1
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Lu F, Kitanosono T, Yamashita Y, Kobayashi S. Small-Molecule-Based Strategy for Mitigating Deactivation of Chiral Lewis Acid Catalysis. J Am Chem Soc 2024; 146:22918-22922. [PMID: 39106440 DOI: 10.1021/jacs.4c07449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/09/2024]
Abstract
Chiral Lewis acid catalysts are widely used in organic synthesis due to their diverse applications. However, their high Lewis acidity makes them susceptible to deactivation by basic Lewis reagents and water. Here, we present a novel strategy for mitigating this deactivation using small molecules. By incorporating weakly coordinating anions into the secondary coordination sphere of the metal center, we designed a highly reusable chiral Lewis acid complex. This complex exhibits excellent thermal stability and allows for the use of electron-poor nucleophiles in the reactions. Spectroscopic and titration studies confirmed the robustness of the optimized complex. This work provides valuable insights for overcoming the limitations of chiral Lewis acids in Lewis basic environments, expanding their potential for chemical synthesis.
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Affiliation(s)
- Fangqiu Lu
- Department of Chemistry, School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Taku Kitanosono
- Department of Chemistry, School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Yasuhiro Yamashita
- Department of Chemistry, School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Shu Kobayashi
- Department of Chemistry, School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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2
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Pajoubpong J, Mayhan CM, Dar AA, Greenwood AI, Klebba KC, Cremer ML, Kumari H. Dynamic macromolecular material design: the versatility of cucurbituril over cyclodextrin in host-guest chemistry. NANOSCALE ADVANCES 2024; 6:4376-4384. [PMID: 39170981 PMCID: PMC11334980 DOI: 10.1039/d4na00324a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/17/2024] [Accepted: 06/26/2024] [Indexed: 08/23/2024]
Abstract
The keto-enol tautomerism of avobenzone (AVO) is pivotal to its photostability, influenced by microenvironmental factors, such as, the type of solvent and complexation with macrocyclic compounds. This study explores the effect of host-guest complexation on AVO photostabilization, employing cucurbit[7]uril (CB[7]) and β-cyclodextrin (β-CD) to form inclusion complexes. CB[7] exhibits a higher affinity to the keto form of AVO, a UVC radiation absorber. The complexed keto form facilitates the regeneration of the enol form, reducing skin permeation. Spectroscopic and thermal analyses confirm 1 : 1 AVO-CB[7] and AVO-β-CD complex formation. Computational and MD simulations show that host-guest complex is favored over isolated AVO and β-CD or CB[7] molecules by 95-125 kJ mol-1, depending on the presence of implicit solvent. Both macrocycles enhance AVO photostabilization in aqueous environments, with CB[7] displaying greater selectivity for the keto form, while β-CD shows ethanol concentration-dependent binding.
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Affiliation(s)
- Jinnipha Pajoubpong
- James L. Winkle College of Pharmacy, University of Cincinnati 231 Albert Sabin Way Cincinnati OH 45267-0514 USA
| | - Collin M Mayhan
- James L. Winkle College of Pharmacy, University of Cincinnati 231 Albert Sabin Way Cincinnati OH 45267-0514 USA
- Helias Catholic High School 1305 Swifts Hwy Jefferson City MO 65109 USA
| | - Ajaz Ahmad Dar
- James L. Winkle College of Pharmacy, University of Cincinnati 231 Albert Sabin Way Cincinnati OH 45267-0514 USA
| | | | - Karoline C Klebba
- Helias Catholic High School 1305 Swifts Hwy Jefferson City MO 65109 USA
| | - Matthew L Cremer
- Helias Catholic High School 1305 Swifts Hwy Jefferson City MO 65109 USA
| | - Harshita Kumari
- James L. Winkle College of Pharmacy, University of Cincinnati 231 Albert Sabin Way Cincinnati OH 45267-0514 USA
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3
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Verduci R, Creazzo F, Tavella F, Abate S, Ampelli C, Luber S, Perathoner S, Cassone G, Centi G, D'Angelo G. Water Structure in the First Layers on TiO 2: A Key Factor for Boosting Solar-Driven Water-Splitting Performances. J Am Chem Soc 2024; 146:18061-18073. [PMID: 38909313 DOI: 10.1021/jacs.4c05042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/24/2024]
Abstract
The water hydrogen-bonded network is strongly perturbed in the first layers in contact with the semiconductor surface. Even though this aspect influences the outer-sphere electron transfer, it was not recognized that it is a crucial factor impacting the solar-driven water-splitting performances. To fill this gap, we have selected two TiO2 anatase samples (with and without B-doping), and by extensive experimental and computational investigations, we have demonstrated that the remarkable 5-fold increase in water-splitting photoactivity of the B-doped sample cannot be ascribed to effects typically associated to enhanced photocatalytic properties, such as band gap, heterojunctions, crystal facets, and other aspects. Studying these samples by combining FTIR measurements under controlled humidity with first-principles simulations sheds light on the role and nature of the first-layer water structure in contact with the photocatalyst surfaces. It turns out that the doping hampers the percolation of tetrahedrally coordinated water molecules while enhancing the population of topological H-bond defects forming approximately linear H-bonded chains. This work unveils how doping the semiconductor surface affects the local electric field, determining the water splitting rate by influencing the H-bond topologies in the first water layers. This evidence opens new prospects for designing efficient photocatalysts for water splitting.
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Affiliation(s)
- Rosaria Verduci
- Department of Mathematical and Computational Sciences, Physical Science and Earth Science (MIFT), University of Messina, V.le F. Stagno d'Alcontres 31, 98166 Messina, Italy
| | - Fabrizio Creazzo
- Department of Chemistry, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
| | - Francesco Tavella
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences (ChiBioFarAm), University of Messina, ERIC aisbl and CASPE/INSTM, 98166 Messina, Italy
| | - Salvatore Abate
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences (ChiBioFarAm), University of Messina, ERIC aisbl and CASPE/INSTM, 98166 Messina, Italy
| | - Claudio Ampelli
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences (ChiBioFarAm), University of Messina, ERIC aisbl and CASPE/INSTM, 98166 Messina, Italy
| | - Sandra Luber
- Department of Chemistry, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
| | - Siglinda Perathoner
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences (ChiBioFarAm), University of Messina, ERIC aisbl and CASPE/INSTM, 98166 Messina, Italy
| | - Giuseppe Cassone
- Institute for Chemical-Physical Processes, National Research Council of Italy (IPCF-CNR), Viale F. Stagno d'Alcontres 37, 98158 Messina, Italy
| | - Gabriele Centi
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences (ChiBioFarAm), University of Messina, ERIC aisbl and CASPE/INSTM, 98166 Messina, Italy
| | - Giovanna D'Angelo
- Department of Mathematical and Computational Sciences, Physical Science and Earth Science (MIFT), University of Messina, V.le F. Stagno d'Alcontres 31, 98166 Messina, Italy
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4
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Dong H, Feng Y, Bu Y. Electron Presolvation in Tetrahydrofuran-Incorporated Supramolecular Sodium Entities. J Phys Chem A 2023; 127:1402-1412. [PMID: 36748233 DOI: 10.1021/acs.jpca.2c06944] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Alkali metal atoms can repopulate their valence electrons toward solvation due to impact from solvents or microsurroundings and provide the remaining alkali metal cations for coordinating with a variety of specific solvents, forming various electron-expanded complexes or solvated ionic pairs with special interactions. Such special solute-solvent interactions not only affect their electronic structures but also enable the formation of entirely new species. Taking Na(THF)n (n = 1-6, THF = tetrahydrofuran) and Na2@THF complexes as typical representatives, density functional theory calculations are carried out to explore the solvation of a sodium atom and its dimer in THF and characterize their complexes as solvent-incorporated supramolecular entities and particularly valence electron presolvation due to their interaction with solvent THF. Electron presolvation is caused by the Pauli repulsion between THF containing a coordinating O atom with a lone pair of electrons and the alkali metal Na or Na2 containing valence electrons, and THF coordination to them forces their valence electrons to redistribute, which can be easily realized in such solvents. Compared with strongly bound valance electrons of alkali metal atoms, THF coordination enables Na or Na2 electrons to exhibit much more active states (i.e., the presolvated states) featuring small vertical detachment energies of electrons and distorted diffuse distributions in the frames of the generally structured metal cation complexes, acting as the electron-expanded chemical entities. Furthermore, the degree of electron diffusion and the polarity of the Na-Na bond are proportional to the coordination number (n) and the coordination number difference (Δn) between two Na centers in Na2@THF. The unique properties of such entities are also discussed. This work offers a theoretical support to the supramolecular entities formed by alkali-metal atoms or their dimers with ligands containing O or N and uncovers the unique electron presolvation phenomena and also enriches our understanding of the novel metal atom complexes.
