1
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Lan J, Chergui M, Pasquarello A. Dynamics of the charge transfer to solvent process in aqueous iodide. Nat Commun 2024; 15:2544. [PMID: 38514610 DOI: 10.1038/s41467-024-46772-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Accepted: 03/05/2024] [Indexed: 03/23/2024] Open
Abstract
Charge-transfer-to-solvent states in aqueous halides are ideal systems for studying the electron-transfer dynamics to the solvent involving a complex interplay between electronic excitation and solvent polarization. Despite extensive experimental investigations, a full picture of the charge-transfer-to-solvent dynamics has remained elusive. Here, we visualise the intricate interplay between the dynamics of the electron and the solvent polarization occurring in this process. Through the combined use of ab initio molecular dynamics and machine learning methods, we investigate the structure, dynamics and free energy as the excited electron evolves through the charge-transfer-to-solvent process, which we characterize as a sequence of states denoted charge-transfer-to-solvent, contact-pair, solvent-separated, and hydrated electron states, depending on the distance between the iodine and the excited electron. Our assignment of the charge-transfer-to-solvent states is supported by the good agreement between calculated and measured vertical binding energies. Our results reveal the charge transfer process in terms of the underlying atomic processes and mechanisms.
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Affiliation(s)
- Jinggang Lan
- Chaire de Simulation à l'Echelle Atomique (CSEA), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland.
- Department of Chemistry, New York University, New York, NY, 10003, USA.
- Simons Center for Computational Physical Chemistry at New York University, New York, NY, 10003, USA.
| | - Majed Chergui
- Lausanne Centre for Ultrafast Science (LACUS), ISIC, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland
- Elettra - Sincrotrone Trieste, Area Science Park I - 34149, Trieste, Italy
| | - Alfredo Pasquarello
- Chaire de Simulation à l'Echelle Atomique (CSEA), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland
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2
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Wang X, Hasan M, Fan L, Wang Y, Li H, Slaughter DS, Centurion M. Mass-selected ion-molecule cluster beam apparatus for ultrafast photofragmentation studies. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2023; 94:095111. [PMID: 37724931 DOI: 10.1063/5.0148194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Accepted: 08/31/2023] [Indexed: 09/21/2023]
Abstract
We describe an apparatus for investigating the excited-state dissociation dynamics of mass-selected ion-molecule clusters by mass-resolving and detecting photofragment-ions and neutrals, in coincidence, using an ultrafast laser operating at high repetition rates. The apparatus comprises a source that generates ion-molecule clusters, a time-of-flight spectrometer, and a mass filter that selects the desired anions, and a linear-plus-quadratic reflectron mass spectrometer that discriminates the fragment anions after the femtosecond laser excites the clusters. The fragment neutrals and anions are then captured by two channeltron detectors. The apparatus performance is tested by measuring the photofragments: I-, CF3I-, and neutrals from photoexcitation of the ion-molecule cluster CF3I·I- using femtosecond UV laser pulses with a wavelength of 266 nm. The experimental results are compared with our ground state and excited state electronic structure calculations as well as the existing results and calculations, with particular attention to the generation mechanism of the anion fragments and dissociation channels of the ion-molecule cluster CF3I·I- in the charge-transfer excited state.
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Affiliation(s)
- Xiaojun Wang
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
| | - Mahmudul Hasan
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
| | - Lin Fan
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
| | - Yibo Wang
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
| | - Hui Li
- Department of Chemistry, Nebraska Center for Materials and Nanoscience, and Center for Integrated Biomolecular Communication, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
| | - Daniel S Slaughter
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd., Berkeley, California 94720, USA
| | - Martin Centurion
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
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3
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Miao L, Liu Z, Chen Z, Wang X, Zhou Z, Zhao J, Fang S, Yin G, Jia Z, Liu J, Moro R, deHeer WA, Ma L. Fourth generation cryogenic neutral cluster beam apparatus for studying fundamental properties of metallic clusters. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2022; 93:113310. [PMID: 36461426 DOI: 10.1063/5.0087524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 10/13/2022] [Indexed: 06/17/2023]
Abstract
A cryogenic beam apparatus for studying neutral clusters has been built and tested. The lowest beam temperature reaches less than 9 K at a repetition rate of 20 Hz. Mechanical decoupling from the refrigerator avoids misalignment during temperature ramping. Adopting a permanent magnet based magnetic deflector eliminates the hysteresis and electric noise of the traditional electromagnet and offers excellent reproducibility of the applied magnetic field. The mass spectrometer can operate in either Mass Spectroscopy Time-Of-Flight mode or Position-Sensitive Time-Of-Flight mode with spatial resolution better than 7 μm. Its performance is demonstrated with niobium and cobalt clusters.
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Affiliation(s)
- Lin Miao
- Tianjin International Center for Nanoparticles and Nanosystems, Tianjin University, 92 Weijin Road, Nankai District, Tianjin 300072, China
| | - Zhaojun Liu
- Tianjin International Center for Nanoparticles and Nanosystems, Tianjin University, 92 Weijin Road, Nankai District, Tianjin 300072, China
| | - Zeyang Chen
- Tianjin International Center for Nanoparticles and Nanosystems, Tianjin University, 92 Weijin Road, Nankai District, Tianjin 300072, China
| | - Xiaohan Wang
- Tianjin International Center for Nanoparticles and Nanosystems, Tianjin University, 92 Weijin Road, Nankai District, Tianjin 300072, China
| | - Ziwen Zhou
- Tianjin International Center for Nanoparticles and Nanosystems, Tianjin University, 92 Weijin Road, Nankai District, Tianjin 300072, China
| | - Jinbo Zhao
- Tianjin International Center for Nanoparticles and Nanosystems, Tianjin University, 92 Weijin Road, Nankai District, Tianjin 300072, China
| | - Shaozheng Fang
- Tianjin International Center for Nanoparticles and Nanosystems, Tianjin University, 92 Weijin Road, Nankai District, Tianjin 300072, China
| | - Guangjia Yin
- Tianjin International Center for Nanoparticles and Nanosystems, Tianjin University, 92 Weijin Road, Nankai District, Tianjin 300072, China
| | - Zezhao Jia
- Tianjin International Center for Nanoparticles and Nanosystems, Tianjin University, 92 Weijin Road, Nankai District, Tianjin 300072, China
| | - Jin Liu
- Tianjin International Center for Nanoparticles and Nanosystems, Tianjin University, 92 Weijin Road, Nankai District, Tianjin 300072, China
| | - Ramiro Moro
- Tianjin International Center for Nanoparticles and Nanosystems, Tianjin University, 92 Weijin Road, Nankai District, Tianjin 300072, China
| | - Walt A deHeer
- School of Physics, Georgia Institute of Technology, 837 North Ave. NW, Atlanta, Georgia 30332, USA
| | - Lei Ma
- Tianjin International Center for Nanoparticles and Nanosystems, Tianjin University, 92 Weijin Road, Nankai District, Tianjin 300072, China
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4
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Wang Z, Hedse A, Amarotti E, Lenngren N, Žídek K, Zheng K, Zigmantas D, Pullerits T. Beating signals in CdSe quantum dots measured by low-temperature 2D spectroscopy. J Chem Phys 2022; 157:014201. [DOI: 10.1063/5.0089798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Advances in ultrafast spectroscopy can provide access to dynamics involving nontrivial quantum correlations and their evolutions. In coherent 2D spectroscopy, the oscillatory time dependence of a signal is a signature of such quantum dynamics. Here we study such beating signals in electronic coherent 2D spectroscopy of CdSe quantum dots (CdSe QDs) at 77 K. The beating signals are analyzed in terms of their positive and negative Fourier components. We conclude that the beatings originate from coherent LO-phonons of CdSe QDs. No evidence for the quantum dot size dependence of the LO-phonon frequency was identified.
