with X=CH(3)I and C(3)H(6), involves direct excitation into the (3)(X(+)-O(2) (-)) CT state of the complex. The subsequent photodissociation of this CT state by the same laser pulse gives rise to the superoxide anion O(2) (-), which then photodissociates, providing fast (0.69 eV) O atoms with a parallel image pattern. Products from the photodissociation of singlet oxygen O(2)(b (1)Sigma(g) (+)) are also observed when the CH(3)I-O(2) complex was irradiated. Potential energy surfaces (PES) for the ground and relevant excited states of the X-O(2) complex have been constructed for CH(3)I-O(2) using the results of CASSCF calculations for the ground and CT states of the complex as well as literature data on PES of the subunits. These model potential energy surfaces allowed us to interpret all of the observed O((3)P(J)) atom production channels.
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Affiliation(s)
- Alexey V Baklanov
- Institute of Chemical Kinetics and Combustion, Institutskaja Street 3, Novosibirsk, Russia
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31
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32
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Cheng PY, Baskin JS, Zewail AH. Dynamics of clusters: from elementary to biological structures. Proc Natl Acad Sci U S A 2006; 103:10570-6. [PMID: 16740669 PMCID: PMC1502273 DOI: 10.1073/pnas.0507114103] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Between isolated atoms or molecules and bulk materials there lies a class of unique structures, known as clusters, that consist of a few to hundreds of atoms or molecules. Within this range of "nanophase," many physical and chemical properties of the materials evolve as a function of cluster size, and materials may exhibit novel properties due to quantum confinement effects. Understanding these phenomena is in its own rights fundamental, but clusters have the additional advantage of being controllable model systems for unraveling the complexity of condensed-phase and biological structures, not to mention their vanguard role in defining nanoscience and nanotechnology. Over the last two decades, much progress has been made, and this short overview highlights our own involvement in developing cluster dynamics, from the first experiments on elementary systems to model systems in the condensed phase, and on to biological structures.
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Affiliation(s)
| | - J. Spencer Baskin
- Laboratory for Molecular Sciences, Arthur Amos Noyes Laboratory of Chemical Physics, California Institute of Technology, Pasadena, CA 91125
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33
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Weng KF, Shi Y, Zheng X, Phillips DL. Resonance Raman Investigation of the Short-Time Photodissociation Dynamics of the Charge-Transfer Absorption of the I2−Benzene Complex in Benzene Solution. J Phys Chem A 2005; 110:851-60. [PMID: 16419981 DOI: 10.1021/jp055069d] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Resonance Raman spectra were obtained for the I2-benzene complex in benzene solvent with excitation wavelengths in resonance with the CT-band absorption. These spectra indicate that the Franck-Condon region photodissociation dynamics have multidimensional character with motion mainly along the nominal I-I stretch mode nu(18), the nominal symmetric benzene ring stretch mode nu5, and the nominal symmetric CCH bending nu7. There is also a small contribution from the nominal out-of-plane CH oop wag nu15. A preliminary resonance Raman intensity analysis was done, and the results for the I2-benzene complex were compared to results previously reported for the 1-hexene-I2 complex. We briefly discuss the differences and similarities in the CT-band absorption excitation of an I2-benzene complex relative to those of an I2-alkene complex.
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Affiliation(s)
- Ke-Feng Weng
- Department of Applied Chemistry, Zhejiang Sci-Tech University, Second Road, Xia Sha Gao Jiao Yuan Qu Hangzhou 310033, P. R. China
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35
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Wang H, Saxena C, Quan D, Sancar A, Zhong D. Femtosecond Dynamics of Flavin Cofactor in DNA Photolyase: Radical Reduction, Local Solvation, and Charge Recombination. J Phys Chem B 2005; 109:1329-33. [PMID: 16851098 DOI: 10.1021/jp044652b] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We report here our femtosecond studies of the photoreduction dynamics of the neutral radical flavin (FADH) cofactor in E. coli photolyase, a process converting the inactive form to the biologically active one, a fully reduced deprotonated flavin FADH(-). The observed temporal absorption evolution revealed two initial electron-transfer reactions, occurring in 11 and 42 ps with the neighboring aromatic residues of W382 and F366, respectively. The new transient absorption, observed at 550 nm previously in photolyase, was found from the excited-state neutral radical and is probably caused by strong interactions with the adenine moiety through the flavin U-shaped configuration and the highly polar/charged surrounding residues. The solvation dynamics from the locally ordered water molecules in the active site was observed to occur in approximately 2 ps. These ultrafast ordered-water motions are critical to stabilizing the photoreduction product FADH(-) instantaneously to prevent fast charge recombination. The back electron-transfer reaction was found to occur in approximately 3 ns. This slow process, consistent with ultrafast stabilization of the catalytic cofactor, favors photoreduction in photolyase.