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Affiliation(s)
- Hui Dong
- School of Chemistry and Chemical Engineering, Shandong University, Jinan250100, P. R. China
| | - Yiwei Feng
- School of Chemistry and Chemical Engineering, Shandong University, Jinan250100, P. R. China
| | - Yuxiang Bu
- School of Chemistry and Chemical Engineering, Shandong University, Jinan250100, P. R. China
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5
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Pedersen J, Rasmussen MH, Mikkelsen KV. Redfield Propagation of Photoinduced Electron Transfer Reactions in Vacuum and Solution. J Chem Theory Comput 2022; 18:7052-7072. [PMID: 36413807 DOI: 10.1021/acs.jctc.2c00538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Dynamical simulations of ultrafast electron transfer reactions are of utmost interest. To allow for energy dissipation directly into an external surrounding environment, a solvent coupling model has been deduced, implemented, and utilized to describe the photoinduced electron transfer dynamics within a model triad system herein. The model is based on Redfield theory, and the environment is represented by harmonic oscillators filled with bosonic quanta. To imitate real solvents, the oscillators have been equipped with frequencies and polarization lifetimes characteristic of the corresponding solvent. The population was found to transfer through the energetically lowest electron transfer route regardless of the medium. The condensed population transfer dynamics were observed to be highly dependent on the solvent parameters. In particular, an increase in the solvent coupling entailed a detainment in the population transfer from the initially prepared diabatic state and a promotion in the population transfer through the other electron transfer route. Two explanations based on the diagonal and off-diagonal matrix elements of the Kohn-Sham Fock matrix, respectively, have been provided. The lifetime of the populated partially charge-separated state was prolonged with increasing solvent polarity, and it was explained in terms of attractive interactions between the solvent's dipole moments and the fragments' charges. The high-frequency vibrational fine-structure in the correlation function was demonstrated to be important for the transfer dynamics, and the importance of dephasing effects in polar solvents was verified and precised to concern the optical polarization of the solvents.
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Affiliation(s)
- Jacob Pedersen
- Department of Chemistry, University of Copenhagen, Copenhagen, DK-2100, Denmark
| | - Maria H Rasmussen
- Department of Chemistry, University of Copenhagen, Copenhagen, DK-2100, Denmark
| | - Kurt V Mikkelsen
- Department of Chemistry, University of Copenhagen, Copenhagen, DK-2100, Denmark
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6
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Cabanas AM, Flores Araya JC, Jessop IA, Humire F. Anomalous (Exergonic) Behavior in the Transfer of Electrons between Donors and Acceptors: Mobility, Energy, Caloric Capacity, and Entropy. ACS OMEGA 2022; 7:35153-35158. [PMID: 36211079 PMCID: PMC9535709 DOI: 10.1021/acsomega.2c04094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 09/08/2022] [Indexed: 06/16/2023]
Abstract
Understanding the kinetics of electron transfer reactions involves active research in physics, chemistry, biology, and nano-tech. Here, we propose a model to apply in a broader framework by establishing a connection between thermodynamics and kinetics. From a purely thermodynamic point of view, electronic transfer Marcus' theory is revisited; consequently, calculations of thermodynamic variables such as mobility, energy, and entropy are provided. More significantly, two different regimes are explicitly established. In the anomalous region, an exergonic process associated with negative heat capacity appears. Further, in the same region, mobility, energy, and entropy decrease when the temperature increases.
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Affiliation(s)
- Ana M. Cabanas
- Departamento
de Física, FACI, Universidad de Tarapacá, Arica 1000965, Chile
| | | | - Ignacio A. Jessop
- Departamento
de Química, FACI, Universidad de
Tarapacá, Arica 1000007, Chile
| | - Fernando Humire
- Departamento
de Física, FACI, Universidad de Tarapacá, Arica 1000965, Chile
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7
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Barak A, Dhiman N, Sturm F, Rauch F, Lakshmanna YA, Findlay KS, Beeby A, Marder TB, Umapathy S. Excited‐State Intramolecular Charge‐Transfer Dynamics in 4‐Dimethylamino‐4’‐Cyanodiphenylacetylene: An Ultrafast Raman Loss Spectroscopic Perspective. CHEMPHOTOCHEM 2022. [DOI: 10.1002/cptc.202200146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Arvind Barak
- Indian Institute of Science Department of Inorganic and Physical Chemistry 560012 Bangalore INDIA
| | - Nishant Dhiman
- Indian Institute of Science Department of Inorganic and Physical Chemistry 560012 Bangalore INDIA
| | - Floriane Sturm
- Julius-Maximilians-Universität Würzburg: Julius-Maximilians-Universitat Wurzburg Institut für Anorganische Chemie and Institute for Sustainable Chemistry & Catalysis with Boron (ICB) GERMANY
| | - Florian Rauch
- Julius-Maximilians-Universität Würzburg: Julius-Maximilians-Universitat Wurzburg Institut für Anorganische Chemie and Institute for Sustainable Chemistry & Catalysis with Boron (ICB) GERMANY
| | - Yapamanu Adithya Lakshmanna
- Indian Institute of Science Education and Research Thiruvananthapuram School of Chemistry 695551 Thiruvananthapuram INDIA
| | - Karen S. Findlay
- University of Durham: Durham University Department of Chemistry UNITED KINGDOM
| | - Andrew Beeby
- University of Durham: Durham University Department of Chemistry UNITED KINGDOM
| | - Todd B. Marder
- Julius-Maximilians-Universität Würzburg: Julius-Maximilians-Universitat Wurzburg Institut für Anorganische Chemie and Institute for Sustainable Chemistry & Catalysis with Boron (ICB) GERMANY
| | - Siva Umapathy
- Indian Institute of Science Dept. of Inorganic and physical chemistry Raman avenue 560012 Bangalore INDIA
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8
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Vong A, Mei KJ, Widmer DR, Schwartz BJ. Solvent Control of Chemical Identity Can Change Photodissociation into Photoisomerization. J Phys Chem Lett 2022; 13:7931-7938. [PMID: 35980729 DOI: 10.1021/acs.jpclett.2c01955] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
In solution-phase chemistry, the solvent is often considered to be merely a medium that allows reacting solutes to encounter each other. In this work, however, we show that moderate locally specific solute-solvent interactions can affect not only the nature of the solute but also the types of reactive chemistry. We use quantum simulation methods to explore how solvent participation in solute chemical identity alters reactions involving the breaking of chemical bonds. In particular, we explore the photoexcitation dynamics of Na2+ dissolved in liquid tetrahydrofuran. In the gas phase, excitation of Na2+ directly leads to dissociation, but in solution, photoexcitation leads to an isomerization reaction involving rearrangement of the first-shell solvent molecules; this isomerization must go to completion before the solute can dissociate. Despite the complexity, the solution-phase reaction dynamics can be captured by a two-dimensional energy surface where one dimension involves only the isomerization of the first-shell solvent molecules.
