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Sayed M, Maity DK, Pal H. A comparative photophysical study on the structurally related coumarin 102 and coumarin 153 dyes. J Photochem Photobiol A Chem 2023. [DOI: 10.1016/j.jphotochem.2022.114265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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2
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Lakshmi SN, Bahadur P, Choudhury SD. Fate of Photoinduced Electron Transfer Reactions with Temperature- and pH-Induced Assembly/Disassembly of Star Block Copolymer Micelles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:14125-14134. [PMID: 34797674 DOI: 10.1021/acs.langmuir.1c02383] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The assembly/disassembly of star block copolymers induced by changes in temperature or pH of the medium is anticipated to have interesting implications for hosting/releasing drugs and tuning chemical reactions. This study investigates the possibility of employing the dually sensitive self-assembly of an ethylene oxide-propylene oxide star block copolymer, Tetronic T904, to influence photoinduced electron transfer (ET) reactions, on switching from the assembled state (micelle) when temperature is above the critical micelle temperature (CMT) and pH of the medium is above the pKa of T904 to the dissociated (unimer) state when either the temperature is below the CMT or the polymer is protonated. Steady-state and time-resolved fluorescence techniques have been used to characterize the microenvironments of the reactants in T904 solutions under different temperature and pH conditions and to determine ET rate constants. Interestingly, the bimolecular ET rate constants in both assembled and disassembled states of T904 depict a bell-shaped correlation with the driving force of the reaction, in accordance with Marcus inversion behavior instead of the usual Rehm-Weller behavior seen in conventional solvents. The assembly/disassembly of T904 stimulated by temperature or pH affects the micropolarity in the reactant environment, the magnitude of ET rate constants, and the position of inversion on the exergonicity scale.
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Affiliation(s)
- Suresh Nayana Lakshmi
- Radiation & Photochemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085, India
| | - Pratap Bahadur
- Department of Chemistry, Veer Narmad South Gujarat University, Surat 395007, India
| | - Sharmistha Dutta Choudhury
- Radiation & Photochemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085, India
- Homi Bhabha National Institute, Training School Complex, Anushaktinagar, Mumbai 400094, India
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3
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Saladin M, Maroncelli M. Electron Transfer Kinetics between an Electron-Accepting Ionic Liquid and Coumarin Dyes. J Phys Chem B 2020; 124:11431-11445. [DOI: 10.1021/acs.jpcb.0c06839] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Marissa Saladin
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Mark Maroncelli
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
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4
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Saladin M, Rumble CA, Wagle DV, Baker GA, Maroncelli M. Characterization of a New Electron Donor-Acceptor Dyad in Conventional Solvents and Ionic Liquids. J Phys Chem B 2019; 123:9395-9407. [PMID: 31596593 DOI: 10.1021/acs.jpcb.9b07077] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Ionic liquids are being tested as potential replacements for current electrolytes in energy-related applications. Electron transfer (ET) plays a central role in these applications, making it essential to understand how ET in ionic liquids differs from ET in conventional organic solvents and how these differences affect reaction kinetics. A new intramolecular electron donor-acceptor probe was synthesized by covalently linking the popular photoacceptor coumarin 152 with the donor dimethylaniline to create the dyad "C152-DMA" for potential use in probing dynamical solvent effects in ionic liquids. Molecular dynamics simulations of this dyad show the considerable conformational flexibility of the linker group but over a range of geometries in which the ET rate parameters vary little and should have minimal effect on reaction times >100 ps. Steady-state and time-resolved fluorescence methods show the spectra of C152-DMA to be highly responsive to solvent polarity, with ET rates varying over the range of 108 to 1012 s-1 between nonpolar and high-polarity conventional solvents. The sensitivity to hydrolysis in the presence of acidic impurities limits the dyad's use to ionic liquids of high purity. The results in the few ionic liquids examined here suggest that in addition to solvent polarity, electron transfer in C152-DMA also depends on solvent fluidity or solvation times.