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Affiliation(s)
- Zhengjun Wang
- Division of Chemical Physics, Lund Univeristy, Sweden
| | | | | | | | - Karel Žídek
- TOPTEC Research Center, Institute of Plasma Physics Czech Academy of Sciences, Czech Republic
| | - Kaibo Zheng
- Department of Chemical Physics, Lund University, Sweden
| | | | - Tonu Pullerits
- Department of Chemical Physics, Lund University Faculty of Science, Sweden
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5
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Ye T, Zhang TY, Tian FX, Xu B. The fate and transformation of iodine species in UV irradiation and UV-based advanced oxidation processes. WATER RESEARCH 2021; 206:117755. [PMID: 34695669 DOI: 10.1016/j.watres.2021.117755] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 10/04/2021] [Accepted: 10/08/2021] [Indexed: 06/13/2023]
Abstract
Iodinated disinfection byproducts (I-DBPs) formed in water treatment are of emerging concern due to their high toxicity and the tase-and-odor problems associated with iodinated trihalomethanes (I-THMs). Iodoacetic acid and dichloroiodomethane are currently regulated in Shenzhen, China and the Ministry of Health of the People's Republic of China has also been considering regulating I-DBPs. Iodide (I-), organoiodine compounds (e.g., iodinated X-ray contrast media [ICM]), and iodate (IO3-) are the three common iodine sources in aquatic environment that lead to I-DBP formation. While UV irradiation effectively inactivate a wide range of microorganisms in water, it induces the transformation of these iodine sources, enabling the formation of I-DBPs. This review focuses on the fate and transformation of these iodine sources in UV-based water treatment (i.e., UV irradiation and UV-based advanced oxidation processes [UV-AOPs]) and the formation of I-DBPs in post-disinfection. I- released in UV-based treatments of ICM and can be oxidized in subsequent disinfection to hypoiodous acid (HOI), which reacts with natural organic matter (NOM) to produce I-DBPs. Both UV and UV-AOPs are not able to fully mineralize ICM and completely oxidize the released I- to (except UV/O3). Results reveal that UV and UV-AOPs are adequate for I-DBP degradation but require high UV doses. While the ideal I-DBP mitigation strategy awaits to be developed, understanding their sources and formation pathways aids in informed selections of water treatment processes, empowers water suppliers to meet drinking water standards, and minimizes consumers' exposure to I-DBPs.
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Affiliation(s)
- Tao Ye
- Department of Civil and Environmental Engineering, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA.
| | - Tian-Yang Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Fu-Xiang Tian
- School of Chemical and Environmental Engineering, Shanghai Institute of Technology, Shanghai 201418 China
| | - Bin Xu
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
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6
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Zhang YR, Yuan DF, Qian CH, Wang LS. Observation of a dipole-bound excited state in 4-ethynylphenoxide and comparison with the quadrupole-bound excited state in the isoelectronic 4-cyanophenoxide. J Chem Phys 2021; 155:124305. [PMID: 34598564 DOI: 10.1063/5.0065510] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Negative ions do not possess Rydberg states but can have Rydberg-like nonvalence excited states near the electron detachment threshold, including dipole-bound states (DBSs) and quadrupole-bound states (QBSs). While DBSs have been studied extensively, quadrupole-bound excited states have been more rarely observed. 4-cyanophenoxide (4CP-) was the first anion observed to possess a quadrupole-bound exited state 20 cm-1 below its detachment threshold. Here, we report the observation of a DBS in the isoelectronic 4-ethynylphenoxide anion (4EP-), providing a rare opportunity to compare the behaviors of a dipole-bound and a quadrupole-bound excited state in a pair of very similar anions. Photodetachment spectroscopy (PDS) of cryogenically cooled 4EP- reveals a DBS 76 cm-1 below its detachment threshold. Photoelectron spectroscopy (PES) at 266 nm shows that the electronic structure of 4EP- and 4CP- is nearly identical. The observed vibrational features in both the PDS and PES, as well as autodetachment from the nonvalence excited states, are also found to be similar for both anions. However, resonant two-photon detachment (R2PD) from the bound vibrational ground state is observed to be very different for the DBS in 4EP- and the QBS in 4CP-. The R2PD spectra reveal that decays take place from both the DBS and QBS to the respective anion ground electronic states within the 5 ns detachment laser pulse due to internal conversion followed by intramolecular vibrational redistribution and relaxation, but the decay mechanisms appear to be very different. In the R2PD spectrum of 4EP-, we observe strong threshold electron signals, which are due to detachment, by the second photon, of highly rotationally excited anions resulted from the decay of the DBS. On the other hand, in the R2PD spectrum of 4CP-, we observe well-resolved vibrational peaks due to the three lowest-frequency vibrational modes of 4CP-, which are populated from the decay of the QBS. The different behaviors of the R2PD spectra suggest unexpected differences between the relaxation mechanisms of the dipole-bound and quadrupole-bound excited states.
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Affiliation(s)
- Yue-Rou Zhang
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA
| | - Dao-Fu Yuan
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA
| | - Chen-Hui Qian
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA
| | - Lai-Sheng Wang
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA
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7
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Verlet JRR, Anstöter CS, Bull JN, Rogers JP. Role of Nonvalence States in the Ultrafast Dynamics of Isolated Anions. J Phys Chem A 2020; 124:3507-3519. [PMID: 32233436 PMCID: PMC7212518 DOI: 10.1021/acs.jpca.0c01260] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
Nonvalence states
of neutral molecules (Rydberg states) play important
roles in nonadiabatic dynamics of excited states. In anions, such
nonadiabatic transitions between nonvalence and valence states have
been much less explored even though they are believed to play important
roles in electron capture and excited state dynamics of anions. The
aim of this Feature Article is to provide an overview of recent experimental
observations, based on time-resolved photoelectron imaging, of valence
to nonvalence and nonvalence to valence transitions in anions and
to demonstrate that such dynamics may be commonplace in the excited
state dynamics of molecular anions and cluster anions.