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Affiliation(s)
- Andy Vong
- Department of Chemistry & Biochemistry, University of California, Los Angeles, Los Angeles, California 90095-1569, United States
| | - Kenneth J Mei
- Department of Chemistry & Biochemistry, University of California, Los Angeles, Los Angeles, California 90095-1569, United States
| | - Devon R Widmer
- Department of Chemistry & Biochemistry, University of California, Los Angeles, Los Angeles, California 90095-1569, United States
| | - Benjamin J Schwartz
- Department of Chemistry & Biochemistry, University of California, Los Angeles, Los Angeles, California 90095-1569, United States
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9
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Hou S, Ji X, Gaskell K, Wang PF, Wang L, Xu J, Sun R, Borodin O, Wang C. Solvation sheath reorganization enables divalent metal batteries with fast interfacial charge transfer kinetics. Science 2021; 374:172-178. [PMID: 34618574 DOI: 10.1126/science.abg3954] [Citation(s) in RCA: 109] [Impact Index Per Article: 36.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
[Figure: see text].
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Affiliation(s)
- Singyuk Hou
- Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, MD 20740, USA
| | - Xiao Ji
- Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, MD 20740, USA
| | - Karen Gaskell
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA
| | - Peng-Fei Wang
- Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, MD 20740, USA
| | - Luning Wang
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA
| | - Jijian Xu
- Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, MD 20740, USA
| | - Ruimin Sun
- Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, MD 20740, USA
| | - Oleg Borodin
- Battery Science Branch, Sensors and Electron Devices Directorate, US Army Combat Capabilities Development Command Army Research Laboratory, Adelphi, MD 20783, USA
| | - Chunsheng Wang
- Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, MD 20740, USA
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10
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Biasin E, Fox ZW, Andersen A, Ledbetter K, Kjær KS, Alonso-Mori R, Carlstad JM, Chollet M, Gaynor JD, Glownia JM, Hong K, Kroll T, Lee JH, Liekhus-Schmaltz C, Reinhard M, Sokaras D, Zhang Y, Doumy G, March AM, Southworth SH, Mukamel S, Gaffney KJ, Schoenlein RW, Govind N, Cordones AA, Khalil M. Direct observation of coherent femtosecond solvent reorganization coupled to intramolecular electron transfer. Nat Chem 2021; 13:343-349. [PMID: 33589787 DOI: 10.1038/s41557-020-00629-3] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 12/14/2020] [Indexed: 01/31/2023]
Abstract
It is well known that the solvent plays a critical role in ultrafast electron-transfer reactions. However, solvent reorganization occurs on multiple length scales, and selectively measuring short-range solute-solvent interactions at the atomic level with femtosecond time resolution remains a challenge. Here we report femtosecond X-ray scattering and emission measurements following photoinduced charge-transfer excitation in a mixed-valence bimetallic (FeiiRuiii) complex in water, and their interpretation using non-equilibrium molecular dynamics simulations. Combined experimental and computational analysis reveals that the charge-transfer excited state has a lifetime of 62 fs and that coherent translational motions of the first solvation shell are coupled to the back electron transfer. Our molecular dynamics simulations identify that the observed coherent translational motions arise from hydrogen bonding changes between the solute and nearby water molecules upon photoexcitation, and have an amplitude of tenths of ångströms, 120-200 cm-1 frequency and ~100 fs relaxation time. This study provides an atomistic view of coherent solvent reorganization mediating ultrafast intramolecular electron transfer.
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Affiliation(s)
- Elisa Biasin
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA, USA.
| | - Zachary W Fox
- Department of Chemistry, University of Washington, Seattle, WA, USA
| | - Amity Andersen
- Environmental Molecular Sciences Division, Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Kathryn Ledbetter
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Kasper S Kjær
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA, USA.,Department of Physics, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Roberto Alonso-Mori
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Julia M Carlstad
- Department of Chemistry, University of Washington, Seattle, WA, USA.,Department of Chemistry, University of California, Berkeley, CA, USA
| | - Matthieu Chollet
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - James D Gaynor
- Department of Chemistry, University of Washington, Seattle, WA, USA.,Department of Chemistry, University of California, Berkeley, CA, USA
| | - James M Glownia
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Kiryong Hong
- Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.,Gas Metrology Group, Division of Chemical and Biological Metrology, Korea Research Institute of Standards and Science, Daejeon, Republic of Korea
| | - Thomas Kroll
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Jae Hyuk Lee
- Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.,Pohang Accelerator Laboratory, Pohang, Republic of Korea
| | | | - Marco Reinhard
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Dimosthenis Sokaras
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Yu Zhang
- Department of Chemistry, Physics, and Astronomy, University of California, Irvine, CA, USA.,Q-Chem, Pleasanton, CA, USA
| | - Gilles Doumy
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, IL, USA
| | - Anne Marie March
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, IL, USA
| | - Stephen H Southworth
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, IL, USA
| | - Shaul Mukamel
- Department of Chemistry, Physics, and Astronomy, University of California, Irvine, CA, USA
| | - Kelly J Gaffney
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Robert W Schoenlein
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA, USA.,Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Niranjan Govind
- Physical Sciences Division, Physical and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, USA.
| | - Amy A Cordones
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA, USA.
| | - Munira Khalil
- Department of Chemistry, University of Washington, Seattle, WA, USA.
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11
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Widmer DR, Schwartz BJ. The Role of the Solvent in the Condensed-Phase Dynamics and Identity of Chemical Bonds: The Case of the Sodium Dimer Cation in THF. J Phys Chem B 2020; 124:6603-6616. [PMID: 32603114 DOI: 10.1021/acs.jpcb.0c03298] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
When a solute molecule is placed in solution, is it acceptable to presume that its electronic structure is essentially the same as that in the gas phase? In this paper, we address this question from a simulation perspective for the case of the sodium dimer cation (Na2+) molecule in both liquid Ar and liquid tetrahydrofuran (THF). In previous work, we showed that, when local specific interactions between a solute and solvent are energetically on the order of a hydrogen bond, the solvent can become part of the chemical identity of the solute. Here, using mixed quantum/classical molecular dynamics simulations, we see that, for the Na2+ molecule, solute-solvent interactions lead to two stable, chemically distinct coordination states (Na(THF)4-Na(THF)5+ and Na(THF)5-Na(THF)5+) that are not only stable themselves as gas-phase molecules but that also have a completely new electronic structure with important implications for the excited-state photodissociation of this molecule in the condensed phase. Furthermore, we show through a set of comparative classical simulations that treating the solute's bonding electron explicitly quantum mechanically is necessary to understand both the ground-state dynamics and chemical identity of this simple diatomic molecule; even use of the quantum-derived potential of mean force is insufficient to describe the behavior of the molecule classically. Finally, we calculate the results of a proposed transient hole-burning experiment that could be used to spectroscopically disentangle the presence of the different coordination states.
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Affiliation(s)
- Devon R Widmer
- Department of Chemistry & Biochemistry, University of California, Los Angeles, Los Angeles, California 90095-1569, United States
| | - Benjamin J Schwartz
- Department of Chemistry & Biochemistry, University of California, Los Angeles, Los Angeles, California 90095-1569, United States
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12
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Bhattacharyya D, Mizuno H, Rizzuto AM, Zhang Y, Saykally RJ, Bradforth SE. New Insights into the Charge-Transfer-to-Solvent Spectrum of Aqueous Iodide: Surface versus Bulk. J Phys Chem Lett 2020; 11:1656-1661. [PMID: 32040333 DOI: 10.1021/acs.jpclett.9b03857] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Liquid phase charge-transfer-to-solvent (CTTS) transitions are important, as they serve as photochemical routes to solvated electrons. In this work, broadband deep-ultraviolet electronic sum frequency generation (DUV-ESFG) and two-photon absorption (2PA) spectroscopic techniques were used to assign and compare the nature of the aqueous iodide CTTS excitations at the air/water interface and in bulk solution. In the one-photon absorption (1PA) spectrum, excitation to the 6s Rydberg-like orbital (5p → 6s) gives rise to a pair of spin-orbit split iodine states, 2P3/2 and 2P1/2. In the 2PA spectra, the lower-energy 2P3/2 peak is absent and the observed 2PA peak, which is ∼0.14 eV blue-shifted relative to the upper 2P1/2 CTTS peak seen in 1PA, arises from 5p → 6p electronic promotion. The band observed in the ESFG spectrum is attributed to mixing of excited states involving 5p → 6p and 5p → 6s promotions caused by both vibronic coupling and the external electric field generated by asymmetric interfacial solvation.