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Affiliation(s)
- Marissa Saladin
- Department of Chemistry , The Pennsylvania State University , University Park , Pennsylvania 16802 , United States
| | - Christopher A Rumble
- Department of Chemistry , The Pennsylvania State University , University Park , Pennsylvania 16802 , United States
| | - Durgesh V Wagle
- Department of Chemistry , University of Missouri - Columbia , Columbia , Missouri 65211 , United States
| | - Gary A Baker
- Department of Chemistry , University of Missouri - Columbia , Columbia , Missouri 65211 , United States
| | - Mark Maroncelli
- Department of Chemistry , The Pennsylvania State University , University Park , Pennsylvania 16802 , United States
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5
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Samanta P, Dutta Choudhury S, Pal H. Kinetics and Energetics of Ultrafast Bimolecular Photoinduced Electron Transfer Reactions in Pluronic-Surfactant Supramolecular Assemblies. J Phys Chem B 2019; 123:5942-5953. [PMID: 31246469 DOI: 10.1021/acs.jpcb.9b04223] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Understanding the kinetics and energetics of photoinduced electron transfer (PET) reactions in constrained media has attracted considerable research interest, as constrained media provide a handle to tune the microenvironments and consequently the mechanisms of PET reactions. In this study, PET reactions between excited 7-aminocoumarin acceptors and ground-state N,N-dimethylaniline (DMAN) donor have been investigated in mixed micellar media composed of triblock copolymer, P123, and anionic surfactant, sodium dodecyl sulfate (SDS), with varying SDS-to-P123 molar ratios (n values). The objective is to elucidate the role of the n values in the rates and energetics of PET reactions over the entire time range from the subpicosecond to the subnanosecond domain, especially in regard to the applicability of the two-dimensional ET (2DET) mechanism. It is observed that by changing the n values, there is a significant change in the hydration characteristics of the SDS-P123 mixed micelles, which in turn changes the kinetics to energetic correlations for the PET reactions. Fluorescence from the excited coumarin acceptors undergoes substantial quenching due to PET from DMAN donor in all of the studied micelles as evidenced from steady-state, subnanosecond time-resolved (TR) and ultrafast (subpicosecond/femtosecond) fluorescence up-conversion measurements. The quenching rate constants (kq), estimated from subnanosecond TR fluorescence studies, and the individual component-wise decay rates (τi-1), estimated from up-conversion measurements, increase gradually with increasing n value, corroborating well with the sequentially increased micropolarity of the mixed micelles. Interestingly, it is observed that the correlations of either kq (from subnanosecond studies) or τi-1 (from femtosecond studies) with the reaction exergonicity (-ΔG°) show the noteworthy Marcus inversion (MI) behavior in a very consistent and similar manner for the entire time window, from subpicoseconds to subnanoseconds. The onset of MI always appears at an exergonicity (-ΔG°MI) much lower than solvent reorganization energy (λs), suggesting the involvement of 2DET mechanism throughout the subpicosecond to subnanosecond time domains. The present results thus provide a comprehensive picture of the kinetics and energetics of the PET reactions in constrained media for the whole time span and unequivocally establish the applicability of 2DET mechanism for the PET reactions in constrained media, eliminating any apprehensions about the effect of time resolution of the subnanosecond setup on the observed Marcus inversion behavior. This is indeed an important finding, providing valuable insights for PET reactions in constrained media, which has not been explored explicitly in any of the previous studies. Observation of MI behavior and the modulations in the PET reactions by simply changing the composition of SDS in the SDS-P123 mixed micelles are noteworthy findings of the present study and are expected to find suitable applications for better utilization and outcome of the PET reactions.
