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Mondal J, Maji D, Mitra S, Biswas R. Temperature-Dependent Dielectric Relaxation Measurements of (Betaine + Urea + Water) Deep Eutectic Solvent in Hz-GHz Frequency Window: Microscopic Insights into Constituent Contributions and Relaxation Mechanisms. J Phys Chem B 2024; 128:6567-6580. [PMID: 38949428 DOI: 10.1021/acs.jpcb.4c02784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/02/2024]
Abstract
A combined experimental and simulation study of dielectric relaxation (DR) of a deep eutectic solvent (DES) composed of betaine, urea, and water with the composition [Betaine:Urea:Water = 11.7:12:1 (weight ratio) and 9:18:5 (molar ratio)] was performed to explore and understand the interaction and dynamics of this system. Temperature-dependent (303 ≤ T/K ≤ 343) measurements were performed over 9 decades of frequency, combining three different measurement setups. Measured DR, comprising four distinct steps with relaxation times spreading over a few picoseconds to several nanoseconds, was found to agree well with simulations. The simulated total DR spectra, upon dissection into three self (intraspecies) and three cross (interspecies) interaction contributions, revealed that the betaine-betaine self-term dominated (∼65%) the relaxation, while the urea-urea and water-water interactions contributed only ∼7% and ∼1%, respectively. The cross-terms (betaine-urea, betaine-water, and urea-water) together accounted for <30% of the total DR. The slowest DR component with a time constant of ∼1-10 ns derived dominant contribution from betaine-betaine interactions, where betaine-water and urea-water interactions also contributed. The subnanosecond (0.1-0.6 ns) time scale originated from all interactions except betaine-water interaction. An extensive interaction of water with betaine and urea severely reduced the average number of water-water H-bonds (∼0.7) and heavily decreased the static dielectric constant of water in this DES (εs ∼ 2). Furthermore, simulated first rank collective single particle reorientational relaxations (C1(t)) and the structural H-bond fluctuation dynamics (CHB (t)) exhibited multiexponential kinetics with time scales that corresponded well with those found both in the simulated and measured DR.
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Affiliation(s)
- Jayanta Mondal
- Department of Chemical and Biological Sciences, S. N. Bose National Centre for Basic Sciences, JD Block, Sector III, Salt Lake, Kolkata 700106, India
| | - Dhrubajyoti Maji
- Department of Chemical and Biological Sciences, S. N. Bose National Centre for Basic Sciences, JD Block, Sector III, Salt Lake, Kolkata 700106, India
| | - Sudipta Mitra
- Department of Chemical and Biological Sciences, S. N. Bose National Centre for Basic Sciences, JD Block, Sector III, Salt Lake, Kolkata 700106, India
| | - Ranjit Biswas
- Department of Chemical and Biological Sciences, S. N. Bose National Centre for Basic Sciences, JD Block, Sector III, Salt Lake, Kolkata 700106, India
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Nomura S, Fujii K, Sugihara H, Endo T, Kimura Y. Anion Effect on the Excited-State Intramolecular Proton Transfer of 4'- N, N-Diethylamino-3-hydroxyflavone in Ionic Liquids. J Phys Chem B 2024; 128:6549-6559. [PMID: 38935614 DOI: 10.1021/acs.jpcb.4c02573] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/29/2024]
Abstract
The excited-state intramolecular proton transfer (ESIPT) reaction of 4'-N,N,-diethylamino-3-hydroxyflavone (C2HF) was studied using time-resolved fluorescence measurements in ionic liquids (ILs) of various anions with a fixed cation (1-ethyl-3-methylimidazolium [C2mim]+). C2HF showed an ESIPT reaction from the normal excited state (N*; keto form) to the tautomer excited state (T*; enol form) where both states are emissive. The ESIPT rate and yield were obtained by analyzing the time-resolved fluorescence spectra measured using the optical Kerr gate method. Both the ESIPT rate and yield decreased with increasing hydrogen-bond accepting ability of the anion. According to density functional theory calculations, the complex formation energy between C2HF and the anion became significantly negative with increasing the hydrogen-bond accepting ability of anion. The pseudoequilibrium constant between N* and T* ([T*]/[N*]) in the electronic excited state decreased with increasing hydrogen-bond accepting ability of the anion, while it increased with increasing the alkyl-chain length of alkyl sulfonate. The excitation wavelength dependence of the ESIPT rate and yield was studied for C2HF in [C2mim][C6H13SO3]. The ESIPT yield decreased by nearly a factor of 2 with increasing excitation wavelength from 360 to 425 nm, although the change in the ESIPT rate was small. The solvation heterogeneity due to the alkyl chain in the anion was considered to be the reason for the excitation wavelength dependence.
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Affiliation(s)
- Shohnosuke Nomura
- Department of Applied Chemistry, Graduate School of Science and Engineering, Doshisha University, 2-1, Tatara Miyakodani, Kyotanabe-City, Kyoto 610-0321, Japan
| | - Kaori Fujii
- National Institute of Advanced Industrial Science and Technology, 1-1-1, Higashi, Tsukuba, Ibaraki 305-8565, Japan
| | - Hiroaki Sugihara
- Division of Molecular Chemistry and Biochemistry, Faculty of Science and Engineering, Doshisha University, 2-1, Tatara Miyakodani, Kyotanabe-City, Kyoto 610-0321, Japan
| | - Takatsugu Endo
- Division of Molecular Chemistry and Biochemistry, Faculty of Science and Engineering, Doshisha University, 2-1, Tatara Miyakodani, Kyotanabe-City, Kyoto 610-0321, Japan
| | - Yoshifumi Kimura
- Department of Applied Chemistry, Graduate School of Science and Engineering, Doshisha University, 2-1, Tatara Miyakodani, Kyotanabe-City, Kyoto 610-0321, Japan
- Division of Molecular Chemistry and Biochemistry, Faculty of Science and Engineering, Doshisha University, 2-1, Tatara Miyakodani, Kyotanabe-City, Kyoto 610-0321, Japan
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Srivastava S, Sinha S, Bhattacharjee S, Seth D. Solute dynamics of a hydrophobic molecule in a menthol-thymol based type-V deep eutectic solvent: effect of composition of the components. Phys Chem Chem Phys 2024; 26:12638-12651. [PMID: 38597695 DOI: 10.1039/d4cp00088a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
Type-V deep eutectic solvents (DESs) are a newly emerging unique class of solvents obtained by physical mixing and heating of non-ionic components. These solvents show deviation from the thermodynamic ideality. Compared to type-I to IV DESs, type-V DESs are less explored and their physical chemistry is in its nascent stage. In this work, we have chosen a type-V DES based on menthol-thymol (MT) for our working media. Solvent and rotational dynamics were studied with varying temperature using a well-known solvatochromic probe, Coumarin 153 (C153). We prepared the MT-based DES using a reported procedure at three molar ratios: 1 : 1 (M1T1), 1 : 1.5 (M1T1.5), and 2 : 1 (M2T1) of menthol (M) and thymol (T). Time-resolved emission spectra (TRES) were constructed with varying temperature. Utilizing TRES, the decay of the solvent correlation function (C(t)) was plotted. We have correlated the solvent relaxation time in these DESs as a function of viscosity. The time-resolved anisotropy decays were also collected to perceive the rotational relaxation dynamics of C153 as a function of temperature. The decay of solvent relaxation was found to be bi-exponential, and the average solvation time (〈τs〉) in M2T1 was found to be longer than those of M1T1.5 and M1T1. The rotational reorientation times (〈τrot〉) also follow the same trend. We have analysed the rotational dynamics of C153 in type-V DESs employing the Stokes-Einstein-Debye (SED) hydrodynamic model. The rotational dynamics in DESs demonstrate a good correlation with the SED model with a little deviation. In MT-based DESs, the solute's rotational relaxation times approach hydrodynamic stick boundary condition at low viscosity (or at high temperatures) for all molar compositions. Using the Arrhenius-type equations, we have correlated the activation energies for the rotational motion of C153, along with the viscous flow and non-radiative pathways for all the DESs.