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Affiliation(s)
- Dhritiman Bhattacharyya
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
| | - Hikaru Mizuno
- Department of Chemistry, University of California, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Anthony M Rizzuto
- Department of Chemistry, University of California, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Yuyuan Zhang
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
| | - Richard J Saykally
- Department of Chemistry, University of California, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Stephen E Bradforth
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
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13
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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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14
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Percino MJ, Cerón M, Venkatesan P, Pérez-Gutiérrez E, Santos P, Ceballos P, Castillo AE, Gordillo-Guerra P, Anandhan K, Barbosa-García O, Bernal W, Thamotharan S. A low molecular weight OLED material: 2-(4-((2-hydroxyethyl)(methyl)amino)benzylidene)malononitrile. Synthesis, crystal structure, thin film morphology, spectroscopic characterization and DFT calculations. RSC Adv 2019; 9:28704-28717. [PMID: 35529660 PMCID: PMC9071261 DOI: 10.1039/c9ra05425a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 09/05/2019] [Indexed: 01/15/2023] Open
Abstract
2-(4-((2-Hydroxyethyl)(methyl)amino)benzylidene)malononitrile (HEMABM) was synthesized from 4-[hydroxymethyl(methyl)amino]benzaldehyde and propanedinitrile to obtain a low molecular weight fluorescent material with an efficient solid-state emission and electroluminescence properties comparable to the well-known poly(2-methoxy-5(2'-ethyl)hexoxyphenylenevinylene) (MEH-PPV). The HEMABM was used to prepare an organic light-emitting diode by a solution process. Despite the title compound being a small molecule, it showed optical properties and notable capacity to form a film with smooth morphology (10.81 nm) closer to that of polymer MEH-PPV (10.63 nm). The preparation of the device was by spin coating, the electrical properties such as threshold voltage were about 1.0 V for both HEMABM and MEH-PPV, and the luminance 1300 cd m-2 for HEMABM and 2600 cd m-2 for MEH-PPV. This low molecular weight compound was characterized by SCXRD, IR, NMR, and EI. Besides a quantitative analysis of the intermolecular interactions by PIXEL, density functional theory (DFT) calculations are reported.
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Affiliation(s)
- M Judith Percino
- Unidad de Polímeros y Electrónica Orgánica, ICUAP, Benemérita Universidad Autónoma de Puebla Val 3-Ecocampus Valsequillo, Independencia O2 Sur 50, San Pedro Zacachimalpa Pue. Mexico 7296
| | - Margarita Cerón
- Unidad de Polímeros y Electrónica Orgánica, ICUAP, Benemérita Universidad Autónoma de Puebla Val 3-Ecocampus Valsequillo, Independencia O2 Sur 50, San Pedro Zacachimalpa Pue. Mexico 7296
| | - Perumal Venkatesan
- Unidad de Polímeros y Electrónica Orgánica, ICUAP, Benemérita Universidad Autónoma de Puebla Val 3-Ecocampus Valsequillo, Independencia O2 Sur 50, San Pedro Zacachimalpa Pue. Mexico 7296
| | - Enrique Pérez-Gutiérrez
- Unidad de Polímeros y Electrónica Orgánica, ICUAP, Benemérita Universidad Autónoma de Puebla Val 3-Ecocampus Valsequillo, Independencia O2 Sur 50, San Pedro Zacachimalpa Pue. Mexico 7296
| | - Pilar Santos
- Unidad de Polímeros y Electrónica Orgánica, ICUAP, Benemérita Universidad Autónoma de Puebla Val 3-Ecocampus Valsequillo, Independencia O2 Sur 50, San Pedro Zacachimalpa Pue. Mexico 7296
| | - Paulina Ceballos
- Unidad de Polímeros y Electrónica Orgánica, ICUAP, Benemérita Universidad Autónoma de Puebla Val 3-Ecocampus Valsequillo, Independencia O2 Sur 50, San Pedro Zacachimalpa Pue. Mexico 7296
| | - Armando E Castillo
- Unidad de Polímeros y Electrónica Orgánica, ICUAP, Benemérita Universidad Autónoma de Puebla Val 3-Ecocampus Valsequillo, Independencia O2 Sur 50, San Pedro Zacachimalpa Pue. Mexico 7296
| | - Paola Gordillo-Guerra
- Unidad de Polímeros y Electrónica Orgánica, ICUAP, Benemérita Universidad Autónoma de Puebla Val 3-Ecocampus Valsequillo, Independencia O2 Sur 50, San Pedro Zacachimalpa Pue. Mexico 7296
| | - Karnambaram Anandhan
- Unidad de Polímeros y Electrónica Orgánica, ICUAP, Benemérita Universidad Autónoma de Puebla Val 3-Ecocampus Valsequillo, Independencia O2 Sur 50, San Pedro Zacachimalpa Pue. Mexico 7296
| | | | - Wilson Bernal
- Centro de Investigaciones en Óptica A. P. 1-948 37150 León Guanajuato Mexico
| | - Subbiah Thamotharan
- Biomolecular Crystallography Laboratory, Department of Bioinformatics, School of Chemical and Biotechnology, SASTRA Deemed University Thanjavur 613 401 India
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15
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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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16
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Slanina T, Oberschmid T. Rhodamine 6G Radical: A Spectro (Fluoro) Electrochemical and Transient Spectroscopic Study. ChemCatChem 2018. [DOI: 10.1002/cctc.201800971] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Tomáš Slanina
- Department of Chemistry and RECETOX Faculty of Science; Masaryk University; Kamenice 5 625 00 Brno Czech Republic
- Institute of Organic Chemistry and Chemical Biology; Goethe University Frankfurt; 60323 Frankfurt am Main Germany
| | - Teresa Oberschmid
- Institute of Organic Chemistry Faculty of Chemistry and Pharmacy; University of Regensburg; 93040 Regensburg Germany
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17
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Solvents can control solute molecular identity. Nat Chem 2018; 10:910-916. [PMID: 29785032 DOI: 10.1038/s41557-018-0066-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Accepted: 04/13/2018] [Indexed: 11/08/2022]
Abstract
For solution-phase chemical reactions, the solvent is often considered simply as a medium to allow the reactants to encounter each other by diffusion. Although examples of direct solvent effects on molecular solutes exist, such as the compression of solute bonding electrons due to Pauli repulsion interactions, the solvent is not usually considered a part of the chemical species of interest. We show, using quantum simulations of Na2, that when there are local specific interactions between a solute and solvent that are energetically on the same order as a hydrogen bond, the solvent controls not only the bond dynamics but also the chemical identity of the solute. In tetrahydrofuran, dative bonding interactions between the solvent and Na atoms lead to unique coordination states that must cross a free energy barrier of ~8 kBT-undergoing a chemical reaction-to interconvert. Each coordination state has its own dynamics and spectroscopic signatures, highlighting the importance of considering the solvent in the identity of condensed-phase chemical systems.