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Affiliation(s)
- Papu Samanta
- Homi Bhabha National Institute , Training School Complex , Anushaktinagar, Mumbai 400094 , India
| | | | - Haridas Pal
- Homi Bhabha National Institute , Training School Complex , Anushaktinagar, Mumbai 400094 , India
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6
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Bimolecular photoinduced electron transfer between 7-methylbenzo[a]pyrene and aromatic amine donors in stationary and static regimes. J Photochem Photobiol A Chem 2019. [DOI: 10.1016/j.jphotochem.2019.03.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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7
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Unveiling the interaction between carbon nanodot and IR light emitting fluorescent dyes inside the confined micellar environment. J Photochem Photobiol A Chem 2019. [DOI: 10.1016/j.jphotochem.2019.03.051] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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8
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Troian-Gautier L, Turlington MD, Wehlin SAM, Maurer AB, Brady MD, Swords WB, Meyer GJ. Halide Photoredox Chemistry. Chem Rev 2019; 119:4628-4683. [PMID: 30854847 DOI: 10.1021/acs.chemrev.8b00732] [Citation(s) in RCA: 94] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Halide photoredox chemistry is of both practical and fundamental interest. Practical applications have largely focused on solar energy conversion with hydrogen gas, through HX splitting, and electrical power generation, in regenerative photoelectrochemical and photovoltaic cells. On a more fundamental level, halide photoredox chemistry provides a unique means to generate and characterize one electron transfer chemistry that is intimately coupled with X-X bond-breaking and -forming reactivity. This review aims to deliver a background on the solution chemistry of I, Br, and Cl that enables readers to understand and utilize the most recent advances in halide photoredox chemistry research. These include reactions initiated through outer-sphere, halide-to-metal, and metal-to-ligand charge-transfer excited states. Kosower's salt, 1-methylpyridinium iodide, provides an early outer-sphere charge-transfer excited state that reports on solvent polarity. A plethora of new inner-sphere complexes based on transition and main group metal halide complexes that show promise for HX splitting are described. Long-lived charge-transfer excited states that undergo redox reactions with one or more halogen species are detailed. The review concludes with some key goals for future research that promise to direct the field of halide photoredox chemistry to even greater heights.
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Affiliation(s)
- Ludovic Troian-Gautier
- Department of Chemistry , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States
| | - Michael D Turlington
- Department of Chemistry , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States
| | - Sara A M Wehlin
- Department of Chemistry , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States
| | - Andrew B Maurer
- Department of Chemistry , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States
| | - Matthew D Brady
- Department of Chemistry , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States
| | - Wesley B Swords
- Department of Chemistry , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States
| | - Gerald J Meyer
- Department of Chemistry , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States
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9
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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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10
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Wu B, Maroncelli M, Castner EW. Photoinduced Bimolecular Electron Transfer in Ionic Liquids. J Am Chem Soc 2017; 139:14568-14585. [DOI: 10.1021/jacs.7b07611] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Boning Wu
- Department of Chemistry
and Chemical Biology, Rutgers, The State University of New Jersey, 610 Taylor Road, Piscataway, New Jersey 08854, United States
| | - Mark Maroncelli
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Edward W. Castner
- Department of Chemistry
and Chemical Biology, Rutgers, The State University of New Jersey, 610 Taylor Road, Piscataway, New Jersey 08854, United States
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11
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Ivanov VL, Lyashkevich SY. Photolysis of 2-mercaptobenzothiazole in the presence of surfactants. HIGH ENERGY CHEMISTRY 2017. [DOI: 10.1134/s0018143917040051] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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12
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Mukherjee P, Das A, Sengupta A, Sen P. Bimolecular Photoinduced Electron Transfer in Static Quenching Regime: Illustration of Marcus Inversion in Micelle. J Phys Chem B 2017; 121:1610-1622. [PMID: 28140599 DOI: 10.1021/acs.jpcb.6b11206] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Ultrafast bimolecular photoinduced electron transfer (PET) between six coumarin dyes and four viologen molecules in the stern layer of sodium dodecyl sulfate micelle have been studied using femtosecond broadband transient absorption spectroscopy and femtosecond fluorescence up-conversion spectroscopy over a broad reaction exergonicity (ΔG0). Emanating the formation of radical cation intermediates of viologen molecules using the transient absorption and the fast decay component of coumarins using the fluorescence up-conversion studies the forward bimolecular electron transfer rate (ket) have been measured with high accuracy. The relationship of ket with ΔG0 found to follow a Marcus type bell-shaped dependence with an inversion at -1.10 eV. In this report, we have studied PET reaction using ultrafast spectroscopy at the quencher concentration where static quenching regime prevails. Moreover, the incompetency of Stern-Volmer experiments in studying ultrafast PET has been revealed. In contrary to previous claims, here we found that the ket is lower for lower lifetime coumarins, indicating that static, nonstationary and stationary regime of quenching have the minimal role to play to in the bimolecular electron transfer process. By far, this report is believed to be the most efficient and immaculate way of approaching Marcus inverted region problem in the case of bimolecular PET and settles the long-lasting debate of whether the same can be observed in micellar systems.