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Affiliation(s)
- Sagar Srivastava
- Department of Chemistry, Indian Institute of Technology Patna, Patna 801103, Bihar, India.
| | - Sapana Sinha
- Department of Chemistry, Indian Institute of Technology Patna, Patna 801103, Bihar, India.
| | - Sanyukta Bhattacharjee
- Department of Chemistry, Indian Institute of Technology Patna, Patna 801103, Bihar, India.
| | - Debabrata Seth
- Department of Chemistry, Indian Institute of Technology Patna, Patna 801103, Bihar, India.
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Mukherjee K, Palchowdhury S, Maroncelli M. Do Electrostatics Control the Diffusive Dynamics of Solitary Water? NMR and MD Studies of Water Translation and Rotation in Dipolar and Ionic Solvents. J Phys Chem B 2024; 128:3689-3706. [PMID: 38588535 DOI: 10.1021/acs.jpcb.3c08300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/10/2024]
Abstract
NMR-based measurements of the diffusion coefficients and rotation times of solitary water and benzene at 300 K are reported in a diverse collection of 13 conventional organic solvents and 10 imidazolium ionic liquids. Proton chemical shifts of water are found to be correlated to water OH-stretching frequencies, confirming the importance of electrostatic interactions in these shifts. However, the influence of magnetic interactions in aromatic solvents renders chemical shifts a less reliable indicator of electrostatics. Diffusion coefficients (DB) and rotational correlation times (τB) of benzene in the solvents examined are accurately described as functions of viscosity (η) by DB ∝ η-0.81 and τB ∝ η0.64. Literature values of DB and τB in alkane and normal alcohols, which were not included among the solvents studied here, are systematically faster than predicted by these correlations, indicating that factors beyond solvent viscosity play a role in determining the friction on benzene. In contrast to benzene, water diffusion and rotation are poorly described in terms of viscosity alone, even in the dipolar and ionic solvents measured here. The present data and the substantial literature data already available on dilute water diffusion show a systematic dependence of DW on solvent polarity among isoviscous solvents. The aspect of solvent polarity most relevant to water dynamics is the ability of a solvent to accept hydrogen bonds from water, as conveniently quantified by the frequency of water's OH stretching band, ΔνOH. The friction on translation, ζtr = kBT/DW, and rotation, ζrot = kBTτW, are both well correlated by functions of the form ζ(η, ΔνOH) = a1ηa2 exp (a3ΔνOH), where the ai are adjustable parameters. Molecular dynamics simulations reveal a strong coupling between electrostatic and nonelectrostatic water-solvent interactions, which makes it impossible to dissect the friction on water into additive dielectric and hydrodynamic components. Simulations also provide a tentative explanation for the unusual form of the correlating function ζ(η, ΔνOH), at least in the case of ζrot.
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Affiliation(s)
- Kallol Mukherjee
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Sourav Palchowdhury
- 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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Sardar R, Das S, Banik R, Bhunia S, Ghosh S. Exploration of the impact of graphene oxide, acetylenic gemini, and CTAT on the photophysical and aggregation properties of dipolar coumarin 153. Phys Chem Chem Phys 2024; 26:8900-8918. [PMID: 38426553 DOI: 10.1039/d3cp05361j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2024]
Abstract
Advanced spectroscopic techniques have been utilized to study the interaction between the laser dye coumarin 153 (C153) and graphene oxide (GO) nanoparticles. GO was synthesized using a modified Hummers' method and characterized by UV-vis spectroscopy, Raman laser spectroscopy, FTIR-ATR spectroscopy, FESEM, HR-TEM, and XRD techniques. The GO@C153 composite was formed by mixing two aqueous solutions of GO and C153 due to their strong interaction through stacking and hydrophobic interactions. In this case, GO acts as an effective fluorescence quencher for C153 molecules, which undergo H-type aggregation in the presence of GO. The Stern-Volmer equation and time-dependent fluorescence studies were utilized to analyse the mechanism of fluorescence quenching. According to the findings, both static and dynamic quenching processes are responsible for the reduction in fluorescence intensity. The effect of surfactants (both cetyltrimethylammonium p-toluenesulfonate (CTAT) and synthesized N,N'-dihexadecyl-N,N,N',N'-tetramethyl-N,N'-but-2-ynediyl-di-ammonium chloride (16-4-16)) on the aggregation and photophysical properties of the dye was investigated using surface tensiometry, conductometry, UV-vis absorption spectroscopy, steady-state fluorescence measurements, DLS, and time-dependent fluorescence spectroscopy. Surfactants change the microenvironment of the C153 dye, leading to spectrum shifting and a higher quantum yield, which causes a rapid rise in fluorescence intensity in the micellar medium. It has been noted that in a micellar medium rather than in an aqueous one, the luminous intramolecular charge transfer (ICT) state of C153 stabilises. Lastly, we investigated the photophysical behavior of the GO-C153-micelle ternary system and discovered that, in the presence of a micellar medium, the quenched and blue-shifted (H-type aggregation) fluorescence peak of C153 (in the presence of GO) began to intensify once more. The main goal of this work is to create an effective and fairly cost powerful fluorescence sensor. Additionally, the ternary system (GO-C153-micelle) analytical idea can be employed to identify the onset of micelle formation. In wastewater treatment analysis, the GO-C153-surfactant ternary system concept can also be used to regenerate the adsorbent (in this case, GO) from dye molecules by allowing the dye molecules to exit the adsorbent and enter the micellar medium.
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Affiliation(s)
- Raju Sardar
- Centre for Surface Science, Physical Chemistry Section, Department of Chemistry, Jadavpur University, Kolkata 700032, India.
| | - Sourav Das
- Centre for Surface Science, Physical Chemistry Section, Department of Chemistry, Jadavpur University, Kolkata 700032, India.
| | - Rajesh Banik
- Centre for Surface Science, Physical Chemistry Section, Department of Chemistry, Jadavpur University, Kolkata 700032, India.
| | - Sayani Bhunia
- Centre for Surface Science, Physical Chemistry Section, Department of Chemistry, Jadavpur University, Kolkata 700032, India.
| | - Soumen Ghosh
- Centre for Surface Science, Physical Chemistry Section, Department of Chemistry, Jadavpur University, Kolkata 700032, India.