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18
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Gupta S, Kumar A, Joshi KB. Study of electron transfer process in aqueous methanol system by using tryptophan based short peptide – Amino acid pairs. J Photochem Photobiol A Chem 2018. [DOI: 10.1016/j.jphotochem.2018.01.041] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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19
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Deng GH, Shen Y, He Z, Zhang Q, Jiang B, Yuan K, Wu G, Yang X. The molecular rotational motion of liquid ethanol studied by ultrafast time resolved infrared spectroscopy. Phys Chem Chem Phys 2018; 19:4345-4351. [PMID: 28119958 DOI: 10.1039/c6cp07380h] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this report, ultrafast time-resolved infrared spectroscopy is used to study the rotational motion of the liquid ethanol molecule. The results showed that the methyl, methylene, and CO groups have close rotational relaxation times, 1-2 ps, and the rotational relaxation time of the hydroxyl group (-OH) is 8.1 ps. The fast motion of the methyl, methylene and CO groups, and the slow motion of the hydroxyl group suggested that the ethanol molecules experience anisotropic motion in the liquid phase. The slow motion of the hydroxyl group also shows that the hydrogen bonded network could be considered as an effective molecule. The experimental data provided in this report are helpful for theorists to build models to understand the molecular rotational motion of liquid ethanol. Furthermore, our experimental method, which can provide more data concerning the rotational motion of sub groups of liquid molecules, will be useful for understanding the complicated molecular motion in the liquid phase.
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Affiliation(s)
- Gang-Hua Deng
- State key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China.
| | - Yuneng Shen
- State key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China. and Tongji Zhejiang College, Jiaxing 314000, Zhejiang, China
| | - Zhigang He
- State key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China.
| | - Qiang Zhang
- Institute of Chemistry & Chemical Engineering, Bohai University, Jinzhou 121000, China
| | - Bo Jiang
- State key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China.
| | - Kaijun Yuan
- State key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China.
| | - Guorong Wu
- State key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China.
| | - Xueming Yang
- State key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China.
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20
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Farr EP, Zho CC, Challa JR, Schwartz BJ. Temperature dependence of the hydrated electron’s excited-state relaxation. II. Elucidating the relaxation mechanism through ultrafast transient absorption and stimulated emission spectroscopy. J Chem Phys 2017; 147:074504. [DOI: 10.1063/1.4985906] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Affiliation(s)
- Erik P. Farr
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, USA
| | - Chen-Chen Zho
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, USA
| | - Jagannadha R. Challa
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, USA
| | - Benjamin J. Schwartz
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, USA
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21
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Bhat MA, Ingole PP, Randriamahazaka H. Towards Understanding the Solvent-Dynamic Control of the Transport and Heterogeneous Electron-Transfer Processes in Ionic Liquids. Chemphyschem 2017; 18:415-426. [PMID: 27922206 DOI: 10.1002/cphc.201600442] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Revised: 12/01/2016] [Indexed: 12/24/2022]
Abstract
The impact of temperature-induced changes in solvent dynamics on the diffusion coefficient and standard rate constant k0 for heterogeneous electron transfer (ET) of ethylferrocene (EFc) in 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6 ]) is investigated. The results are analysed to understand the impact of solvent-dynamic control, solute-solvent interactions and solvent friction on the transport of redox probes and k0 . Concentration dependence of the diffusion coefficient of EFc in [BMIM][PF6 ] is observed. This is attributed to the solute-induced enhancement of the structural organisation of the ionic liquid (IL), which is supported by the concentration-dependent UV/Vis absorption and photoluminescence responses of EFc/[BMIM][PF6 ] solutions. Similar values of the activation energies for mass transport and ET and a linear relationship between the diffusion coefficient and the heterogeneous ET rate is observed. The ratio between the diffusion coefficient and the heterogeneous rate constant allows a characteristic length Ld , which is temperature-independent, to be introduced. The presented results clearly establish that mass transport and heterogeneous ET of redox probes are strongly correlated in ILs. It is proposed that the apparent kinetics of heterogeneous ET reactions in ILs can be explained in terms of their impact on thermal equilibration, energy dissipation and thermal excitation of redox-active probes.
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Affiliation(s)
- Mohsin Ahmad Bhat
- Department of Chemistry, University of Pune, Ganeshkhind, Pune, 411007, India), Fax: (+91) 194-2414049, E-mail
| | - Pravin P Ingole
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, 110016, India
| | - Hyacinthe Randriamahazaka
- Université Paris Diderot, Sorbonne Paris Cité, ITODYS, UMR 7086 CNRS, 15 rue Jean-Antoine de Baïf, 75205, Paris Cedex 13, France
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22
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Dohn AO, Kjær KS, Harlang TB, Canton SE, Nielsen MM, Møller KB. Electron Transfer and Solvent-Mediated Electronic Localization in Molecular Photocatalysis. Inorg Chem 2016; 55:10637-10644. [DOI: 10.1021/acs.inorgchem.6b01840] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Asmus O. Dohn
- Department of Chemistry, Technical University of Denmark, Kemitorvet 206, 2800 Kgs Lyngby, Denmark
| | - Kasper S. Kjær
- Department of Physics, Technical University of Denmark, Building 307 2800 Kgs. Lyngby, Denmark
| | - Tobias B. Harlang
- Department of Physics, Technical University of Denmark, Building 307 2800 Kgs. Lyngby, Denmark
| | - Sophie E. Canton
- Center for
Ultrafast Imaging, University of Hamburg, 22761 Hamburg, Germany
| | - Martin M. Nielsen
- Department of Physics, Technical University of Denmark, Building 307 2800 Kgs. Lyngby, Denmark
| | - Klaus B. Møller
- Department of Chemistry, Technical University of Denmark, Kemitorvet 206, 2800 Kgs Lyngby, Denmark
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23
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Kanjana K, Courtin B, MacConnell A, Bartels DM. Reactions of Hexa-aquo Transition Metal Ions with the Hydrated Electron up to 300 °C. J Phys Chem A 2015; 119:11094-104. [DOI: 10.1021/acs.jpca.5b08812] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Kotchaphan Kanjana
- Notre Dame Radiation Laboratory & Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556 United States
| | - Bruce Courtin
- Notre Dame Radiation Laboratory & Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556 United States
| | - Ashley MacConnell
- Notre Dame Radiation Laboratory & Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556 United States
| | - David M. Bartels
- Notre Dame Radiation Laboratory & Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556 United States
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24
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Zheng S, Geva E, Dunietz BD. Solvated Charge Transfer States of Functionalized Anthracene and Tetracyanoethylene Dimers: A Computational Study Based on a Range Separated Hybrid Functional and Charge Constrained Self-Consistent Field with Switching Gaussian Polarized Continuum Models. J Chem Theory Comput 2013; 9:1125-31. [DOI: 10.1021/ct300700q] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Shaohui Zheng
- Department of Chemistry, University
of Michigan, Ann Arbor, Michigan 48109, United States
| | - Eitan Geva
- Department of Chemistry, University
of Michigan, Ann Arbor, Michigan 48109, United States
| | - Barry D. Dunietz
- Department of Chemistry, Kent
State University, Kent, Ohio 44242, United States
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25
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Thayer MP, McGuire C, Stennett EMS, Lockhart MK, Canache D, Novak M, Schmidtke SJ. pH-dependent spectral properties of para-aminobenzoic acid and its derivatives. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2011; 84:227-232. [PMID: 21993255 DOI: 10.1016/j.saa.2011.09.032] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Revised: 09/09/2011] [Accepted: 09/13/2011] [Indexed: 05/31/2023]
Abstract
The local environment dictates the structural and functional properties of many important chemical and biological systems. The impact of pH on the photophysical properties of a series of para-aminobenzoic acids is examined using a combination of experimental spectroscopy and quantum chemical calculations. Following photoexcitation, PABA derivatives may undergo an intramolecular charge transfer (ICT) resulting in the formation of a zwitterionic species. The thermodynamics of the excited state reaction and temperature-dependence of the radiative emission processes are evaluated through variable temperature fluorescence spectroscopy carried out in a range of aqueous buffers. Quantum chemical calculations are used to analyze structural changes with modifications at the amine position and different protonation states. The ICT is only observed in the tertiary amine, which calculations show has more sp(2) character than the primary or secondary amines. Thermodynamic analysis indicates the ICT reaction is driven by entropy.