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Affiliation(s)
- Jan R R Verlet
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
| | - Cate S Anstöter
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
| | - James N Bull
- School of Chemistry, Norwich Research Park, University of East Anglia, Norwich NR4 7TJ, United Kingdom
| | - Joshua P Rogers
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
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8
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Svoboda V, Michiels R, LaForge AC, Med J, Stienkemeier F, Slavíček P, Wörner HJ. Real-time observation of water radiolysis and hydrated electron formation induced by extreme-ultraviolet pulses. SCIENCE ADVANCES 2020; 6:eaaz0385. [PMID: 32010776 PMCID: PMC6968931 DOI: 10.1126/sciadv.aaz0385] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Accepted: 11/26/2019] [Indexed: 05/17/2023]
Abstract
The dominant pathway of radiation damage begins with the ionization of water. Thus far, however, the underlying primary processes could not be conclusively elucidated. Here, we directly study the earliest steps of extreme ultraviolet (XUV)-induced water radiolysis through one-photon excitation of large water clusters using time-resolved photoelectron imaging. Results are presented for H2O and D2O clusters using femtosecond pump pulses centered at 133 or 80 nm. In both excitation schemes, hydrogen or proton transfer is observed to yield a prehydrated electron within 30 to 60 fs, followed by its solvation in 0.3 to 1.0 ps and its decay through geminate recombination on a ∼10-ps time scale. These results are interpreted by comparison with detailed multiconfigurational non-adiabatic ab-initio molecular dynamics calculations. Our results provide the first comprehensive picture of the primary steps of radiation chemistry and radiation damage and demonstrate new approaches for their study with unprecedented time resolution.
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Affiliation(s)
- Vít Svoboda
- Laboratory of Physical Chemistry, ETH-Zürich, 8093 Zürich, Switzerland
| | - Rupert Michiels
- Institute of Physics, University of Freiburg, 79104 Freiburg, Germany
| | - Aaron C. LaForge
- Institute of Physics, University of Freiburg, 79104 Freiburg, Germany
| | - Jakub Med
- Department of Physical chemistry, UCT Prague, 16628 Prague, Czech Republic
| | | | - Petr Slavíček
- Department of Physical chemistry, UCT Prague, 16628 Prague, Czech Republic
| | - Hans Jakob Wörner
- Laboratory of Physical Chemistry, ETH-Zürich, 8093 Zürich, Switzerland
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9
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Bull JN, Anstöter CS, Verlet JRR. Ultrafast valence to non-valence excited state dynamics in a common anionic chromophore. Nat Commun 2019; 10:5820. [PMID: 31862884 PMCID: PMC6925192 DOI: 10.1038/s41467-019-13819-6] [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: 10/01/2019] [Accepted: 11/27/2019] [Indexed: 12/19/2022] Open
Abstract
Non-valence states in neutral molecules (Rydberg states) have well-established roles and importance in photochemistry, however, considerably less is known about the role of non-valence states in photo-induced processes in anions. Here, femtosecond time-resolved photoelectron imaging is used to show that photoexcitation of the S1(ππ*) state of the methyl ester of deprotonated para-coumaric acid – a model chromophore for photoactive yellow protein (PYP) – leads to a bifurcation of the excited state wavepacket. One part remains on the S1(ππ*) state forming a twisted intermediate, whilst a second part leads to the formation of a non-valence (dipole-bound) state. Both populations eventually decay independently by vibrational autodetachment. Valence-to-non-valence internal conversion has hitherto not been observed in the intramolecular photophysics of an isolated anion, raising questions into how common such processes might be, given that many anionic chromophores have bright valence states near the detachment threshold. Photoactive biomolecules rely on chromophores whose photochemistry depends on the environment. Here, the excited state dynamics of a model for the anionic biochromophore in photoactive yellow protein is investigated by time-resolved photoelectron spectroscopy showing involvement of a non-valence state, and lack of E-Z isomerisation in the gas phase.
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Affiliation(s)
- James N Bull
- School of Chemistry, Norwich Research Park, University of East Anglia, Norwich, NR4 7TJ, UK
| | - Cate S Anstöter
- Department of Chemistry, Durham University, South Road, Durham, DH1 3LE, UK
| | - Jan R R Verlet
- Department of Chemistry, Durham University, South Road, Durham, DH1 3LE, UK.
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10
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Cheng M, Rivas N, Lim SJ, Pichugin K, Petruk AA, Klinkova A, Smith R, Hopkins WS, Sciaini G. Trapping a Photoelectron behind a Repulsive Coulomb Barrier in Solution. J Phys Chem Lett 2019; 10:5742-5747. [PMID: 31498643 DOI: 10.1021/acs.jpclett.9b01712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Multiply charged anions (MCAs) display unique photophysics and solvent-stabilizing effects. Well-known aqueous species such as SO42- and PO43- experience spontaneous electron detachment or charge-separation fragmentation in the gas phase owing to the strong Coulomb repulsion arising from the excess of negative charge. Thus, anions often present low photodetachment thresholds and the ability to quickly eject electrons into the solvent via charge-transfer-to-solvent (CTTS) states. Here, we report spectroscopic evidence for the existence of a repulsive Coulomb barrier (RCB) that blocks the ejection of "CTTS-like" electrons of the aqueous B12F122- dianion. Our spectroscopic experimental and theoretical studies indicate that despite the exerted Coulomb repulsion by the nascent radical monoanion B12F12-•aq, the photoexcited electron remains about the B12F12-• core. The RCB is an established feature of the potential energy landscape of MCAs in vacuo, which seems to extend to the liquid phase highlighting recent observations about the dielectric behavior of confined water.
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Affiliation(s)
- Meixin Cheng
- Department of Chemistry, and Waterloo Institute for Nanotechnology , University of Waterloo , 200 University Avenue W. , Waterloo , ON N2L 3G1 , Canada
| | - Nicolás Rivas
- Department of Chemistry, and Waterloo Institute for Nanotechnology , University of Waterloo , 200 University Avenue W. , Waterloo , ON N2L 3G1 , Canada
| | - Su Ji Lim
- Department of Chemistry, and Waterloo Institute for Nanotechnology , University of Waterloo , 200 University Avenue W. , Waterloo , ON N2L 3G1 , Canada
| | - Kostyantyn Pichugin
- Department of Chemistry, and Waterloo Institute for Nanotechnology , University of Waterloo , 200 University Avenue W. , Waterloo , ON N2L 3G1 , Canada
| | - Ariel A Petruk
- Department of Chemistry, and Waterloo Institute for Nanotechnology , University of Waterloo , 200 University Avenue W. , Waterloo , ON N2L 3G1 , Canada
| | - Anna Klinkova
- Department of Chemistry, and Waterloo Institute for Nanotechnology , University of Waterloo , 200 University Avenue W. , Waterloo , ON N2L 3G1 , Canada
| | - Rodney Smith
- Department of Chemistry, and Waterloo Institute for Nanotechnology , University of Waterloo , 200 University Avenue W. , Waterloo , ON N2L 3G1 , Canada
| | - W Scott Hopkins
- Department of Chemistry, and Waterloo Institute for Nanotechnology , University of Waterloo , 200 University Avenue W. , Waterloo , ON N2L 3G1 , Canada
| | - Germán Sciaini
- Department of Chemistry, and Waterloo Institute for Nanotechnology , University of Waterloo , 200 University Avenue W. , Waterloo , ON N2L 3G1 , Canada
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11
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Zhu GZ, Cheung LF, Liu Y, Qian CH, Wang LS. Resonant Two-Photon Photoelectron Imaging and Intersystem Crossing from Excited Dipole-Bound States of Cold Anions. J Phys Chem Lett 2019; 10:4339-4344. [PMID: 31314535 DOI: 10.1021/acs.jpclett.9b01743] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
We report the observation of a dipole-bound state (DBS) 659 cm-1 below the electron detachment threshold of cryogenically cooled deprotonated 4,4'-biphenol anion (bPh-) and 19 of its lowest vibrational levels. Resonant two-photon photoelectron imaging (R2P-PEI) via the vibrational levels of the DBS displays a sharp peak with a constant binding energy. This observation indicates vertical detachment from the vibrational levels of the DBS to the corresponding neutral levels with the conservation of the vibrational energy, suggesting that the highly diffuse electron in the DBS has little effect on the neutral core. The R2P-PEI spectra also exhibit two features at lower binding energies, which come from intersystem crossings from the DBS to two lower-lying valence-bound triplet excited states of bPh-. The current study discloses the first R2P-PEI spectra from vibrational excited states of a DBS and direct spectroscopic evidence of transitions from a DBS to valence-bound states of anions.