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Wega J, Vauthey E. Bimolecular photoinduced symmetry-breaking charge separation of perylene in solution. Photochem Photobiol Sci 2024; 23:93-105. [PMID: 38133700 PMCID: PMC10834668 DOI: 10.1007/s43630-023-00504-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 11/05/2023] [Indexed: 12/23/2023]
Abstract
Photoinduced symmetry-breaking charge separation (SB-CS) results in the generation of charge carriers through electron transfer between two identical molecules, after photoexcitation of one of them. It is usually studied in systems where the two reacting moieties are covalently linked. Examples of photoinduced bimolecular SB-CS with organic molecules yielding free ions remain scarce due to solubility or aggregation issues at the high concentrations needed to study this diffusion-assisted process. Here we investigate the excited-state dynamics of perylene (Pe) at high concentrations in solvents of varying polarity. Transient absorption spectroscopy on the subnanosecond to microsecond timescales reveal that self-quenching of Pe in the lowest singlet excited state leads to excimer formation in all solvents used. Additionally, bimolecular SB-CS, resulting in the generation of free ions, occurs concurrently to excimer formation in polar media, with a relative efficiency that increases with the polarity of the solvent. Moreover, we show that SB-CS is most efficient in room-temperature ionic liquids due to a charge-shielding effect leading to a larger escape of ions and due to the high viscosity that disfavours excimer formation.
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Affiliation(s)
- Johannes Wega
- Department of Physical Chemistry, University of Geneva, Quai Ernest Ansermet 30, 1205, Geneva, Switzerland
| | - Eric Vauthey
- Department of Physical Chemistry, University of Geneva, Quai Ernest Ansermet 30, 1205, Geneva, Switzerland.
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Fujii K, Kimura Y. Solvent Role of Ionic Liquids in Fundamental Chemical Reaction Dynamics Analyzed by Time-Resolved Spectroscopy. CHEM REC 2023; 23:e202200242. [PMID: 36634996 DOI: 10.1002/tcr.202200242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 12/24/2022] [Indexed: 01/14/2023]
Abstract
Ionic liquids (ILs), which are used as solvents for chemical reactions, are different from conventional organic solvents owing to their designability. Physicochemical parameters of the ILs, such as polarity and viscosity, that affect chemical equilibria and reaction kinetics can be tuned by changing the combination of anions and cations or by varying the lengths of the alkyl chains present in the cations. We were interested in knowing how these physicochemical parameters affect fundamental chemical reactions in ILs. Therefore, in this personal account, we investigate our recent work on two different photochemical reactions in ILs, namely excited-state intramolecular proton transfer of hydroxyflavone and photodissociation of aminodisulfide, using time-resolved spectroscopic techniques. Interestingly, the roles of the ILs in these chemical reactions are quite different. The effect of the cationic species of the ILs (i. e., the head groups and number of alkyl carbons) on the solvation environment upon photoexcitation and reaction rate are discussed.
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Affiliation(s)
- Kaori Fujii
- Faculty of Science and Engineering, Doshisha University, Kyotanabe-city, Kyoto 610-0321, Japan
| | - Yoshifumi Kimura
- Graduate School of Science and Engineering, Faculty of Science and Engineering, Doshisha University, Kyotanabe-city, Kyoto 610-0321, Japan
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Takamuku T, Nishiyama D, Kawano M, Miannay FA, Idrissi A. Solvation structure and dynamics of coumarin 153 in an imidazolium-based ionic liquid with chloroform, benzene, and propylene carbonate. Phys Chem Chem Phys 2023; 25:9868-9880. [PMID: 36946188 DOI: 10.1039/d2cp05858h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2023]
Abstract
In order to determine the self-diffusion coefficients D of all the species in the solutions at 298.2 K, 1H and 19F NMR diffusion ordered spectroscopy (DOSY) has been conducted on coumarin 153 (C153) in binary mixed solvents of an imidazolium-based ionic liquid (IL), 1-dodecyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide (C12mimTFSA), with three molecular liquids (MLs) of chloroform (CL), benzene (BZ), and propylene carbonate (PC) as a function of ML mole fraction xML. Below xML ≈ 0.8, the D values of each species do not significantly depend on the MLs. However, above this mole fraction, the diffusion of C153 becomes smoother in the order of BZ ≈ CL > PC systems. The interactions among C153, C12mim+, TFSA-, and ML molecules have been investigated using infrared (IR) and 1H and 13C NMR spectroscopic techniques. The relations of the diffusion of the species with the interactions among them have been discussed on the molecular scale. In the IL solution, the C153 carbonyl oxygen atom is hydrogen-bonded with the imidazolium ring C2-H atom of C12mim+. C12mim+ also forms an ion pair with TFSA-. Thus, C153, C12mim+, and TFSA- cooperatively move in the CL and BZ solutions at a lower ML content, xML < ∼0.8. On the other hand, at a higher ML content, xML > ∼0.8, the C153 molecule diffuses with CL and BZ molecules because of the hydrogen bonding between the C153 carbonyl O atom and the CL H atom and the π-π interaction between the C153 and BZ ring planes, respectively. For the PC system, the change in the relative self-diffusion coefficients of each species with increasing xML differs from those for the CL and BZ systems because of both hydrogen bonding donor H and acceptor O atoms of PC for C153, the IL cation and anion, and PC themselves.
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Affiliation(s)
- Toshiyuki Takamuku
- Department of Chemistry and Applied Chemistry, Faculty of Science and Engineering, Saga University, Honjo-machi, Saga 840-8502, Japan.
| | - Daiki Nishiyama
- Functional Biomolecular Science, Graduate School of Advanced Health Sciences, Saga University, Honjo-machi, Saga 840-8502, Japan
| | - Masahiro Kawano
- Department of Chemistry and Applied Chemistry, Graduate School of Science and Engineering, Saga University, Honjo-machi, Saga 840-8502, Japan
| | - François-Alexandre Miannay
- Laboratoire de Spectrochimie Infrarouge et Raman, UMR CNRS A8516, Université de Lille, Science et Technologies, 59655 Villeneuve d'Ascq, France
| | - Abdenacer Idrissi
- Laboratoire de Spectrochimie Infrarouge et Raman, UMR CNRS A8516, Université de Lille, Science et Technologies, 59655 Villeneuve d'Ascq, France
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Das A, Bhattacharyya S, Rohwer EJ, Gazzetto M, Cannizzo A, Rothlisberger U, Feurer T. Control of Excited State Charge Transfer Dynamics of DMABN in Deep Eutectic Solvent: Involvement of the Partially Twisted Intermediate State. J Mol Liq 2023. [DOI: 10.1016/j.molliq.2023.121551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/05/2023]
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Temperature-dependent ultrafast solvation dynamics of choline chloride-based deep eutectic solvent (DES) and hydroxyl functionalized room temperature ionic liquids (RTILs): Exploring the difference in solvent response between DES and RTILs. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.120545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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11
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Dynamics of a PEG based polymer gel Electrolyte: A combined frequency dependent dielectric relaxation and Time-resolved fluorescence spectroscopic study. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.119491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Hassan MR, Colon BA, Russell J, Calhoun TR. Small Molecule Sorting: A Fluorescence Study of Microemulsions. J Phys Chem B 2022; 126:4990-4998. [PMID: 35759793 DOI: 10.1021/acs.jpcb.2c02774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The application of microemulsions to a wide range of industries relies on their ability to solubilize small molecules with vastly different structures. Herein, we use multiple fluorescence techniques to probe ionic (rhodamine 6g, r6g), polar (coumarin 153, c153), nonpolar (diphenylanthracene, DPA), and amphiphilic (laurdan) small molecules in a nonionic, bicontinuous microemulsion of varying hydration. All fluorophores investigated were found to associate with the surfactant region despite their different structures and properties. The hydration of the surfactant layer was found to increase linearly with water addition, but while this initially increases the fluidity of the surfactant layer, fluorescence anisotropy of c153 and r6g indicates a stiffening of the surfactant at water content >60%. This stiffening of the surfactant layer at higher water content correlates with a morphological change in the microemulsion from a bicontinuous structure to droplets. In contrast, the nonpolar DPA shows a change in partitioning as hydration changes, increasing its association with the oil domain. Overall, these studies elucidate not only the capability of these microemulsions to host a range of small molecules in the surfactant layer with tunable position but also the ability to probe the driving force of bulk structural changes in these heterogeneous fluids.