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LI XIANGYUAN, FU KEXIANG. CONTINUOUS MEDIUM THEORY FOR NONEQUILIBRIUM SOLVATION: NEW FORMULATIONS AND AN OVERVIEW OF THEORIES AND APPLICATIONS. JOURNAL OF THEORETICAL & COMPUTATIONAL CHEMISTRY 2011. [DOI: 10.1142/s0219633605001830] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
- XIANG-YUAN LI
- College of Chemical Engineering, Sichuan University, Chengdu 610065, P. R. China
| | - KE-XIANG FU
- College of Physics, Sichuan University, Chengdu 610064, P. R. China
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27
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Laird BB, Thompson WH. Time-dependent fluorescence in nanoconfined solvents: Linear-response approximations and Gaussian statistics. J Chem Phys 2011; 135:084511. [DOI: 10.1063/1.3626825] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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28
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Tripathy J, Beck WF. Nanosecond-Regime Correlation Time Scales for Equilibrium Protein Structural Fluctuations of Metal-Free Cytochrome c from Picosecond Time-Resolved Fluorescence Spectroscopy and the Dynamic Stokes Shift. J Phys Chem B 2010; 114:15958-68. [DOI: 10.1021/jp1044964] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Jagnyaseni Tripathy
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
| | - Warren F. Beck
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
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29
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Glover WJ, Larsen RE, Schwartz BJ. First principles multielectron mixed quantum/classical simulations in the condensed phase. I. An efficient Fourier-grid method for solving the many-electron problem. J Chem Phys 2010; 132:144101. [DOI: 10.1063/1.3352564] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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30
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Glover WJ, Larsen RE, Schwartz BJ. First principles multielectron mixed quantum/classical simulations in the condensed phase. II. The charge-transfer-to-solvent states of sodium anions in liquid tetrahydrofuran. J Chem Phys 2010; 132:144102. [DOI: 10.1063/1.3352565] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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31
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Larsen MC, Schwartz BJ. Searching for solvent cavities via electron photodetachment: The ultrafast charge-transfer-to-solvent dynamics of sodide in a series of ether solvents. J Chem Phys 2009; 131:154506. [DOI: 10.1063/1.3245864] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
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32
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Glover WJ, Larsen RE, Schwartz BJ. The roles of electronic exchange and correlation in charge-transfer-to-solvent dynamics: Many-electron nonadiabatic mixed quantum/classical simulations of photoexcited sodium anions in the condensed phase. J Chem Phys 2008; 129:164505. [DOI: 10.1063/1.2996350] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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33
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Schmidhammer U, Megerle U, Lochbrunner S, Riedle E, Karpiuk J. The Key Role of Solvation Dynamics in Intramolecular Electron Transfer: Time-Resolved Photophysics of Crystal Violet Lactone. J Phys Chem A 2008; 112:8487-96. [DOI: 10.1021/jp800863u] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Uli Schmidhammer
- Lehrstuhl für BioMolekulare Optik, Ludwig-Maximilians-Universität (LMU), Oettingenstr. 67, 80538 München, Germany, and Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Uwe Megerle
- Lehrstuhl für BioMolekulare Optik, Ludwig-Maximilians-Universität (LMU), Oettingenstr. 67, 80538 München, Germany, and Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Stefan Lochbrunner
- Lehrstuhl für BioMolekulare Optik, Ludwig-Maximilians-Universität (LMU), Oettingenstr. 67, 80538 München, Germany, and Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Eberhard Riedle
- Lehrstuhl für BioMolekulare Optik, Ludwig-Maximilians-Universität (LMU), Oettingenstr. 67, 80538 München, Germany, and Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Jerzy Karpiuk
- Lehrstuhl für BioMolekulare Optik, Ludwig-Maximilians-Universität (LMU), Oettingenstr. 67, 80538 München, Germany, and Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
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Goldsmith RH, Vura-Weis J, Scott AM, Borkar S, Sen A, Ratner MA, Wasielewski MR. Unexpectedly Similar Charge Transfer Rates through Benzo-Annulated Bicyclo[2.2.2]octanes. J Am Chem Soc 2008; 130:7659-69. [DOI: 10.1021/ja8004623] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Randall H. Goldsmith
- Department of Chemistry, Argonne-Northwestern Solar Energy Research (ANSER) Center, and International Institute for Nanotechnology, Northwestern University, Evanston, Illinois 60208 and the Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - Josh Vura-Weis
- Department of Chemistry, Argonne-Northwestern Solar Energy Research (ANSER) Center, and International Institute for Nanotechnology, Northwestern University, Evanston, Illinois 60208 and the Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - Amy M. Scott
- Department of Chemistry, Argonne-Northwestern Solar Energy Research (ANSER) Center, and International Institute for Nanotechnology, Northwestern University, Evanston, Illinois 60208 and the Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - Sachin Borkar
- Department of Chemistry, Argonne-Northwestern Solar Energy Research (ANSER) Center, and International Institute for Nanotechnology, Northwestern University, Evanston, Illinois 60208 and the Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - Ayusman Sen
- Department of Chemistry, Argonne-Northwestern Solar Energy Research (ANSER) Center, and International Institute for Nanotechnology, Northwestern University, Evanston, Illinois 60208 and the Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - Mark A. Ratner
- Department of Chemistry, Argonne-Northwestern Solar Energy Research (ANSER) Center, and International Institute for Nanotechnology, Northwestern University, Evanston, Illinois 60208 and the Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - Michael R. Wasielewski
- Department of Chemistry, Argonne-Northwestern Solar Energy Research (ANSER) Center, and International Institute for Nanotechnology, Northwestern University, Evanston, Illinois 60208 and the Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802
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Winter B, Aziz EF, Ottosson N, Faubel M, Kosugi N, Hertel IV. Electron dynamics in charge-transfer-to-solvent states of aqueous chloride revealed by Cl- 2p resonant Auger-electron spectroscopy. J Am Chem Soc 2008; 130:7130-8. [PMID: 18461939 DOI: 10.1021/ja8009742] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Charge-transfer-to-solvent (CTTS) excited states of aqueous chloride are studied by a novel experimental approach based on resonant inner-shell photoexcitation, Cl(-)aq 2p --> e(i), i = 1-4, which denotes a series of excitations to lowest and higher CTTS states. These states are clearly identified through the occurrence of characteristic spectator Auger decays to double Cl 3p valence-hole states, where the CTTS states can be more stabilized as compared to single Cl(-)aq 2p core excitations and optical valence excitations. Furthermore, we have found for the first time that the CTTS electron e(i) bound by a single Cl 2p hole not only behaves as a spectator e(i) --> e'(i), bound by a double valence-hole state before relaxation of the excited electron (i) itself, but also shows electron dynamics to the relaxed lowest state, e(i) --> e'(1*). This interpretation is supported by ab initio calculations. The key to performing photoelectron and Auger-electron spectroscopy studies from aqueous solutions is the use of a liquid microjet in ultrahigh vacuum in conjunction with synchrotron radiation.
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Affiliation(s)
- Bernd Winter
- Max-Born-Institut für Nichtlineare Optik and Kurzzeitspektroskopie, Max-Born-Strasse 2A, D-12489 Berlin, Germany.