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Affiliation(s)
- Guo-Zhu Zhu
- Department of Chemistry , Brown University , Providence , Rhode Island 02912 , United States
| | - Ling Fung Cheung
- Department of Chemistry , Brown University , Providence , Rhode Island 02912 , United States
| | - Yuan Liu
- Department of Chemistry , Brown University , Providence , Rhode Island 02912 , United States
| | - Chen-Hui Qian
- Department of Chemistry , Brown University , Providence , Rhode Island 02912 , United States
| | - Lai-Sheng Wang
- Department of Chemistry , Brown University , Providence , Rhode Island 02912 , United States
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12
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Mazarji M, Alvarado-Morales M, Tsapekos P, Nabi-Bidhendi G, Mahmoodi NM, Angelidaki I. Graphene based ZnO nanoparticles to depolymerize lignin-rich residues via UV/iodide process. ENVIRONMENT INTERNATIONAL 2019; 125:172-183. [PMID: 30716577 DOI: 10.1016/j.envint.2018.12.062] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 12/19/2018] [Accepted: 12/29/2018] [Indexed: 06/09/2023]
Abstract
In this work, potassium iodide (KI) and graphene oxide (GO) were utilized to promote the selectivity of photocatalytic process for alkali lignin oxidation over ZnO. Different concertation of GO was added during the microwave synthesis procedure of ZnO, and the characterization results revealed that graphene can shift the conduction band to more reducing potential, resulting to higher production of superoxide anion radicals (O2-) compared to OH. Response Surface Methodology revealed the most suitable interaction among loading of GO, KI and irradiation time on lignin and total phenolic compound (TPC) degradation. Specifically, the optimal conditions (i.e. maximum lignin (52%) and minimum TPC (55%) degradation) were at [KI] = 0.64 mM; GO content into ZnO 1.2 mg/mL; 240 min of irradiation time. The results showed that higher addition of graphene into structure of ZnO could preserve more phenolics from degradation due to less production of OH. Furthermore, the addition of KI at optimized conditions could enhance the selectivity of degradation of lignin and phenolics via producing I radicals and quenching the excess amount of generated OH, respectively. The lower generation of OH at optimized conditions was quantitatively confirmed by a photoluminescence simplified technique. In addition, the effect of the photocatalytic process on substrate's anaerobic degradability was examined in order to evaluate the suitability of the pretreated solution for energy recovery. Indeed, besides the higher TPC concentration, the biogas production of treated straw at optimized conditions was increased by 35% compared to the untreated sample.
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Affiliation(s)
- Mahmoud Mazarji
- Department of Environmental Engineering, Technical University of Denmark, Kgs. Lyngby, DK-2800, Denmark; School of Environment, College of Engineering, University of Tehran, Tehran, Iran
| | - Merlin Alvarado-Morales
- Department of Environmental Engineering, Technical University of Denmark, Kgs. Lyngby, DK-2800, Denmark
| | - Panagiotis Tsapekos
- Department of Environmental Engineering, Technical University of Denmark, Kgs. Lyngby, DK-2800, Denmark
| | | | - Niyaz Mohammad Mahmoodi
- Department of Environmental Research, Institute for Color Science and Technology, Tehran, Iran
| | - Irini Angelidaki
- Department of Environmental Engineering, Technical University of Denmark, Kgs. Lyngby, DK-2800, Denmark.
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13
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Naskar P. Structural and spectroscopic aspects of SCN (-)(H 2O) n clusters and the temperature dependency of the isomers: a parallel tempering based approach. Mol Phys 2019. [DOI: 10.1080/00268976.2018.1528395] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- Pulak Naskar
- Department of Chemistry, University of Calcutta, Kolkata, India
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14
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Koga M, Yoneda Y, Sotome H, Miyasaka H. Ionization dynamics of a phenylenediamine derivative in solutions as revealed by femtosecond simultaneous and stepwise two-photon excitation. Phys Chem Chem Phys 2019; 21:2889-2898. [PMID: 30451254 DOI: 10.1039/c8cp06530f] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Femtosecond transient absorption spectroscopy with off-resonant simultaneous and resonant stepwise two-photon excitation methods were applied to the direct observation of photoionization dynamics of a phenylenediamine derivative in n-hexane, ethanol and acetonitrile solutions. Upon the selective excitation of the solute via the off-resonant two-photon excitation to the energy level almost equivalent with the ionization potential in the gas phase, rapid appearance of the radical cation (within ca. 100-200 fs) was observed in polar and nonpolar solutions. On the other hand, in the case where the excited energy level from the ground state is 0.8 eV lower than the ionization potential in the gas phase, the radical cation appears only in polar solutions in sub-ps to ps time scales, indicating that the photoionization does not occur directly from the highly electronically excited state even in the polar solution. Comparison of the dynamics between ethanol and acetonitrile solutions strongly suggested that the solvation process of the precursor species leading to the ionization took a crucial role in the electron ejection process with lower energy in polar solutions.
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Affiliation(s)
- Masafumi Koga
- Division of Frontier Materials Science and Center for Advanced Interdisciplinary Research, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan.
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15
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Marin TW, Janik I, Bartels DM. Ultraviolet charge-transfer-to-solvent spectroscopy of halide and hydroxide ions in subcritical and supercritical water. Phys Chem Chem Phys 2019; 21:24419-24428. [DOI: 10.1039/c9cp03805a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Exploring charge-transfer-to-solvent excitation of aqueous halide anions by vacuum ultraviolet spectroscopy – new insights up to 380 °C.
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Affiliation(s)
- Timothy W. Marin
- Department of Physical Sciences
- Benedictine University
- Lisle
- USA
- Notre Dame Radiation Laboratory
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16
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Dubosq C, Zanuttini D, Gervais B. RASPT2 Analysis of the F–(H2O)n=1–7 and OH–(H2O)n=1–7 CTTS States. J Phys Chem A 2018; 122:7033-7041. [DOI: 10.1021/acs.jpca.8b04970] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- C. Dubosq
- Normandie University, ENSICAEN, UNICAEN, CEA, CNRS, CIMAP, UMR 6252, BP 5133, F-14070 Caen Cedex 05, France
| | - D. Zanuttini
- Normandie University, ENSICAEN, UNICAEN, CEA, CNRS, CIMAP, UMR 6252, BP 5133, F-14070 Caen Cedex 05, France
| | - B. Gervais
- Normandie University, ENSICAEN, UNICAEN, CEA, CNRS, CIMAP, UMR 6252, BP 5133, F-14070 Caen Cedex 05, France
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17
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Rogers JP, Anstöter CS, Verlet JRR. Evidence of Electron Capture of an Outgoing Photoelectron Wave by a Nonvalence State in (C 6F 6) n. J Phys Chem Lett 2018; 9:2504-2509. [PMID: 29694047 DOI: 10.1021/acs.jpclett.8b00739] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Frequency-resolved photoelectron spectra are presented for (C6F6) n- with n = 1-5 that show that C6F6- is solvated by neutral C6F6 molecules. Direct photodetachment channels of C6F6- are observed for all n, leaving the neutral in the S0 ground state or triplet states, T1 and T2. For n ≥ 2, an additional indirect electron loss channel is observed when the triplet-state channels open. This indirect emission appears to arise from the electron capture of the outgoing photoelectron s-wave by a neutral solvent molecule through an anion nonvalence state. The same process is not observed for the S0 detachment channel because the outgoing electron wave is predominantly a p-wave. Our results show that anion nonvalence states can act as electron-accepting states in cluster environments and can be viewed as precursor states for diffuse states of liquid C6F6.