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Affiliation(s)
- Muhammad Redwan Hassan
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Brandon A Colon
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - James Russell
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Tessa R Calhoun
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
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Ornaghi HL, Neves RM, Monticeli FM, Agnol LD. Dynamic mechanical and thermogravimetric properties of synthetized polyurethanes. Polym Bull (Berl) 2022. [DOI: 10.1007/s00289-022-04257-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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14
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Dinda S, Sil A, Das A, Tarif E, Biswas R. Does urea modify microheterogeneous nature of ionic amide deep eutectics? Clues from non-reactive and reactive solute-centered dynamics. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2021.118126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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15
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De CK, Ghosh A, Mandal PK. Hydrophobicity-Dependent Heterogeneous Nanoaggregates and Fluorescence Dynamics in Room-Temperature Ionic Liquids. J Phys Chem B 2022; 126:1551-1557. [PMID: 35166544 DOI: 10.1021/acs.jpcb.1c08598] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The hydrophobicity of room-temperature ionic liquids (RTILs) has been shown to have a very significant effect on the optical and structural properties of and in RTILs. The average excited state lifetime of neat RTILs has been shown to be increasing with increasing hydrophobicity of the RTILs. By employing pico-nanosecond-based fluorescence anisotropy decay, the volume of the nanoaggregates in neat RTILs have been calculated. The volume of these nanoaggregates have been shown to be decreasing with increase in hydrophobicity of the RTILs. Thus, hydrophobicity has been shown to have an important role, i.e., hydrophobicity can be used as a handle to tune the properties of RTILs as designer solvents. Moreover, the excited-state lifetime of red-emitting fluorophores, i.e., whose fluorescence emission is not perturbed by the inherent emission of RTILs, has been shown to increase with the increasing hydrophobicity of the RTILs. Highly hydrophobic RTILs have been shown to exhibit positive deviation and highly hydrophilic RTIL has been shown to exhibit negative deviation from the linear correlation between average solvation time (τs) versus viscosity/temperature (η/T).
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Smortsova Y, Miannay FA, Gustavsson T, Sauvage F, Ingrosso F, Kalugin O, Idrissi A. Interrogating the mechanism of the solvation dynamics in BmimBF4/PC mixtures: A cooperative study employing time-resolved fluorescence and molecular dynamics. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.117163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Layek S, Banerjee P, Sarkar N. An insight into the dissolution of cellulose in 1-butyl-3-methylimidazolium chloride-DMSO binary Mixture: Exploring the dynamics of rhodamine 6G and fluorescein. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.116817] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Solvation, rotational dynamics, photophysical properties study of aromatic asymmetric di-ketones: An experimental and theoretical approach. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.116456] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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LaRocca MM, Baker GA, Heitz MP. Assessing rotation and solvation dynamics in ethaline deep eutectic solvent and its solutions with methanol. J Chem Phys 2021; 155:034505. [PMID: 34293899 DOI: 10.1063/5.0056653] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Steady-state and time-resolved fluorescence were used to investigate the solvation of coumarin 153 (C153) and coumarin 343 (C343) in methanol + ethaline binary solutions, a deep eutectic solvent composed of a 1:2 molar ratio choline chloride + ethylene glycol. In addition, time-resolved anisotropy decays were used to determine the solute's rotational reorientation time as a function of viscosity. Measurements were made in solutions covering the entire range of mole fraction. Viscosity measurements were used to characterize the bulk solvent properties, and as expected, addition of methanol resulted in an decreased viscosity, showing an exponential decrease with mole fraction, up to ∼50-fold at xMeOH = 1.0. Probe rotational reorientation times were found to be biexponential at xMeOH < 0.3 for C153 and xMeOH < 0.5 for C343 and monoexponential at richer methanol content. In proportion to viscosity, C153 and C343 average rotation times decreased ∼30-fold from xMeOH = 0 to 0.9 and showed a power law dependence of ∼η0.85. Rotation times approached the stick boundary limit on dilution with methanol. Time-resolved Stokes shifts quantified the solvation dynamics and were nearly single exponential for C153 but were clearly biexponential for C343. Solvation times also tracked with viscosity according to a power law dependence, with exponents of 0.3 and 0.4 for C153 and C343, respectively. The dilution effect of methanol was not linear in proportion to the viscosity change and alone cannot account for the change in solvation. Dilution also showed a different correlation to solvation than did temperature variations to govern the viscosity change.
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Affiliation(s)
- Mary M LaRocca
- Department of Chemistry and Biochemistry, SUNY Brockport, Brockport, New York 14420, USA
| | - Gary A Baker
- Department of Chemistry, University of Missouri-Columbia, Columbia, Missouri 65211, USA
| | - Mark P Heitz
- Department of Chemistry and Biochemistry, SUNY Brockport, Brockport, New York 14420, USA
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21
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Atamas N, Yablochkova K, Lazarenko M. Microscopic dynamics and the dynamic heterogeneity of motion of polar molecules in ionic liquids. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.115900] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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22
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Miyabayashi H, Fujii K, Watanabe T, Matano Y, Endo T, Kimura Y. Excited-State Intramolecular Proton Transfer Reaction and Ground-State Hole Dynamics of 4'- N, N-Dialkylamino-3-hydroxyflavone in Ionic Liquids Studied by Transient Absorption Spectroscopy. J Phys Chem B 2021; 125:5373-5386. [PMID: 34003004 DOI: 10.1021/acs.jpcb.1c02360] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The excited-state intramolecular proton transfer (ESIPT) of 4'-N,N-dialkylamino-3-hydroxyflavone (CnHF) having different alkyl chain lengths (ethyl, butyl, and octyl chains) was investigated in ionic liquids (ILs) by steady-state fluorescence and transient absorption spectroscopy. Upon photoexcitation, CnHF underwent ESIPT from the normal form to the tautomer form, and dual emissions from both states were detected. For C4HF and C8HF, the tautomerization yields determined from the fluorescence intensity ratios increased with the increasing number of alkyl chain carbon atoms in the cation and on reducing the excitation wavelength as reported for C2HF [K. Suda et al., J. Phys. Chem. B. 117, 12567 (2013)]. The transient absorption spectra of CnHF were measured at excitation wavelengths of 360, 400, and 450 nm. The ESIPT rate determined from the induced emission of the tautomer was correlated with the tautomerization yield for C2HF and C4HF. In addition, the recovery of the ground-state bleach was found to be strongly dependent on the excitation wavelength. This result indicates that the solvated state of the molecule before photoexcitation is dependent on the excitation wavelengths. The time constant for the ground-state relaxation was slower than that for the excited state.