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Affiliation(s)
- Xiyi Chen
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482;
| | - Stephen E. Bradforth
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482;
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Bragg AE, Schwartz BJ. Ultrafast Charge-Transfer-to-Solvent Dynamics of Iodide in Tetrahydrofuran. 2. Photoinduced Electron Transfer to Counterions in Solution. J Phys Chem A 2008; 112:3530-43. [DOI: 10.1021/jp712039u] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Arthur E. Bragg
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California 90095-1569
| | - Benjamin J. Schwartz
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California 90095-1569
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Bragg AE, Schwartz BJ. The ultrafast charge-transfer-to-solvent dynamics of iodide in tetrahydrofuran. 1. Exploring the roles of solvent and solute electronic structure in condensed-phase charge-transfer reactions. J Phys Chem B 2007; 112:483-94. [PMID: 18085770 DOI: 10.1021/jp076934s] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Although they represent the simplest possible charge-transfer reactions, the charge-transfer-to-solvent (CTTS) dynamics of atomic anions exhibit considerable complexity. For example, the CTTS dynamics of iodide in water are very different from those of sodide (Na-) in tetrahydrofuran (THF), leading to the question of the relative importance of the solvent and solute electronic structures in controlling charge-transfer dynamics. In this work, we address this issue by investigating the CTTS spectroscopy and dynamics of I- in THF, allowing us to make detailed comparisons to the previously studied I-/H2O and Na-/THF CTTS systems. Since THF is weakly polar, ion pairing with the counterion can have a substantial impact on the CTTS spectroscopy and dynamics of I- in this solvent. In this study, we have isolated "counterion-free" I- in THF by complexing the Na+ counterion with 18-crown-6 ether. Ultrafast pump-probe experiments reveal that THF-solvated electrons (e-THF) appear 380 +/- 60 fs following the CTTS excitation of "free" I- in THF. The absorption kinetics are identical at all probe wavelengths, indicating that the ejected electrons appear with no significant dynamic solvation but rather with their equilibrium absorption spectrum. After their initial appearance, ejected electrons do not exhibit any additional dynamics on time scales up to approximately 1 ns, indicating that geminate recombination of e-THF with its iodine atom partner does not occur. Competitive electron scavenging measurements demonstrate that the CTTS excited state of I- in THF is quite large and has contact with scavengers that are several nanometers away from the iodide ion. The ejection time and lack of electron solvation observed for I- in THF are similar to what is observed following CTTS excitation of Na- in THF. However, the relatively slow ejection time, the complete lack of dynamic solvation, and the large ejection distance/lack of recombination dynamics are in marked contrast to the CTTS dynamics observed for I- in water, in which fast electron ejection, substantial solvation, and appreciable recombination have been observed. These differences in dynamical behavior can be understood in terms of the presence of preexisting, electropositive cavities in liquid THF that are a natural part of its liquid structure; these cavities provide a mechanism for excited electrons to relocate to places in the liquid that can be nanometers away, explaining the large ejection distance and lack of recombination following the CTTS excitation of I- in THF. We argue that the lack of dynamic solvation observed following CTTS excitation of both I- and Na- in THF is a direct consequence of the fact that little additional relaxation is required once an excited electron nonadiabatically relaxes into one of the preexisting cavities. In contrast, liquid water contains no such cavities, and CTTS excitation of I- in water leads to local electron ejection that involves substantial solvent reorganization.
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Affiliation(s)
- Arthur E Bragg
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California 90095-1569, USA
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39
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Cui Q, Li L, Wu F, Jiang X, Li W, Möhwald H. Photoinduced voltage changes inside polarity gradient films. Colloids Surf A Physicochem Eng Asp 2007. [DOI: 10.1016/j.colsurfa.2007.02.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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40
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Cavanagh MC, Larsen RE, Schwartz BJ. Watching Na Atoms Solvate into (Na+,e-) Contact Pairs: Untangling the Ultrafast Charge-Transfer-to-Solvent Dynamics of Na- in Tetrahydrofuran (THF). J Phys Chem A 2007; 111:5144-57. [PMID: 17523607 DOI: 10.1021/jp071132i] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
With the large dye molecules employed in typical studies of solvation dynamics, it is often difficult to separate the intramolecular relaxation of the dye from the relaxation associated with dynamic solvation. One way to avoid this difficulty is to study solvation dynamics using an atom as the solvation probe; because atoms have only electronic degrees of freedom, all of the observed spectroscopic dynamics must result from motions of the solvent. In this paper, we use ultrafast transient absorption spectroscopy to investigate the solvation dynamics of newly created sodium atoms that are formed following the charge transfer to solvent (CTTS) ejection of an electron from sodium anions (sodide) in liquid tetrahydrofuran (THF). Because the absorption spectra of the sodide reactant, the sodium atom, and the solvated electron products overlap, we first examined the dynamics of the ejected CTTS electron in the infrared to build a detailed model of the CTTS process that allowed us to subtract the spectroscopic contributions of the sodide bleach and the solvated electron and cleanly reveal the spectroscopy of the solvated atom. We find that the neutral sodium species created following CTTS excitation of sodide initially absorbs near 590 nm, the position of the gas-phase sodium D-line, suggesting that it only weakly interacts with the surrounding solvent. We then see a fast solvation process that causes a red-shift of the sodium atom's spectrum in approximately 230 fs, a time scale that matches well with the results of MD simulations of solvation dynamics in liquid THF. After the fast solvation is complete, the neutral sodium atoms undergo a chemical reaction that takes place in approximately 740 fs, as indicated by the observation of an isosbestic point and the creation of a species with a new spectrum. The spectrum of the species created after the reaction then red-shifts on a approximately 10-ps time scale to become the equilibrium spectrum of the THF-solvated sodium atom, which is known from radiation chemistry experiments to absorb near approximately 900 nm. There has been considerable debate as to whether this 900-nm absorbing species is better thought of as a solvated atom or a sodium cation:solvated electron contact pair, (Na+,e-). The fact that we observe the initially created neutral Na atom undergoing a chemical reaction to ultimately become the 900-nm absorbing species suggests that it is better assigned as (Na+,e-). The approximately 10-ps solvation time we observe for this species is an order of magnitude slower than any other solvation process previously observed in liquid THF, suggesting that this species interacts differently with the solvent than the large molecules that are typically used as solvation probes. Together, all of the results allow us to build the most detailed picture to date of the CTTS process of Na- in THF as well as to directly observe the solvation dynamics associated with single sodium atoms in solution.
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Affiliation(s)
- Molly C Cavanagh
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California 90095-1569, USA
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41
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D'Alessandro DM, Junk PC, Richard Keene F. Differential Ion-pairing and Temperature Effects on Intervalence Charge Transfer (IVCT) in a Series of Dinuclear Ruthenium Complexes. Supramol Chem 2007. [DOI: 10.1080/10610270500310537] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Deanna M. D'Alessandro
- a School of Pharmacy & Molecular Sciences, James Cook University , Townsville, Queensland, 4811, Australia
| | - Peter C. Junk
- b School of Chemistry, Monash University , Clayton, Victoria, 3182, Australia
| | - F. Richard Keene
- a School of Pharmacy & Molecular Sciences, James Cook University , Townsville, Queensland, 4811, Australia
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42
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Smallwood CJ, Mejia CN, Glover WJ, Larsen RE, Schwartz BJ. A computationally efficient exact pseudopotential method. II. Application to the molecular pseudopotential of an excess electron interacting with tetrahydrofuran (THF). J Chem Phys 2006; 125:074103. [PMID: 16942318 DOI: 10.1063/1.2218835] [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: 02/03/2023] Open
Abstract
In the preceding paper, we presented an analytic reformulation of the Phillips-Kleinman (PK) pseudopotential theory. In the PK theory, the number of explicitly treated electronic degrees of freedom in a multielectron problem is reduced by forcing the wave functions of the few electrons of interest (the valence electrons) to be orthogonal to those of the remaining electrons (the core electrons); this results in a new Schrodinger equation for the valence electrons in which the effects of the core electrons are treated implicitly via an extra term known as the pseudopotential. Although this pseudopotential must be evaluated iteratively, our reformulation of the theory allows the exact pseudopotential to be found without ever having to evaluate the potential energy operator, providing enormous computational savings. In this paper, we present a detailed computational procedure for implementing our reformulation of the PK theory, and we illustrate our procedure on the largest system for which an exact pseudopotential has been calculated, that of an excess electron interacting with a tetrahyrdrofuran (THF) molecule. We discuss the numerical stability of several approaches to the iterative solution for the pseudopotential, and find that once the core wave functions are available, the full e(-)-THF pseudopotential can be calculated in less than 3 s on a relatively modest single processor. We also comment on how the choice of basis set affects the calculated pseudopotential, and provide a prescription for correcting unphysical behavior that arises at long distances if a localized Gaussian basis set is used. Finally, we discuss the effective e(-)-THF potential in detail, and present a multisite analytic fit of the potential that is suitable for use in molecular simulation.