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Affiliation(s)
- Joshua P Rogers
- Department of Chemistry , Durham University , Durham DH1 3LE , United Kingdom
| | - Cate S Anstöter
- Department of Chemistry , Durham University , Durham DH1 3LE , United Kingdom
| | - Jan R R Verlet
- Department of Chemistry , Durham University , Durham DH1 3LE , United Kingdom
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18
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Ge Q, Mao Y, Head-Gordon M. Energy decomposition analysis for exciplexes using absolutely localized molecular orbitals. J Chem Phys 2018; 148:064105. [DOI: 10.1063/1.5017510] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Qinghui Ge
- Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California at Berkeley, Berkeley, California 94720, USA
- Chemical Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Yuezhi Mao
- Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California at Berkeley, Berkeley, California 94720, USA
| | - Martin Head-Gordon
- Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California at Berkeley, Berkeley, California 94720, USA
- Chemical Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
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19
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Ultrafast dynamics of low-energy electron attachment via a non-valence correlation-bound state. Nat Chem 2018; 10:341-346. [PMID: 29461530 DOI: 10.1038/nchem.2912] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Accepted: 11/15/2017] [Indexed: 11/09/2022]
Abstract
The primary electron-attachment process in electron-driven chemistry represents one of the most fundamental chemical transformations with wide-ranging importance in science and technology. However, the mechanistic detail of the seemingly simple reaction of an electron and a neutral molecule to form an anion remains poorly understood, particularly at very low electron energies. Here, time-resolved photoelectron imaging was used to probe the electron-attachment process to a non-polar molecule using time-resolved methods. An initially populated diffuse non-valence state of the anion that is bound by correlation forces evolves coherently in ∼30 fs into a valence state of the anion. The extreme efficiency with which the correlation-bound state serves as a doorway state for low-energy electron attachment explains a number of electron-driven processes, such as anion formation in the interstellar medium and electron attachment to fullerenes.
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20
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Chai Q, Hu A, Qian Y, Ao X, Liu W, Yang H, Xie YF. A comparison of genotoxicity change in reclaimed wastewater from different disinfection processes. CHEMOSPHERE 2018; 191:335-341. [PMID: 29045934 DOI: 10.1016/j.chemosphere.2017.10.024] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Revised: 10/01/2017] [Accepted: 10/04/2017] [Indexed: 06/07/2023]
Abstract
Effluents before disinfection from four wastewater reclamation plants were treated with chlorine (Cl2), ozone (O3), chlorine dioxide (ClO2), medium-pressure ultraviolet (MPUV) and four different combinations of the above, to evaluate the effect of disinfection processes on the genotoxicity removal by the SOS/umu test. Results showed that the genotoxicity increased after MPUV irradiation (10-100 mJ/cm2), but declined when adopting other disinfection processes. The effectiveness of genotoxicity reduction by five chemical disinfectants was identified as: O3 > pre-ozonation with Cl2 ≈ ClO2 > combination of ClO2 and Cl2 > Cl2. The sequential combination of MPUV, Cl2 and O3 reduced the genotoxicity to a level similar to the source water. The influence of differential disinfection process varied on iodinated wastewater, which is closely related to the competitive reactions between disinfectants, iodine and dissolved organic matters. The removal of genotoxic pollutants and the formation of genotoxic disinfection by-products are the two major factors that lead to the change in genotoxicity during disinfection.
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Affiliation(s)
- Qiwan Chai
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, 100084, China
| | - Allen Hu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, 100084, China
| | - Yukun Qian
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, 100084, China
| | - Xiuwei Ao
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, 100084, China
| | - Wenjun Liu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, 100084, China
| | - Hongwei Yang
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, 100084, China.
| | - Yuefeng F Xie
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, 100084, China; Environmental Engineering Programs, The Pennsylvania State University, Middletown, PA 17057, USA
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21
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Sun Z, Zhang C, Chen P, Zhou Q, Hoffmann MR. Impact of humic acid on the photoreductive degradation of perfluorooctane sulfonate (PFOS) by UV/Iodide process. WATER RESEARCH 2017; 127:50-58. [PMID: 29031799 DOI: 10.1016/j.watres.2017.10.010] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 10/03/2017] [Accepted: 10/05/2017] [Indexed: 06/07/2023]
Abstract
Iodide photolysis under UV illumination affords an effective method to produce hydrated electrons (eaq-) in aqueous solution. Therefore, UV/Iodide photolysis can be utilized for the reductive degradation of many recalcitrant pollutants. However, the effect of naturally occurring organic matter (NOM) such as humic and fulvic acids (HA/FA), which may impact the efficiency of UV/Iodide photoreduction, is poorly understood. In this study, the UV photoreductive degradation of perfluorooctane sulfonate (PFOS) in the presence of I- and HA is studied. PFOS undergoes a relatively slow direct photoreduction in pure water, a moderate level of degradation via UV/Iodide, but a rapid degradation via UV/Iodide/HA photolysis. After 1.5 h of photolysis, 86.0% of the initial [PFOS] was degraded in the presence of both I- and HA with a corresponding defluorination ratio of 55.6%, whereas only 51.7% of PFOS was degraded with a defluorination ratio of 4.4% via UV/Iodide illumination in the absence of HA. The relative enhancement in the presence of HA in the photodegradation of PFOS can be attributed to several factors: a) HA enhances the effective generation of eaq- due to the reduction of I2, HOI, IO3- and I3- back to I-; b) certain functional groups of HA (i.e., quinones) enhance the electron transfer efficiency as electron shuttles; c) a weakly-bonded association of I- and PFOS with HA increases the reaction probability; and d) absorption of UV photons by HA itself produces eaq-. The degradation and defluorination efficiency of PFOS by UV/Iodide/HA process is dependent on pH and HA concentration. As pH increases from 7.0 to 10.0, the enhancement effect of HA improves significantly. The optimal HA concentration for the degradation of 0.03 mM PFOS is 1.0 mg L-1.