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Affiliation(s)
- Hanamichi Miyabayashi
- Department of Applied Chemistry, Graduate School of Science and Engineering, Doshisha University, Kyotanabe 610-0321, Kyoto, Japan
| | - Kaori Fujii
- Department of Applied Chemistry, Graduate School of Science and Engineering, Doshisha University, Kyotanabe 610-0321, Kyoto, Japan
| | - Takumi Watanabe
- Department of Chemistry, Graduate School of Science and Technology, Niigata University, Nishi-ku, Niigata 950-2181, Japan
| | - Yoshihiro Matano
- Department of Chemistry, Graduate School of Science and Technology, Niigata University, Nishi-ku, Niigata 950-2181, Japan
| | - Takatsugu Endo
- Department of Molecular Chemistry and Biochemistry, Faculty of Science and Engineering, Doshisha University, Kyotanabe 610-0321, Kyoto, Japan
| | - Yoshifumi Kimura
- Department of Applied Chemistry, Graduate School of Science and Engineering, Doshisha University, Kyotanabe 610-0321, Kyoto, Japan
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23
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Fujii K, Nakano H, Sato H, Kimura Y. Experimental observation of the unique solvation process along multiple solvation coordinates of photodissociated products. Phys Chem Chem Phys 2021; 23:4569-4579. [PMID: 33616585 DOI: 10.1039/d0cp06588a] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Chemical reaction dynamics in solution are closely related to solvation dynamics, and understanding solvent responses remains a crucial issue in chemistry and chemical biology. In this study, we experimentally and computationally investigated the solvation dynamics along different solvation coordinates of the same molecule: the electronically excited state and ground state of the p-aminophenylthiyl radical generated by the photodissociation of bis(p-aminophenyl)disulfide. Time profiles of the peak shifts from the transient absorption and emission spectra after photodissociation were extracted to discuss the solvent reorganization process in various ionic liquids (ILs) with different viscosities. The absorption peak position of the radical followed common solvation dynamics, shifting to a lower energy with time due to reorganization of the surrounding solvent molecules in response to the charge redistribution and molecular volume change caused by photodissociation. On the other hand, the emission band of the radical did not show a meaningful spectral shift with time. It was also found that the solvation time in the ground state was not strongly dependent on the solvent viscosity. These experimental results deviate from the conventional dynamic Stokes shift theory. To discuss the experimental results, non-equilibrium molecular dynamics simulations were conducted. The spectral shift obtained by MD simulations indicated the existence of a large solvation energy change and solvation dynamics around the radical after the photodissociation. On the other hand, the electronic excitation of the radical brought about a relatively smaller solvation energy change, especially at the long delay time after the photodissociation. These differences might be one of the reasons for the unique experimentally observed solvation dynamics.
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Affiliation(s)
- Kaori Fujii
- Department of Applied Chemistry, Doshisha University, Kyotanabe, Kyoto 610-0321, Japan.
| | - Hiroshi Nakano
- Department of Molecular Engineering, Kyoto University, Kyoto Daigaku Katsura, Kyoto 615-8510, Japan
| | - Hirofumi Sato
- Department of Molecular Engineering, Kyoto University, Kyoto Daigaku Katsura, Kyoto 615-8510, Japan
| | - Yoshifumi Kimura
- Department of Applied Chemistry, Doshisha University, Kyotanabe, Kyoto 610-0321, Japan.
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24
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Das N, Sen P. Dynamic heterogeneity and viscosity decoupling: origin and analytical prediction. Phys Chem Chem Phys 2021; 23:15749-15757. [PMID: 34286756 DOI: 10.1039/d1cp01804c] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The molecular-level structure and dynamics decide the functionality of solvent media. Therefore, a significant amount of effort is being dedicated continually over time in understanding their structural and dynamical features. One intriguing aspect of solvent structure and dynamics is heterogeneity. In these systems, the dynamics follow , where p is the measure of viscosity decoupling. We analytically predicted that in such cases, the Stokes-Einstein relationship is modified to due to microdomain formation, and the second term on the right-hand side leads to viscosity decoupling. We validated our prediction by estimating the p values of a few solvents, and they matched well with the literature. Overall, we believe that our approach gives a simple yet unique physical picture to help us understand the heterogeneity of solvent media.
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Affiliation(s)
- Nilimesh Das
- 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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25
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Narita T, Fujii K, Endo T, Kimura Y. Effect of cation alkyl chain length on photo-luminescence dynamics of ionic liquids containing dicyanoaurate(I) anion. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.114212] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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26
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Chen X, Cui Y, Gobeze HB, Kuroda DG. Assessing the Location of Ionic and Molecular Solutes in a Molecularly Heterogeneous and Nonionic Deep Eutectic Solvent. J Phys Chem B 2020; 124:4762-4773. [PMID: 32421342 PMCID: PMC7304071 DOI: 10.1021/acs.jpcb.0c02482] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
![]()
Deep
eutectic solvents (DES) are emerging sustainable designer
solvents viewed as greener and better alternatives to ionic liquids.
Nonionic DESs possess unique properties such as viscosity and hydrophobicity
that make them desirable in microextraction applications such as oil-spill
remediation. This work builds upon a nonionic DES, NMA–LA DES,
previously designed by our group. The NMA–LA DES presents a
rich nanoscopic morphology that could be used to allocate solutes
of different polarities. In this work, the possibility of solvating
different solutes within the nanoscopically heterogeneous molecular
structure of the NMA–LA DES is investigated using ionic and
molecular solutes. In particular, the localized vibrational transitions
in these solutes are used as reporters of the DES molecular structure
via vibrational spectroscopy. The FTIR and 2DIR data suggest that
the ionic solute is confined in a polar and continuous domain formed
by NMA, clearly sensing the direct effect of the change in NMA concentration.
In the case of the molecular nonionic and polar solute, the data indicates
that the solute resides in the interface between the polar and nonpolar
domains. Finally, the results for the nonpolar and nonionic solute
(W(CO)6) are unexpected and less conclusive. Contrary to
its polarity, the data suggest that the W(CO)6 resides
within the NMA polar domain of the DES, probably by inducing a domain
restructuring in the solvent. However, the data are not conclusive
enough to discard the possibility that the restructuring comprises
not only the polar domain but also the interface. Overall, our results
demonstrate that the NMA–LA DES has nanoscopic domains with
affinity to particular molecular properties, such as polarity. Thus,
the presented results have a direct implication to separation science.