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Affiliation(s)
- Puspal Mukherjee
- Department of Chemistry, Indian Institute of Technology Kanpur , Kanpur 208 016, UP, India
| | - Aritra Das
- Department of Chemistry, Indian Institute of Technology Kanpur , Kanpur 208 016, UP, India
| | - Arunava Sengupta
- Department of Chemistry, Indian Institute of Technology Kanpur , Kanpur 208 016, UP, India
| | - Pratik Sen
- Department of Chemistry, Indian Institute of Technology Kanpur , Kanpur 208 016, UP, India
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13
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Venkatesh Y, Munisamy V, Ramakrishna B, Kumar PH, Mandal H, Bangal PR. Photoinduced bimolecular electron transfer from aromatic amines to pentafluorophenyl porphyrin combined with ultrafast charge recombination persistence with Marcus inverted region. Phys Chem Chem Phys 2017; 19:5658-5673. [PMID: 28168248 DOI: 10.1039/c6cp08520b] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The dynamics of photoinduced bimolecular reductive electron transfer between meso-tetrakis(pentafluorophenyl)porphyrin (H2F20TPP), an acceptor (A), and five aromatic amines (donor (D)) with varying oxidation potentials (aniline (AN), N-methylaniline (MAN), N-ethylaniline (EAN), N,N-dimethylaniline (DMAN) and N,N-diethylaniline (DEAN)) in dichloromethane (DCM) as a solvent as well as in neat donor solvents were investigated by employing nanosecond to femtosecond time-resolved fluorescence spectroscopy and femtosecond time-resolved transient absorption spectroscopy upon S2 excitation of H2F20TPP. Systematic studies of time-resolved fluorescence quenching dependent on the donor concentration in the concentration range of 0.01-2 M and finally in neat donor solvents broadly enabled us to determine the electron transfer dynamics in three regimes of electron transfer: stationary or diffusion-controlled electron transfer, non-stationary electron transfer and intrinsic or ultrafast electron transfer. Depending upon the electron-donating ability of the studied donors, intrinsic electron transfer was found to occur in the time domain of ∼1-9 ps and diffusion-controlled ET dynamics was observed in the time domain of 200-500 ps, whereas the maximum limit of non-stationary electron transfer could be observed in the time domain of 15-50 ps. Femtosecond transient absorption studies together with global and target analysis helped to identify the spectral signature of the (H2F20TPP˙-) radical anion as the product of ET. To the best of our knowledge, this is the first ever evidence that shows the spectra of an anion as the product of ET for any porphyrin-based electron transfer dynamics. However, transient absorption measurements confirm that intrinsic ET occurs in the Qy state, whereas diffusion-controlled ET occurs in the hot Qx as well as in the thermal equilibrium Qx state. The most remarkable fact derived from the measurements of transient absorption was that the rate of the forward electron transfer (CS) is exactly the same as the rate of the backward electron transfer (CR) for all three regimes of ET. The thermodynamic driving force for CR was found to lie in the range of the total reorganization energy for the studied systems and hence falls in the Marcus optimal region, and the CR process is barrierless. The dependence on the driving force of the combination of forward and reverse electron transfer exhibited a bell-shaped curve for all three regimes of electron transfer, even though the rate of intrinsic ET is higher by a factor of ∼102 than that of diffusion-controlled ET. These results unambiguously favour the Marcus theory, in particular the controversial Marcus inverted region, of outer-sphere electron transfer.