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Affiliation(s)
- Zhuyu Sun
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Chaojie Zhang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
| | - Pei Chen
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Qi Zhou
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Michael R Hoffmann
- Linde-Robinson Laboratories, California Institute of Technology, Pasadena, CA 91125, United States
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22
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Mirdha RH, Chaudhury P. Constructing a bunch of paths for conformational changes in size specific noble gas cluster: a study using a stochastic procedure. JOURNAL OF MATHEMATICAL CHEMISTRY 2017; 55:1916-1933. [DOI: 10.1007/s10910-017-0771-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/19/2023]
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23
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Sun Z, Zhang C, Zhao X, Chen J, Zhou Q. Efficient photoreductive decomposition of N-nitrosodimethylamine by UV/iodide process. JOURNAL OF HAZARDOUS MATERIALS 2017; 329:185-192. [PMID: 28171837 DOI: 10.1016/j.jhazmat.2016.12.046] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 12/21/2016] [Accepted: 12/23/2016] [Indexed: 06/06/2023]
Abstract
N-nitrosodimethylamine (NDMA) has aroused extensive concern as a disinfection byproduct due to its high toxicity and elevated concentration levels in water sources. This study investigates the photoreductive decomposition of NDMA by UV/iodide process. The results showed that this process is an effective strategy for the treatment of NDMA with 99.2% NDMA removed within 10min. The depletion of NDMA by UV/iodide process obeyed pseudo-first-order kinetics with a rate constant (k1) of 0.60±0.03min-1. Hydrated electrons (eaq-) generated by the UV irradiation of iodide were proven to play a critical role. Dimethylamine (DMA) and nitrite (NO2-) were formed as the main intermediate products, which completely converted to formate (HCOO-), ammonium (NH4+) and nitrogen (N2). Therefore, not only the high efficiencies in NDMA destruction, but the elimination of toxic intermediates make UV/iodide process advantageous. A photoreduction mechanism was proposed: NDMA initially absorbed photons to a photoexcited state, and underwent a cleavage of NNO bond under the attack of eaq-. The solution pH had little impact on NDMA removal. However, alkaline conditions were more favorable for the elimination of DMA and NO2-, thus effectively reducing the secondary pollution.
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Affiliation(s)
- Zhuyu Sun
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Chaojie Zhang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
| | - Xiaoyun Zhao
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Jing Chen
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Qi Zhou
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
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24
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Berton M, Mello R, González-Núñez ME. Iodide-Photocatalyzed Reduction of Carbon Dioxide to Formic Acid with Thiols and Hydrogen Sulfide. CHEMSUSCHEM 2016; 9:3397-3400. [PMID: 27925406 DOI: 10.1002/cssc.201601285] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Revised: 10/05/2016] [Indexed: 06/06/2023]
Abstract
The photolysis of iodide anions promotes the reaction of carbon dioxide with hydrogen sulfide or thiols to quantitatively yield formic acid and sulfur or disulfides. The reaction proceeds in acetonitrile and aqueous solutions, at atmospheric pressure and room temperature by irradiation using a low-pressure mercury lamp. This transition-metal-free photocatalytic process for CO2 capture coupled with H2 S removal may have been relevant as a prebiotic carbon dioxide fixation.
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Affiliation(s)
- Mateo Berton
- Departamento de Química Orgánica, Universidad de Valencia, Avda. Vicente Andrés Estellés s.n., 46100-, Burjassot, Valencia, Spain
| | - Rossella Mello
- Departamento de Química Orgánica, Universidad de Valencia, Avda. Vicente Andrés Estellés s.n., 46100-, Burjassot, Valencia, Spain
| | - María Elena González-Núñez
- Departamento de Química Orgánica, Universidad de Valencia, Avda. Vicente Andrés Estellés s.n., 46100-, Burjassot, Valencia, Spain
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25
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Wen H, Huang T, Liu YR, Jiang S, Peng XQ, Miao SK, Wang CY, Hong Y, Huang W. Structure, temperature effect and bonding order analysis of hydrated bromide clusters. Chem Phys 2016. [DOI: 10.1016/j.chemphys.2016.09.039] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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26
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Naskar P, Chaudhury P. An investigation on the structure, spectroscopy and thermodynamic aspects of Br2((-))(H2O)n clusters using a conjunction of stochastic and quantum chemical methods. Phys Chem Chem Phys 2016; 18:16245-57. [PMID: 27251059 DOI: 10.1039/c6cp01960a] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this work we obtained global as well as local structures of Br2((-))(H2O)n clusters for n = 2 to 6 followed by the study of IR-spectral features and thermochemistry for the structures. The way adopted by us to obtain structures is not the conventional one used in most cases. Here we at first generated excellent quality pre-optimized structures by exploring the suitable empirical potential energy surface using stochastic optimizer simulated annealing. These structures are then further refined using quantum chemical calculations to obtain the final structures, and spectral and thermodynamic features. We clearly showed that our approach results in very quick and better convergence which reduces the computational cost and obviously using the strategy we are able to get one [i.e. global] or more than one [i.e. global and local(s)] energetically lower structures than those which are already reported for a given cluster size. Moreover, IR-spectral results and the evolutionary trends in interaction energy, solvation energy and vertical detachment energy for global structures of each size have also been presented to establish the utility of the procedure employed.
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Affiliation(s)
- Pulak Naskar
- Department of Chemistry, University of Calcutta, 92 A P C Road, Kolkata 700 009, India.
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27
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King SB, Stephansen AB, Yokoi Y, Yandell MA, Kunin A, Takayanagi T, Neumark DM. Electron accommodation dynamics in the DNA base thymine. J Chem Phys 2016; 143:024312. [PMID: 26178110 DOI: 10.1063/1.4923343] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The dynamics of electron attachment to the DNA base thymine are investigated using femtosecond time-resolved photoelectron imaging of the gas phase iodide-thymine (I(-)T) complex. An ultraviolet pump pulse ejects an electron from the iodide and prepares an iodine-thymine temporary negative ion that is photodetached with a near-IR probe pulse. The resulting photoelectrons are analyzed with velocity-map imaging. At excitation energies ranging from -120 meV to +90 meV with respect to the vertical detachment energy (VDE) of 4.05 eV for I(-)T, both the dipole-bound and valence-bound negative ions of thymine are observed. A slightly longer rise time for the valence-bound state than the dipole-bound state suggests that some of the dipole-bound anions convert to valence-bound species. No evidence is seen for a dipole-bound anion of thymine at higher excitation energies, in the range of 0.6 eV above the I(-)T VDE, which suggests that if the dipole-bound anion acts as a "doorway" to the valence-bound anion, it only does so at excitation energies near the VDE of the complex.
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Affiliation(s)
- Sarah B King
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Anne B Stephansen
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 København Ø, Denmark
| | - Yuki Yokoi
- Department of Chemistry, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama City, Saitama 338-8570, Japan
| | - Margaret A Yandell
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Alice Kunin
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Toshiyuki Takayanagi
- Department of Chemistry, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama City, Saitama 338-8570, Japan
| | - Daniel M Neumark
- Department of Chemistry, University of California, Berkeley, California 94720, USA
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28
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Guo Y, Ding Z, Sun L, Li J, Meng S, Lu X. Inducing Transient Charge State of a Single Water Cluster on Cu(111) Surface. ACS NANO 2016; 10:4489-4495. [PMID: 27007702 DOI: 10.1021/acsnano.6b00230] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The hydrated electron on solid surface is a crucial species to interfacial chemistry. We present a joint low-temperature scanning tunneling microscopy and density functional theory investigation to explore the existence of a transient hydrated electron state induced by injecting tunneling electrons into a single water nonamer cluster on Cu(111) surface. The directional diffusion of water cluster under the Coulomb repulsive potential has been observed as evidence for the emergence of the transient hydrated electron. A critical structure transformation in water cluster for the emergence of hydrated electron has been identified. A charging mechanism has been proposed based on density functional theory calculation and scanning tunneling microscope results.