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Affiliation(s)
- Xiaobing Chen
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Yaowen Cui
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Habtom B Gobeze
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Daniel G Kuroda
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
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27
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Ghorai PK, Matyushov DV. Equilibrium Solvation, Electron-Transfer Reactions, and Stokes-Shift Dynamics in Ionic Liquids. J Phys Chem B 2020; 124:3754-3769. [DOI: 10.1021/acs.jpcb.0c01773] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Pradip Kr. Ghorai
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, India
| | - Dmitry V. Matyushov
- Department of Physics and School of Molecular Sciences, Arizona State University, PO Box 871504, Tempe, Arizona 85287, United States
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28
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Tarif E, Mondal J, Biswas R. How frictional response during solute solvation controls solute rotation in naturally abundant deep eutectic solvent (NADES)? A case study with amino acid derivative containing DES. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.112451] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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29
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Spectroscopic Studies of a Phosphonium Ionic Liquid in Supercritical CO2. CHEMENGINEERING 2020. [DOI: 10.3390/chemengineering4020020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Fluorescence spectroscopy was used to study a solution comprised of coumarin 153 (C153)+ trihexyltetradecylphosphonium bis(trifluoromethylsulfonyl)imide ([P6,6,6,14]+ [Tf2N]−)+ supercritical CO2 (scCO2). We compare the spectroscopy of C153 in neat scCO2 to that of C153/scCO2 with the addition of ionic liquid (IL). Excitation and emission peak frequencies of C153 in scCO2 and in IL/scCO2 diverged at reduced densities (ρr = ρ/ρc) below the CO2 critical density. At low fluid density, spectral changes in the IL/scCO2 solutions showed evidence that C153 experiences a very different microenvironment—one that is unlike neat scCO2. The data show that the presence of IL clearly influences the C153 excitation and emission profiles. Excitation was broadened and red shifted by >2000 cm−1 and the presence of an additional low-energy emission component that was red shifted by ~3000 cm−1 was clearly visible and not observed in neat scCO2. The solution heterogeneity was controlled by changing the scCO2 density and at high fluid density, both the excitation and emission spectra were more similar to those in neat scCO2. Steady-state anisotropy also showed that at low fluid density, the C153 emission was significantly polarized. Aggregation of C153 has been reported in the literature and this led us to hypothesize the possibility that C153 dimer (aggregation) formation may be occurring in scCO2. Another possible explanation is that dye–IL aggregates may dissolve into the scCO2 phase due to C153 acting as a “co-solvent” for the IL. Time-resolved intensity decay measurements yielded only slightly non-exponential decays with accompanying time constants of ~3–4 ns that were significantly shorter than the 5–6 ns time constants in neat scCO2, which are suggestive of C153–IL interactions. However, these data did not conclusively support dimer formation. Pre-exponential factors of the time constants showed that almost all of the emission was due to monomeric C153.
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30
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Hossain SS, Paul S, Samanta A. Complete Solvation Dynamics of Coumarin 153 in Tetraalkylammonium Bromide-Based Deep Eutectic Solvents. J Phys Chem B 2020; 124:2473-2481. [DOI: 10.1021/acs.jpcb.0c00594] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Sk Saddam Hossain
- School of Chemistry, University of Hyderabad, Hyderabad 500 046, India
| | - Sneha Paul
- School of Chemistry, University of Hyderabad, Hyderabad 500 046, India
| | - Anunay Samanta
- School of Chemistry, University of Hyderabad, Hyderabad 500 046, India
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31
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Kimura Y. Solvation heterogeneity in ionic liquids as demonstrated by photo-chemical reactions. PURE APPL CHEM 2020. [DOI: 10.1515/pac-2019-1116] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
It has been recognised that ionic liquids (ILs) with long alkyl-chains have a segregated structure due to the inhomogeneous distribution of polar parts and non-polar parts. This inhomogeneity of ILs brings about unique solvation phenomena of solute molecules dissolved in ILs. We have investigated various solvation-state selective phenomena by using laser spectroscopic techniques such as solvation state selective vibrational spectroscopy, translational and rotational dynamics of small molecules in ILs, and solvation state selective fundamental chemical reactions. In this paper, we have reviewed an intramolecular electron transfer (ET) reaction in the Marcus inverted region of N,N-dimethyl-p-nitroaniline and an intramolecular proton transfer (IPT) reaction in 4′-N,N-diethylamino-3-hydroxyflavone as examples of chemical reactions affected by unique solvation in ILs.
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Affiliation(s)
- Yoshifumi Kimura
- Department of molecular science and biochemistry, Faculty of science and engineering , Doshisha University , Kyotanabe-city, Kyoto 610-0321 , Japan
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32
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Fedunov RG, Yermolenko IP, Nazarov AE, Ivanov AI, Rosspeintner A, Angulo G. Theory of fluorescence spectrum dynamics and its application to determining the relaxation characteristics of the solvent and intramolecular vibrations. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2019.112016] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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33
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Yalcin D, Drummond CJ, Greaves TL. Solvation properties of protic ionic liquids and molecular solvents. Phys Chem Chem Phys 2020; 22:114-128. [DOI: 10.1039/c9cp05711k] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ionic liquids (ILs) are highly tailorable solvents with many potential applications. Knowledge about their solvation properties is highly beneficial in the utilization of ILs for specific tasks, though for many ILs this is currently unknown.
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Affiliation(s)
- Dilek Yalcin
- School of Science
- College of Science
- Engineering and Health
- RMIT University
- Melbourne
| | - Calum J. Drummond
- School of Science
- College of Science
- Engineering and Health
- RMIT University
- Melbourne
| | - Tamar L. Greaves
- School of Science
- College of Science
- Engineering and Health
- RMIT University
- Melbourne
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34
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Tarif E, Mondal J, Biswas R. Interaction and Dynamics in a Fully Biodegradable Glucose-Containing Naturally Abundant Deep Eutectic Solvent: Temperature-Dependent Time-Resolved Fluorescence Measurements. J Phys Chem B 2019; 123:9378-9387. [PMID: 31599593 DOI: 10.1021/acs.jpcb.9b06783] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A new room-temperature deep eutectic solvent (DES) composed of glucose, urea, and water has been prepared and its relaxation dynamics explored via temperature-dependent time-resolved fluorescence measurements employing hydrophilic and hydrophobic solute probes. Differential scanning calorimetry measurements indicate a glass transition temperature (Tg) of ∼236 K. Measured viscosity coefficients (η) vary from ∼600 to ∼100 cP in the temperature range 318 ≤ T/K ≤ 343 and exhibit Arrhenius-type temperature dependence with an activation energy of ∼65 kJ mol-1. Interestingly, this DES forms a stable liquid at ∼300 K but is too viscous to be accurately measured by us below 318 K. Temperature-dependent dynamic fluorescence anisotropy measurements using hydrophobic and hydrophilic solutes of similar sizes reveal bi-exponential kinetics and Arrhenius-type temperature dependence for solute rotation times (⟨τr⟩) but with significantly decreased activation energies, ∼31 kJ mol-1 (hydrophobic) and ∼21 kJ mol-1 (hydrophilic). Deviation from hydrodynamics is further reflected in the strong fractional viscosity dependence of ⟨τr⟩: ⟨τr⟩ ∝ (η/T)p with p ≈ 0.3-0.5, indicating pronounced temporal heterogeneity in the relaxation dynamics. Dynamic fluorescence Stokes shift measurements (temporal resolution ∼85 ps) produce dynamic shifts of ∼500-700 cm-1, bi-exponential solvation energy relaxation with time constants in the range ∼0.2 ns and ∼4 ns, and estimated missing amplitudes of ∼65-75%. Impact of the density difference between a nonpolar solvent and this DES on the estimated missing amplitudes is explored via measuring the temperature-dependent densities and refractive indices of this DES. Lifetime measurements suggest considerable temperature dependence for the hydrophobic solute but no such dependence for the hydrophilic one. Excitation energy dependence of fluorescence emission of various solutes with widely different lifetimes indicates mild spatial heterogeneity for this DES.