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Affiliation(s)
- C Jay Smallwood
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California 90095-1569, USA
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43
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D'Alessandro DM, Keene FR. Intervalence Charge Transfer (IVCT) in Trinuclear and Tetranuclear Complexes of Iron, Ruthenium, and Osmium. Chem Rev 2006; 106:2270-98. [PMID: 16771450 DOI: 10.1021/cr050010o] [Citation(s) in RCA: 272] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Deanna M D'Alessandro
- School of Pharmacy & Molecular Sciences, James Cook University, Townsville, Queensland 4811, Australia
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D’Alessandro DM, Keene FR. Diastereoisomers as probes for solvent reorganizational effects on IVCT in dinuclear ruthenium complexes. Chem Phys 2006. [DOI: 10.1016/j.chemphys.2005.09.016] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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45
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Shoshana O, Pérez Lustres JL, Ernsting NP, Ruhman S. Mapping CTTS dynamics of Na−in tetrahydrofurane with ultrafast multichannel pump–probe spectroscopy. Phys Chem Chem Phys 2006; 8:2599-609. [PMID: 16738713 DOI: 10.1039/b602933g] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Using multichannel femtosecond spectroscopy we have followed Na- charge transfer to solvent (CTTS) dynamics in THF solution. Absorption of the primary photoproducts in the visible, resolved here for the first time, consists of an asymmetric triplet centered at 595 nm, which we assign to a metastable incompletely solvated neutral atomic sodium species. Decay of this feature within approximately 1 ps to a broad and structureless solvated neutral is accompanied by broadening and loss of spectral detail. Kinetic analysis shows that both the spectral structure and the decay of this band are independent of the excitation photon frequency in the range 400-800 nm. With different pump-probe polarizations the anisotropy in transient transmission has been charted and its variation with excitation wavelength surveyed. The anisotropies are assigned to the reactant bleach, indicating that due to solvent-induced symmetry breaking, the CTTS absorption band of Na- is made up of discreet orthogonally polarized sub bands. None of the anisotropy in transient absorption could be associated with the photoproduct triplet band even at the earliest measurable time delays. Along with the documented differences in the spatial distribution of ejected electrons across the tested excitation wavelength range, these results lead us to conclude that photoejection is extremely rapid, and that loss of correlations between the departing electron and its neutral core is faster than our time resolution of approximately 60 fs.
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Affiliation(s)
- O Shoshana
- Department of Physical Chemistry, and the Farkas Center for Light Induced Processes, the Hebrew University, Jerusalem, 91904, Israel.
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Dermota TE, Hydutsky DP, Bianco NJ, Castleman AW. Excited-State Dynamics of (SO2)m Clusters. J Phys Chem A 2005; 109:8259-67. [PMID: 16834213 DOI: 10.1021/jp052529u] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A study of the excited-state dynamics of (SO2)m clusters following excitation by ultrafast laser pulses in the range of 4.5 eV (coupled 1A2, 1B1 states) and 9 eV (F band) is presented. The findings for the coupled 1A2 and 1B1 states are in good agreement with published computational work on the properties of these coupled states. A mechanism involving charge transfer to solvent is put forward as the source of the excited-state dynamics that follow the excitation of the SO2 F band within (SO2)m+1 clusters with m > 1. The proposed CTTS mechanism is supported by calculations of the energetics of the process and the observed trends in the excited-state lifetimes that correlate very well with the calculated energies.
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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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47
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Costentin C, Robert M, Savéant JM. Stepwise and concerted electron-transfer/bond breaking reactions. solvent control of the existence of unstable pi ion radicals and of the activation barriers of their heterolytic cleavage. J Am Chem Soc 2005; 126:16834-40. [PMID: 15612722 DOI: 10.1021/ja045294t] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Available data from various sources seem to indicate an important role of solvation in the cleavage rates of intermediate pi ion radicals, in the passage from concerted to stepwise electron-transfer/bond breaking reaction pathways and even in the very existence of pi ion radicals. After preliminary computations treating the solvent as dielectric continuum, these expectations are examined with the help of a simple model system involving the anion radical of ONCH(2)Cl and two molecules of water, which allows the application of advanced computational techniques and a treatment of these solvent effects that emphasizes the role of solvent molecules that sit close to the charge centers of the molecule. A pi ion radical minimum indeed appears upon introduction of the two water molecules, and cleavage is accompanied by their displacement toward the leaving anion, thus offering a qualitative mimicry of the experimental observations.
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Affiliation(s)
- Cyrille Costentin
- Laboratoire d'Electrochimie Moléculaire, Unité Mixte de Recherche Université-CNRS No 7591, Université de Paris 7-Denis Diderot, 2 place Jussieu, 75251 Paris Cedex 05, France
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48
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Direct observation of elementary radical events: low- and high-energy radiation femtochemistry in solutions. Radiat Phys Chem Oxf Engl 1993 2005. [DOI: 10.1016/j.radphyschem.2004.06.014] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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49
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50
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Taylor MS, Barbera J, Schulz CP, Muntean F, McCoy AB, Lineberger WC. Femtosecond dynamics of Cu(H2O)2. J Chem Phys 2005; 122:54310. [PMID: 15740325 DOI: 10.1063/1.1836759] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The ultrafast relaxation dynamics of Cu(H(2)O)(2) is investigated using femtosecond photodetachment-photoionization spectroscopy. In addition, stationary points on the Cu(H(2)O)(2) anion, neutral, and cation potential energy surfaces are characterized by ab initio electronic structure calculations. Electron photodetachment from Cu(-)(H(2)O)(2) initiates the dynamics on the ground-state potential energy surface of neutral Cu(H(2)O)(2). The resulting Cu(H(2)O)(2) complexes experience large-amplitude H(2)O reorientation and dissociation. The time evolution of the Cu(H(2)O)(2) fragmentation products is monitored by time-resolved resonant multiphoton ionization. The parent ion, Cu(+)(H(2)O)(2), is not detected above background levels. The rise to a maximum of the Cu(+) signal from Cu(-)(H(2)O)(2), and the decay of the Cu(+)(H(2)O) signal from Cu(-)(H(2)O)(2) have similar tau approximately 10 ps time dependences to the corresponding signals from Cu(-)(H(2)O), but display clear differences at very short and long times. The experimental observations can be understood in terms of the following picture. Prompt dissociation of H(2)O from nascent Cu(H(2)O)(2) gives rise to a vibrationally excited Cu(H(2)O) complex, which dissociates to Cu+H(2)O due to coupling of H(2)O internal rotation to the dissociation coordinate. This prompt dissociation removes all intra-H(2)O vibrational excitation from the intermediate Cu(H(2)O) fragment, which quenches the long time vibrational predissociation to Cu+H(2)O previously observed in analogous experiments on Cu(-)(H(2)O).
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Affiliation(s)
- Mark S Taylor
- JILA and Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO 80309, USA
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