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Affiliation(s)
- Yang Guo
- Beijing National Laboratory for Condensed-Matter Physics and Institute of Physics, Chinese Academy of Sciences , Beijing 100190, People's Republic of China
| | - Zijing Ding
- Beijing National Laboratory for Condensed-Matter Physics and Institute of Physics, Chinese Academy of Sciences , Beijing 100190, People's Republic of China
| | - Lihuan Sun
- Beijing National Laboratory for Condensed-Matter Physics and Institute of Physics, Chinese Academy of Sciences , Beijing 100190, People's Republic of China
| | - Jianmei Li
- Beijing National Laboratory for Condensed-Matter Physics and Institute of Physics, Chinese Academy of Sciences , Beijing 100190, People's Republic of China
| | - Sheng Meng
- Beijing National Laboratory for Condensed-Matter Physics and Institute of Physics, Chinese Academy of Sciences , Beijing 100190, People's Republic of China
- Collaborative Innovation Center of Quantum Matter , Beijing 100190, People's Republic of China
| | - Xinghua Lu
- Beijing National Laboratory for Condensed-Matter Physics and Institute of Physics, Chinese Academy of Sciences , Beijing 100190, People's Republic of China
- Collaborative Innovation Center of Quantum Matter , Beijing 100190, People's Republic of China
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29
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Naskar P, Chaudhury P. Structural and spectroscopic studies of iodine dimer radical anion hydrated clusters: an approach using a combination of stochastic and quantum chemical methods. RSC Adv 2016. [DOI: 10.1039/c5ra19763e] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Structures of I2(−)(H2O)5 clusters after evaluation by simulated annealing and subsequent DFT calculation respectively.
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Affiliation(s)
- Pulak Naskar
- Department of Chemistry
- University of Calcutta
- Kolkata 700 009
- India
| | - Pinaki Chaudhury
- Department of Chemistry
- University of Calcutta
- Kolkata 700 009
- India
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30
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31
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Heine N, Asmis KR. Cryogenic ion trap vibrational spectroscopy of hydrogen-bonded clusters relevant to atmospheric chemistry. INT REV PHYS CHEM 2014. [DOI: 10.1080/0144235x.2014.979659] [Citation(s) in RCA: 115] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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32
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Mak CC, Peslherbe GH. New developments in first-principles excited-state dynamics simulations: unveiling the solvent specificity of excited anionic cluster relaxation and electron solvation. MOLECULAR SIMULATION 2014. [DOI: 10.1080/08927022.2014.945083] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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33
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Mak CC, Peslherbe GH. Relaxation Pathways of Photoexcited Iodide–Methanol Clusters: A Computational Investigation. J Phys Chem A 2014; 118:4494-501. [DOI: 10.1021/jp503216m] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Chun C. Mak
- Centre for Research in Molecular
Modeling and Department of Chemistry and Biochemistry, Concordia University, Montréal, Québec H4B 1R6, Canada
| | - Gilles H. Peslherbe
- Centre for Research in Molecular
Modeling and Department of Chemistry and Biochemistry, Concordia University, Montréal, Québec H4B 1R6, Canada
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34
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Sheu WS, Chiou MF. Effects of Iodine on the Relaxation Dynamics of a Photoexcited I–(H2O)4 Cluster. J Phys Chem A 2013; 117:13946-53. [DOI: 10.1021/jp406108r] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Wen-Shyan Sheu
- Department
of Chemistry, Fu-Jen Catholic University, Xinzhuang, New Taipei City 24205, Taiwan, ROC
| | - Mong-Feng Chiou
- Department
of Chemistry, Fu-Jen Catholic University, Xinzhuang, New Taipei City 24205, Taiwan, ROC
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35
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Allolio C, Salas-Illanes N, Desmukh YS, Hansen MR, Sebastiani D. H-Bonding Competition and Clustering in Aqueous LiI. J Phys Chem B 2013; 117:9939-46. [DOI: 10.1021/jp4033468] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Christoph Allolio
- Department of Chemistry, Martin-Luther Universität Halle-Wittenberg, von-Danckelmann-Platz
4, 06120 Halle/Saale, Germany
| | - Nora Salas-Illanes
- Department of Chemistry, Martin-Luther Universität Halle-Wittenberg, von-Danckelmann-Platz
4, 06120 Halle/Saale, Germany
| | - Yogesh S. Desmukh
- Department of Chemical
Engineering and Chemistry, Eindhoven University of Technology, P.O. Box 513, Eindhoven, Netherlands
- Dutch Polymer Institute (DPI), P.O. Box 902, 5600AX Eindhoven, The Netherlands
| | - Michael Ryan Hansen
- Dutch Polymer Institute (DPI), P.O. Box 902, 5600AX Eindhoven, The Netherlands
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz,
Germany
| | - Daniel Sebastiani
- Department of Chemistry, Martin-Luther Universität Halle-Wittenberg, von-Danckelmann-Platz
4, 06120 Halle/Saale, Germany
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36
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Mak CC, Timerghazin QK, Peslherbe GH. Photoexcitation and Charge-Transfer-to-Solvent Relaxation Dynamics of the I–(CH3CN) Complex. J Phys Chem A 2013; 117:7595-605. [DOI: 10.1021/jp403586u] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Chun C. Mak
- Centre for
Research in Molecular Modeling (CERMM) and
Department of Chemistry and Biochemistry, Concordia University, 7141 Sherbrooke Street West, Montréal, Québec, Canada
H4B 1R6
| | - Qadir K. Timerghazin
- Centre for
Research in Molecular Modeling (CERMM) and
Department of Chemistry and Biochemistry, Concordia University, 7141 Sherbrooke Street West, Montréal, Québec, Canada
H4B 1R6
| | - Gilles H. Peslherbe
- Centre for
Research in Molecular Modeling (CERMM) and
Department of Chemistry and Biochemistry, Concordia University, 7141 Sherbrooke Street West, Montréal, Québec, Canada
H4B 1R6
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37
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Qiu Y, Yang M, Chen W, Su Y, Ouyang Z, Yan H, Gao F, Dong W. Crystal structures, UV spectra of solid iodide anionic water clusters I(-)(H2O)(1-4), and electrochemical reaction of I(-)(H2O)(1-4) → I· + e(-)(H2O)(1-4). J Phys Chem A 2013; 117:4051-6. [PMID: 23614806 DOI: 10.1021/jp402279k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Four iodide anionic water clusters of I(-)(H2O)1-4 in two supramolecular complexes of [Fe(phen)3][I2(H2O)3] (1) and [Zn(phen)3][I2(H2O)4.5] (2) have been determined by single-crystal X-ray diffraction analysis. The diffuse reflectance spectra for the solid iodide anionic water clusters of I(-)(H2O)1-4 were investigated, and their absorption bands were demonstrated by denisty functional theory calculation. The electrochemical reaction of I(-)(H2O)1-4 → I· + e(-)(H2O)1-4 with the oxidation potential of Ep = 0.61 eV was first found and reported in two aqueous solutions (1 mmol·dm(-3)) of 1 and 2.