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Affiliation(s)
- Ejaj Tarif
- Chemical, Biological and Macromolecular Sciences (CBMS) , S. N. Bose National Centre for Basic Sciences , JD Block, Sector III, Salt Lake , Kolkata 700106 , India
| | - Jayanta Mondal
- Chemical, Biological and Macromolecular Sciences (CBMS) , S. N. Bose National Centre for Basic Sciences , JD Block, Sector III, Salt Lake , Kolkata 700106 , India
| | - Ranjit Biswas
- Chemical, Biological and Macromolecular Sciences (CBMS) , S. N. Bose National Centre for Basic Sciences , JD Block, Sector III, Salt Lake , Kolkata 700106 , India
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35
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Solvent dependent relaxation dynamics in lithium ion battery electrolytes: Coupling to medium friction. J Mol Liq 2019. [DOI: 10.1016/j.molliq.2019.111225] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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36
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An Experimental and Theoretical Test of Dielectric Friction Models Using Rotational Diffusion of 7-Diethylamino-2-H-1-Benzopyran-2-One in Non-associative Solvents. J Fluoresc 2019; 29:899-909. [PMID: 31273534 DOI: 10.1007/s10895-019-02402-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Accepted: 06/10/2019] [Indexed: 10/26/2022]
Abstract
The rotational re-orientations times of the 7-DHB dye molecule have been examined in non-associative solvents (DMSO and Octanenitrile) by varying the temperature, by employing the Steady-State Fluorescence Depolarisation and Time-Correlated Single Photon Counting (TCSPC) techniques. Rotational re-orientations time values in DMSO are found larger by a factor of 1.136 than octanenitrile, which indicates that 7-DHB laser dye is experiencing higher friction in DMSO than octanenitrile. To determine mechanical friction Stokes Einstein's Debye theory (SED) -with a stick, slip boundary conditions parameters are used and found an interesting super slip trend. Point dipole models as Nee-Zwanzig (NZ) and van der Zwan-Hynes (ZH) fail to explain experimental dielectric friction observed trends. Alavi-Waldeck model successfully explains the observed dielectric friction trend in non-associative solvents.
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37
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Kumar A, Nadaf Y, Renuka C, Ananthamurthy S. Investigations of mechanical and dielectric friction: Rotational reorientation studies of 7-DHB, Qu-390, and C-6H molecules in polar solvents. J Mol Liq 2019. [DOI: 10.1016/j.molliq.2019.04.120] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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38
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Kumar A, Renuka C, Nadaf Y. Fluorescence relaxation dynamics in excited electronic states of -(1,3-benzothiazol-2-yl)-7-(diethylamino) chromen-2-one (3-BDC) in alcohols. J Mol Struct 2019. [DOI: 10.1016/j.molstruc.2019.03.069] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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39
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Smortsova Y, Miannay FA, Koverga V, Dubois J, Kalugin O, Idrissi A. Fluorescent probe dependence of the solvation dynamics in ionic liquid BmimBF4 and propylene carbonate mixtures: a time-resolved fluorescence and quantum chemistry study. J Mol Liq 2019. [DOI: 10.1016/j.molliq.2019.02.123] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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40
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Wang X, Zhang S, Yao J, Li H. The Polarity of Ionic Liquids: Relationship between Relative Permittivity and Spectroscopic Parameters of Probe. Ind Eng Chem Res 2019. [DOI: 10.1021/acs.iecr.9b00485] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Xinyu Wang
- Department of Chemistry, ZJU-NHU United R&D Center, Zhejiang University, Hangzhou 310027, P.R. China
| | - Songna Zhang
- Department of Chemistry, ZJU-NHU United R&D Center, Zhejiang University, Hangzhou 310027, P.R. China
| | - Jia Yao
- Department of Chemistry, ZJU-NHU United R&D Center, Zhejiang University, Hangzhou 310027, P.R. China
| | - Haoran Li
- Department of Chemistry, ZJU-NHU United R&D Center, Zhejiang University, Hangzhou 310027, P.R. China
- State Key Laboratory of Chemical Engineering, Department of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, P.R. China
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41
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Kumar A, Nadaf YF, Renuka CG. Rotational Diffusion of Medium Sized 7-[Diethylamino]-2H-1-Benzopyran-2-One Molecule in Alcohols: Study of Temperature and Solvent Viscosity Effect. J Fluoresc 2019; 29:587-597. [PMID: 30949877 DOI: 10.1007/s10895-019-02370-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 03/19/2019] [Indexed: 11/30/2022]
Abstract
The rotational re-orientations times of the 7-[diethylamino]-2H-1-benzopyran-2-one (7-DHB) dye molecule have been examined in ethanol and octanol solvents when macroscopic solvent viscosity parameter is varied by varying the temperature, by employing the steady-state fluorescence depolarisation and Time-Correlated Single Photon Counting (TCSPC) techniques. Experimental observation shows that 7-DHB probe is experiencing higher friction in octanol compared to ethanol and rotates slower by a factor of 7.3. The hydrodynamic Stokes Einstein's Debye theory (SED) with a stick, slip boundary conditions parameters, quasi-hydrodynamic models (Dote-Kivelson-Schwartz and Geirer-Wirtz) were used to determine mechanical friction and found an interesting towards super slip trend. Dielectric frictional theories of point dipole, Nee-Zwanzig and van der Zwan-Hynes both models fail to describe experimentally observe dielectric friction trends. Evidently, both hydrodynamic and dielectric models failed to explain the examined behavior, even in the qualitative way in alcohols.
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Affiliation(s)
- Anil Kumar
- P.G. Department of Physics, Sri Siddeshwara Govt., First Grade College, Naragund, 582207, India
| | - Y F Nadaf
- Department of Physics and Research Center, Maharani Science College for Women, Bengaluru, 560001, India
| | - C G Renuka
- Department of Physics, Jnanabharathi campus, Bangalore University, Bengaluru, 560056, India.
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42
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Heid E, Schröder C. Polarizability in ionic liquid simulations causes hidden breakdown of linear response theory. Phys Chem Chem Phys 2019; 21:1023-1028. [PMID: 30601488 DOI: 10.1039/c8cp06569a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The validity of linear response theory (LRT) in computer simulations of solvation dynamics, i.e. the time-dependent Stokes shift, has been debated widely during the last decades. Since the use of LRT is computationally less expensive than the calculation of the true nonequilibrium response, it is often invoked for large systems exhibiting a particularly slow solvation response, e.g. ionic liquids. In the case of ionic liquids, LRT does not only need to capture the correct overall dynamics of the system, but also the contributions and timescales of the respective cation and anion movement. We show by large scale computer simulations that the contribution of the permanent dipoles to the solvation response obeys LRT to some extent, whereas the induced contributions in polarizable simulations lead to a failure of LRT for the respective ion contributions.
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Affiliation(s)
- Esther Heid
- University of Vienna, Faculty of Chemistry, Department of Computational Biological Chemistry, Währingerstraße 19, A-1090 Vienna, Austria.
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Dutta R, Jana G, Mondal D, Pyne A, Sil S, Chattaraj PK, Sarkar N. The role of viscosity in various dynamical processes of different fluorophores in ionic liquid–cosolvent mixtures: a femtosecond fluorescence upconversion study. Photochem Photobiol Sci 2019; 18:1359-1372. [DOI: 10.1039/c9pp00045c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Literature reports provide ample evidence of the dynamical studies of various fluorophores in different room-temperature ionic liquid (RTIL)–cosolvent mixtures.