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Affiliation(s)
- Haiyu Wang
- Departments of Physics, Chemistry, and Biochemistry, OSU Biophysics, Chemical Physics, and Biochemistry Programs, 174 West 18th Avenue, The Ohio State University, Columbus, OH 43210, USA
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36
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Asseily GA, Davies RP, Rzepa HS, White AJP. A solid-state structural and theoretical study on the 1 ∶ 1 addition compounds of thioethers with dihalogens and interhalogens I–X (X = I, Br, Cl). NEW J CHEM 2005. [DOI: 10.1039/b411873a] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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37
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Rini M, Pines D, Magnes BZ, Pines E, Nibbering ETJ. Bimodal proton transfer in acid-base reactions in water. J Chem Phys 2004; 121:9593-610. [PMID: 15538881 DOI: 10.1063/1.1804172] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We investigate one of the fundamental reactions in solutions, the neutralization of an acid by a base. We use a photoacid, 8-hydroxy-1,3,6-trisulfonate-pyrene (HPTS; pyranine), which upon photoexcitation reacts with acetate under transfer of a deuteron (solvent: deuterated water). We analyze in detail the resulting bimodal reaction dynamics between the photoacid and the base, the first report on which was recently published. We have ascribed the bimodal proton-transfer dynamics to contributions from preformed hydrogen bonding complexes and from initially uncomplexed acid and base. We report on the observation of an additional (6 ps)(-1) contribution to the reaction rate constant. As before, we analyze the slower part of the reaction within the framework of the diffusion model and the fastest part by a static, sub-150 fs reaction rate. Adding the second static term considerably improves the overall modeling of the experimental results. It also allows to connect experimentally the diffusion controlled bimolecular reaction models as defined by Eigen-Weller and by Collins-Kimball. Our findings are in agreement with a three-stage mechanism for liquid phase intermolecular proton transfer: mutual diffusion of acid and base to form a "loose" encounter complex, followed by reorganization of the solvent shells and by "tightening" of the acid-base encounter complex. These rearrangements last a few picoseconds and enable a prompt proton transfer along the reaction coordinate, which occurs faster than our time resolution of 150 fs. Alternative models for the explanation of the slower "on-contact" reaction time of the loose encounter complex in terms of proton transmission through a von Grotthuss mechanism are also discussed.