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Affiliation(s)
- Yanxuan Qiu
- Department of Chemistry, Guangzhou Key Laboratory for Environmentally Functional Materials and Technology, Guangzhou University, Guangzhou 510006, PR China
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38
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Zhang M, Zhao J, Liu J, Zhou L, Bu Y. Coexistence of solvated electron and benzene-centered valence anion in the negatively charged benzene-water clusters. J Chem Phys 2013; 138:014310. [PMID: 23298044 DOI: 10.1063/1.4773398] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We present a combined M06 functional calculation and ab initio molecular dynamics simulation study of an excess electron (EE) in a microhydrated aromatic complex (modeled by benzene (Bz)-water binary clusters, Bz(H(2)O)(n)). Calculated results illustrate that Bz ring and water clusters are indeed linked through the π···HO interactions in the neutral Bz(H(2)O)(n) (n = 1-8) clusters, and the size of the water cluster does not influence the nature of its interaction with the π system for the oligo-hydrated complexes. The states and the dynamics of an EE trapped in such Bz-water clusters were also determined. All of possible localized states for the EE can be roughly classified into two types: (i) single, ring-localized states (the Bz-centered valence anions) in which an EE occupies the LUMO of the complexes originating from the LUMO (π*) of the Bz ring, and the π···HO interactions are enhanced for increase of electron density of the Bz ring. In this mode, the carbon skeleton of the Bz part is significantly deformed due to increase of electron density and nonsymmetric distribution of electron density induced by the interacting H-O bonds; (ii) solvated states, in which an EE is trapped directly as a surface state by the dangling hydrogen atoms of water molecules or as a solvated state in a mixed cavity formed by Bz and water cluster. In the latter case, Bz may also participate in capturing an EE using its C-H bonds in the side edge of the aromatic ring as a part of the cavity. In general, a small water cluster is favorable to the Bz-centered valence anion state, while a large one prefers a solvated electron state. Fluctuations and rearrangement of water molecules can sufficiently modify the relative energies of the EE states to permit facile conversion from the Bz-centered to the water cluster-centered state. This indicates that aromatic Bz can be identified as a stepping stone in electron transfer and the weak π···HO interaction plays an important role as the driving force in conversion of the two states.
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Affiliation(s)
- Meng Zhang
- The Center for Modeling and Simulation Chemistry, Institute of Theoretical Chemistry, Shandong University, Jinan 250100, People's Republic of China
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39
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Penfold T, Tavernelli I, Doemer M, Abela R, Röthlisberger U, Chergui M. Solvent rearrangements during the transition from hydrophilic to hydrophobic solvation. Chem Phys 2013. [DOI: 10.1016/j.chemphys.2012.10.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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40
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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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41
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Affiliation(s)
- Ryan M. Young
- Department of Chemistry, University of California, Berkeley, California 94720,
United States
| | - Daniel M. Neumark
- Department of Chemistry, University of California, Berkeley, California 94720,
United States
- Chemical
Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California
94720, United States
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42
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Alizadeh E, Sanche L. Precursors of solvated electrons in radiobiological physics and chemistry. Chem Rev 2012; 112:5578-602. [PMID: 22724633 DOI: 10.1021/cr300063r] [Citation(s) in RCA: 225] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Elahe Alizadeh
- Groupe en Sciences des Radiations, Département de Médecine Nucléaire et Radiobiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Canada
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43
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Wang QQ, Day VW, Bowman-James K. Supramolecular Encapsulation of Tetrahedrally Hydrated Guests in a Tetrahedron Host. Angew Chem Int Ed Engl 2012; 51:2119-23. [DOI: 10.1002/anie.201106090] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2011] [Revised: 11/28/2011] [Indexed: 11/12/2022]
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44
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Wang QQ, Day VW, Bowman-James K. Supramolecular Encapsulation of Tetrahedrally Hydrated Guests in a Tetrahedron Host. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201106090] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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45
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Ji M, Hartsock RW, Sung Z, Gaffney KJ. Influence of solute-solvent coordination on the orientational relaxation of ion assemblies in polar solvents. J Chem Phys 2012; 136:014501. [DOI: 10.1063/1.3665140] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
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46
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Mak CC, Timerghazin QK, Peslherbe GH. Photoinduced electron transfer and solvation dynamics in aqueous clusters: comparison of the photoexcited iodide-water pentamer and the water pentamer anion. Phys Chem Chem Phys 2012; 14:6257-65. [DOI: 10.1039/c2cp24099h] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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47
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Willow SY, Singh NJ, Kim KS. NH4+ Resides Inside the Water 20-mer Cage As Opposed to H3O+, Which Resides on the Surface: A First Principles Molecular Dynamics Simulation Study. J Chem Theory Comput 2011; 7:3461-5. [DOI: 10.1021/ct200486c] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Soohaeng Yoo Willow
- Center for Superfunctional Materials, Department of Chemistry, Pohang University of Science and Technology, San 31, Hyojadong, Namgu, Pohang 790-784, Korea
| | - N. Jiten Singh
- Center for Superfunctional Materials, Department of Chemistry, Pohang University of Science and Technology, San 31, Hyojadong, Namgu, Pohang 790-784, Korea
| | - Kwang S. Kim
- Center for Superfunctional Materials, Department of Chemistry, Pohang University of Science and Technology, San 31, Hyojadong, Namgu, Pohang 790-784, Korea
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48
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Pathak AK. Connecting finite size charge-transfer-to-solvent energy to the bulk: A general microscopic theory. Chem Phys Lett 2011. [DOI: 10.1016/j.cplett.2011.07.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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49
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50
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Lin M, Archirel P, Van-Oanh NT, Muroya Y, Fu H, Yan Y, Nagaishi R, Kumagai Y, Katsumura Y, Mostafavi M. Temperature Dependent Absorption Spectra of Br−, Br2•−, and Br3− in Aqueous Solutions. J Phys Chem A 2011; 115:4241-7. [DOI: 10.1021/jp1123103] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Mingzhang Lin
- Nuclear Engineering and Science Directorate, Japan Atomic Energy Agency, 2-4 Shirakata shirane, Tokaimura, Nakagun, Ibaraki 319-1195, Japan
| | - Pierre Archirel
- Laboratoire de Chimie Physique/ELYSE, Université Paris-Sud 11, UMR 8000, Bâtiment 349, Orsay, 91405 France
| | - Nguyen Thi Van-Oanh
- Laboratoire de Chimie Physique/ELYSE, Université Paris-Sud 11, UMR 8000, Bâtiment 349, Orsay, 91405 France
| | | | | | | | - Ryuji Nagaishi
- Nuclear Engineering and Science Directorate, Japan Atomic Energy Agency, 2-4 Shirakata shirane, Tokaimura, Nakagun, Ibaraki 319-1195, Japan
| | - Yuta Kumagai
- Nuclear Engineering and Science Directorate, Japan Atomic Energy Agency, 2-4 Shirakata shirane, Tokaimura, Nakagun, Ibaraki 319-1195, Japan
| | | | - Mehran Mostafavi
- Laboratoire de Chimie Physique/ELYSE, Université Paris-Sud 11, UMR 8000, Bâtiment 349, Orsay, 91405 France
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