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Affiliation(s)
- Yeduru Venkatesh
- Inorganic and Physical Chemistry Division, CSIR-Indian Institute of Chemical Technology, Uppal Road, Tarnaka, Hyderabad 500007, India. and Academy of Scientific and Innovative Research, 2-Rafi Marg, New Delhi 110001, India
| | - Venkatesan Munisamy
- Inorganic and Physical Chemistry Division, CSIR-Indian Institute of Chemical Technology, Uppal Road, Tarnaka, Hyderabad 500007, India.
| | - Bheerappagari Ramakrishna
- Inorganic and Physical Chemistry Division, CSIR-Indian Institute of Chemical Technology, Uppal Road, Tarnaka, Hyderabad 500007, India.
| | - Pippara Hemant Kumar
- Inorganic and Physical Chemistry Division, CSIR-Indian Institute of Chemical Technology, Uppal Road, Tarnaka, Hyderabad 500007, India.
| | - Haraprasad Mandal
- Inorganic and Physical Chemistry Division, CSIR-Indian Institute of Chemical Technology, Uppal Road, Tarnaka, Hyderabad 500007, India. and Academy of Scientific and Innovative Research, 2-Rafi Marg, New Delhi 110001, India
| | - Prakriti Ranjan Bangal
- Inorganic and Physical Chemistry Division, CSIR-Indian Institute of Chemical Technology, Uppal Road, Tarnaka, Hyderabad 500007, India. and Academy of Scientific and Innovative Research, 2-Rafi Marg, New Delhi 110001, India
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14
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Mukherjee P, Sen P. Decoupling diffusion from the bimolecular photoinduced electron transfer reaction: a combined ultrafast spectroscopic and kinetic analysis. Phys Chem Chem Phys 2017; 19:11220-11229. [DOI: 10.1039/c7cp01387f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
We have studied the bimolecular photoinduced electron transfer (PET) reaction between benzophenone (Bp) and DABCO using femtosecond broadband transient absorption spectroscopy in different compositions of acetonitrile/1-butanol binary solvent mixtures.
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Affiliation(s)
- Puspal Mukherjee
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur
- India
| | - Pratik Sen
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur
- India
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15
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Gupta S, Chakraborty A, Sen P. Elucidation of intriguing methanol-dichloromethane binary solvent mixture: Synergistic effect, analytical modeling, NMR and photo-induced electron transfer studies. J Mol Liq 2016. [DOI: 10.1016/j.molliq.2016.08.048] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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16
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Angulo G, Rosspeintner A, Koch M, Vauthey E. Comment on "Observation of the Marcus Inverted Region for Bimolecular Photoinduced Electron-Transfer Reactions in Viscous Media". J Phys Chem B 2016; 120:9800-3. [PMID: 27536949 DOI: 10.1021/acs.jpcb.6b06610] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Gonzalo Angulo
- Institute of Physical Chemistry, Polish Academy of Sciences , 44/52 Kasprzaka, 01-224 Warsaw, Poland
| | - Arnulf Rosspeintner
- Department of Physical Chemistry, University of Geneva , 30 Quai Ernest Ansermet, CH-1211 Geneva, Switzerland
| | - Marius Koch
- Department of Chemistry, Princeton University , 08540 Princeton, New Jersey, United States
| | - Eric Vauthey
- Department of Physical Chemistry, University of Geneva , 30 Quai Ernest Ansermet, CH-1211 Geneva, Switzerland
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17
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Kumbhakar M, Pal H. Reply to "Comment on 'Observation of the Marcus Inverted Region for Bimolecular Photoinduced Electron-Transfer Reactions in Viscous Media'". J Phys Chem B 2016; 120:9804-9. [PMID: 27537065 DOI: 10.1021/acs.jpcb.6b07633] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Manoj Kumbhakar
- Radiation and Photochemistry Division, Bhabha Atomic Research Centre , Trombay, Mumbai 400 085, India
| | - Haridas Pal
- Radiation and Photochemistry Division, Bhabha Atomic Research Centre , Trombay, Mumbai 400 085, India
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18
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Effect of viscosity on photoinduced electron transfer reaction: An observation of the Marcus inverted region in homogeneous solvents. Chem Phys Lett 2016. [DOI: 10.1016/j.cplett.2016.08.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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19
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Sharma A, Enderlein J, Kumbhakar M. Photon Antibunching in Complex Intermolecular Fluorescence Quenching Kinetics. J Phys Chem Lett 2016; 7:3137-3141. [PMID: 27468007 DOI: 10.1021/acs.jpclett.6b01467] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We present a novel fluorescence spectroscopic method, which combines fluorescence antibunching, time-correlated single-photon counting (TCSPC), and steady-state emission spectroscopy, to study chemical reactions at the single molecule level. We exemplify our method on investigating intermolecular fluorescence quenching of Rhodamine110 by aniline. We demonstrate that the combination of measurements of fluorescence antibunching, fluorescence lifetime, and fluorescence steady state intensity, captures the full picture of the complex quenching kinetics, which involves static and dynamics quenching, and which cannot be seen by steady-state or lifetime measurements alone.