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Affiliation(s)
- Matteo Rini
- Max Born Institut fuer Nichtlineare Optik und Kurzzeitspektroskopie, Max Born Strasse 2A, D-12489 Berlin, Germany
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38
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Tang LT, Wei Y, Wang Y, Hu SW, Liu XQ, Chu TW, Wang XY. A density functional study on the formation of charge transfer complexes between alkaloids and iodine monochloride. ACTA ACUST UNITED AC 2004. [DOI: 10.1016/j.theochem.2004.07.026] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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39
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Barr J, Torres I, Verdasco E, Bañares L, Aoiz FJ, Martínez-Haya B. Photodissociation Dynamics of Dimethyl Sulfide Following Excitation within the First Absorption Band. J Phys Chem A 2004. [DOI: 10.1021/jp049344s] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jonathan Barr
- Departamento de Química Física, Facultad de Química, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - Inmaculada Torres
- Departamento de Química Física, Facultad de Química, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - Enrique Verdasco
- Departamento de Química Física, Facultad de Química, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - Luis Bañares
- Departamento de Química Física, Facultad de Química, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - F. J. Aoiz
- Departamento de Química Física, Facultad de Química, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - Bruno Martínez-Haya
- Departamento de Ciencias Ambientales, Universidad Pablo de Olavide, 41013 Sevilla, Spain
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40
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Affiliation(s)
- T E Dermota
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
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41
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Chen WK, Ho JW, Cheng PY. Ultrafast photodissociation dynamics of the acetone 3s Rydberg state at 195 nm: a new mechanism. Chem Phys Lett 2003. [DOI: 10.1016/j.cplett.2003.09.039] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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42
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Parsons BF, Chandler DW. On the Dissociation of van der Waals Clusters of X2−Cyclohexane (X = O, Cl) Following Charge-Transfer Excitation in the Ultraviolet. J Phys Chem A 2003. [DOI: 10.1021/jp0301150] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Bradley F. Parsons
- Sandia National Laboratories, Combustion Research Facility, Livermore, California 94550
| | - David W. Chandler
- Sandia National Laboratories, Combustion Research Facility, Livermore, California 94550
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43
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Kim NJ, Paik DH, Zewail AH. Femtosecond dynamics of solvated oxygen anions. II. Nature of dissociation and caging in finite-sized clusters. J Chem Phys 2003. [DOI: 10.1063/1.1561434] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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44
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El Firdoussi A, Esseffar M, Bouab W, Lamsabhi A, Abboud JLM, Mó O, Yáñez M. Basicity of lactones and cyclic ketones towards I2and ICl. An experimental and theoretical study. NEW J CHEM 2003. [DOI: 10.1039/b305387n] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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45
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Himmel HJ, Downs AJ, Greene TM. Reactions of ground state and electronically excited atoms of main group elements: a matrix perspective. Chem Rev 2002; 102:4191-241. [PMID: 12428988 DOI: 10.1021/cr020405x] [Citation(s) in RCA: 129] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Hans-Jörg Himmel
- Institut für Anorganische Chemie, Universität Karlsruhe, Engesserstrasse, Geb 30.45, 76128 Karlsruhe, Germany.
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46
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DeBoer G, Preszler Prince A, Young MA. Charge-transfer mediated photochemistry in alkene–O2 complexes. J Chem Phys 2001. [DOI: 10.1063/1.1386784] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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47
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Paik DH, Bernhardt TM, Kim NJ, Zewail AH. Femtochemistry of mass-selected negative-ion clusters of dioxygen: Charge-transfer and solvation dynamics. J Chem Phys 2001. [DOI: 10.1063/1.1384549] [Citation(s) in RCA: 21] [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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48
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Ananthavel S, Manoharan M. A theoretical study on electron donor–acceptor complexes of Et2O, Et2S and Me3N with interhalogens, I–X (X=Cl and Br). Chem Phys 2001. [DOI: 10.1016/s0301-0104(01)00363-9] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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49
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Resch K, Blanchet V, Stolow A, Seideman T. Toward Polyatomic Wave Packet Decomposition: Final State Effects. J Phys Chem A 2001. [DOI: 10.1021/jp003666o] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Kevin Resch
- Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, Ontario, Canada K1A 0R6
| | - Valérie Blanchet
- Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, Ontario, Canada K1A 0R6
| | - Albert Stolow
- Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, Ontario, Canada K1A 0R6
| | - Tamar Seideman
- Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, Ontario, Canada K1A 0R6
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50
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Rasmusson M, Åkesson E, Eberson L, Sundström V. Ultrafast Formation of Trinitromethanide (C(NO2)3-) by Photoinduced Dissociative Electron Transfer and Subsequent Ion Pair Coupling Reaction in Acetonitrile and Dichloromethane. J Phys Chem B 2001. [DOI: 10.1021/jp002544t] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Marcus Rasmusson
- Department of Chemical Physics, Lunds Universitet, Box 124, 221 00 Lund, Sweden
| | - Eva Åkesson
- Department of Chemical Physics, Lunds Universitet, Box 124, 221 00 Lund, Sweden
| | - Lennart Eberson
- Department of Chemical Physics, Lunds Universitet, Box 124, 221 00 Lund, Sweden
| | - Villy Sundström
- Department of Chemical Physics, Lunds Universitet, Box 124, 221 00 Lund, Sweden
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