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Affiliation(s)
- Arjun Sharma
- Radiation & Photochemistry Division, Bhabha Atomic Research Center , Mumbai 400085, India
| | - Jörg Enderlein
- III Institute of Physics, Georg August University , 37077 Göttingen, Germany
| | - Manoj Kumbhakar
- Radiation & Photochemistry Division, Bhabha Atomic Research Center , Mumbai 400085, India
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20
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Sahu PK, Das SK, Sarkar M. Studies on intramolecular electron transfer reaction in donor–spacer–acceptor systems in room-temperature ionic liquids. J Mol Liq 2016. [DOI: 10.1016/j.molliq.2015.11.027] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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21
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Ivanov VL, Lyashkevich SY. Peculiarities in the photochemical behavior of 1-bromo-2-hydroxynaphthalene in cetylpyridinium chloride micellar solution. HIGH ENERGY CHEMISTRY 2016. [DOI: 10.1134/s0018143915060090] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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22
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Araque JC, Hettige JJ, Margulis CJ. Ionic liquids—Conventional solvent mixtures, structurally different but dynamically similar. J Chem Phys 2015; 143:134505. [DOI: 10.1063/1.4932331] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Juan C. Araque
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242, USA
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23
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Verma P, Pal H. Tuning of electron transfer reactions in pluronic-surfactant supramolecular assemblies. Phys Chem Chem Phys 2015; 17:15400-11. [PMID: 26006183 DOI: 10.1039/c5cp01480h] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Photoinduced electron transfer (ET) reaction between an anionic acceptor, coumarin-343 (C343), and a neutral donor, N,N-dimethylaniline (DMAN), has been investigated in composite supramolecular assemblies (mixed micelles) comprised of a pluronic copolymer (P123: EO20-PO70-EO20 or F88: EO103-PO39-EO103 where EO: ethylene oxide and PO: propylene oxide) and a cationic surfactant (CTAC: cetyltrimethylammonium chloride), following fluorescence quenching studies. Systematic increase in the quenching rates for the studied donor-acceptor system with the increasing CTAC to pluronic molar ratio in the mixed micelles demonstrates a large modulation in the ET rates. The mixed micellar systems in the present cases are formed through the incorporation of the hydrocarbon chains of CTAC into the poly-PO core of the pluronic micelles whereby the cationic head groups of CTAC are placed at the periphery of the micellar core, protruded into the hydrated poly-EO corona region, leading to the formation of a positively charged layer deep inside these mixed micelles. Thus, the anionic C343 dye, initially dissolved at the micelle-water interface, experiences a gradually increasing electrostatic attraction and is therefore systematically dragged deeper inside the micellar corona, as the CTAC composition is increased in the mixed micellar systems. Consequently, the ET rate of the C343-DMAN pair undergoes a large enhancement in the studied mixed micellar systems with the increasing CTAC to pluronic molar ratio. The present strategy of modulating ET reactions using such composite supramolecular assemblies can find applications in areas where bimolecular ET is an integral reaction step.
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Affiliation(s)
- Poonam Verma
- Radioanalytical Chemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085, India.
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