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Affiliation(s)
- Rupam Dutta
- Department of Chemistry
- Indian Institute of Technology Kharagpur
- Kharagpur
- India
| | - Gourhari Jana
- Department of Chemistry and Center for Theoretical Studies
- Indian Institute of Technology Kharagpur
- Kharagpur
- India
| | - Dipankar Mondal
- Department of Chemistry
- Indian Institute of Technology Kharagpur
- Kharagpur
- India
| | - Arghajit Pyne
- Department of Chemistry
- Indian Institute of Technology Kharagpur
- Kharagpur
- India
| | - Sourav Sil
- Department of Chemistry
- Indian Institute of Technology Kharagpur
- Kharagpur
- India
| | - Pratim K. Chattaraj
- Department of Chemistry and Center for Theoretical Studies
- Indian Institute of Technology Kharagpur
- Kharagpur
- India
| | - Nilmoni Sarkar
- Department of Chemistry
- Indian Institute of Technology Kharagpur
- Kharagpur
- India
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Turner AH, Kim D. Rotation and translation dynamics of coumarin 153 in choline chloride-based deep eutectic solvents. J Chem Phys 2018; 149:174503. [DOI: 10.1063/1.5038067] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Adam H. Turner
- Department of Physics, Sogang University, Seoul, South Korea
| | - Doseok Kim
- Department of Physics, Sogang University, Seoul, South Korea
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Brinzer T, Daly CA, Allison C, Garrett-Roe S, Corcelli SA. Modeling Carbon Dioxide Vibrational Frequencies in Ionic Liquids: III. Dynamics and Spectroscopy. J Phys Chem B 2018; 122:8931-8942. [PMID: 30160958 DOI: 10.1021/acs.jpcb.8b05659] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In recent years, interest in carbon capture and sequestration has led to numerous investigations of the ability of ionic liquids to act as recyclable CO2-sorbent materials. Herein, we investigate the structure and dynamics of a model physisorbing ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate ([C4C1Im][PF6]), from the perspective of CO2 using two-dimensional (2D) IR spectroscopy and molecular dynamics simulations. A direct comparison of experimentally measured and calculated 2D IR line shapes confirms the validity of the simulations and spectroscopic calculations. Taken together, the simulations and experiments reveal new insights into the interactions of a CO2 solute with the surrounding ionic liquid and how these interactions manifest in the 2D IR spectra. In particular, higher CO2 asymmetric stretch vibrational frequencies are associated with softer, less populated solvent cages and lower frequencies are associated with tighter, more highly populated solvent cages. The CO2 interacts most strongly with the anions, and these interactions persist for more than 1 ns. The second strongest interactions are with the imidazolium cation ring that last 100 ps, and the weakest interactions are with the cation butyl tail that persist for 10 ps. The principal contributors to spectral diffusion of the CO2 asymmetric stretch vibrational frequency due to the dynamical evolution of the solvent are through Lennard-Jones interactions at short times and electrostatics at long times.
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Affiliation(s)
- Thomas Brinzer
- Department of Chemistry , University of Pittsburgh , 219 Parkman Avenue , Pittsburgh , Pennsylvania 15260 , United States.,Pittsburgh Quantum Institute , University of Pittsburgh , 3943 O'Hara Street , Pittsburgh , Pennsylvania 15260 , United States
| | - Clyde A Daly
- Department of Chemistry and Biochemistry , University of Notre Dame , 251 Nieuwland Science Hall , Notre Dame , Indiana 46656 , United States
| | - Cecelia Allison
- Department of Chemistry and Biochemistry , University of Notre Dame , 251 Nieuwland Science Hall , Notre Dame , Indiana 46656 , United States
| | - Sean Garrett-Roe
- Department of Chemistry , University of Pittsburgh , 219 Parkman Avenue , Pittsburgh , Pennsylvania 15260 , United States.,Pittsburgh Quantum Institute , University of Pittsburgh , 3943 O'Hara Street , Pittsburgh , Pennsylvania 15260 , United States
| | - Steven A Corcelli
- Department of Chemistry and Biochemistry , University of Notre Dame , 251 Nieuwland Science Hall , Notre Dame , Indiana 46656 , United States
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Terranova ZL, Corcelli SA. Decompositions of Solvent Response Functions in Ionic Liquids: A Direct Comparison of Equilibrium and Nonequilibrium Methodologies. J Phys Chem B 2018; 122:6823-6828. [DOI: 10.1021/acs.jpcb.8b04235] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Z. L. Terranova
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - S. A. Corcelli
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
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Rumble CA, Maroncelli M. Solvent controlled intramolecular electron transfer in mixtures of 1-butyl-3-methylimidizolium tetrafluoroborate and acetonitrile. J Chem Phys 2018; 148:193801. [DOI: 10.1063/1.5000727] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Christopher A. Rumble
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Mark Maroncelli
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
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Wu B, Liang M, Zmich N, Hatcher J, Lall-Ramnarine SI, Wishart JF, Maroncelli M, Castner EW. Photoinduced Bimolecular Electron Transfer in Ionic Liquids: Cationic Electron Donors. J Phys Chem B 2018; 122:2379-2388. [PMID: 29377698 DOI: 10.1021/acs.jpcb.7b12542] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Recently, we have reported a systematic study of photoinduced electron-transfer reactions in ionic liquid solvents using neutral and anionic electron donors and a series of cyano-substituted anthracene acceptors [ Wu , B. ; Maroncelli , M. ; Castner , E. W. Jr Photoinduced Bimolecular Electron Transfer in Ionic Liquids . J. Am. Chem. Soc. 139 , 2017 , 14568 ]. Herein, we report complementary results for a cationic class of 1-alkyl-4-dimethylaminopyridinium electron donors. Reductive quenching of cyano-substituted anthracene fluorophores by these cationic quenchers is studied in solutions of acetonitrile and the ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide. Varying the length of the alkyl chain permits tuning of the quencher diffusivities in solution. The observed quenching kinetics are interpreted using a diffusion-reaction analysis. Together with results from the prior study, these results show that the intrinsic electron-transfer rate constant does not depend on the quencher charge in this family of reactions.
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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
| | - Min Liang
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey , 610 Taylor Road, Piscataway, New Jersey 08854, United States
| | - Nicole Zmich
- Chemistry Division, Brookhaven National Laboratory , Upton, New York 11973, United States
| | - Jasmine Hatcher
- The Graduate Center of CUNY , 365 Fifth Avenue, New York, New York 10016, United States.,Hunter College, CUNY , 695 Park Avenue, New York, New York 10065, United States
| | - Sharon I Lall-Ramnarine
- Department of Chemistry, Queensborough Community College, City University of New York , Bayside, New York 11364, United States
| | - James F Wishart
- Chemistry Division, Brookhaven National Laboratory , Upton, New York 11973, 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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Heid E, Schröder C. Solvation dynamics in polar solvents and imidazolium ionic liquids: failure of linear response approximations. Phys Chem Chem Phys 2018; 20:5246-5255. [PMID: 29400383 PMCID: PMC5815284 DOI: 10.1039/c7cp07052g] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 01/19/2018] [Indexed: 12/18/2022]
Abstract
This study presents the large scale computer simulations of two common fluorophores, N-methyl-6-oxyquinolinium betaine and coumarin 153, in five polar or ionic solvents. The validity of linear response approximations to calculate the time-dependent Stokes shift is evaluated in each system. In most studied systems linear response theory fails. In ionic liquids the magnitude of the overall response is largely overestimated, and linear response theory is not able to capture the individual contributions of cations and anions. In polar liquids, the timescales of solvation dynamics are often not correctly reproduced. These observations are complemented by a detailed analysis of Gaussian statistics including higher order correlation functions, variance of the energy gap distribution and its time evolution. The analysis of higher order correlation functions was found to be not suitable to predict a failure of linear response theory. Further analysis of radial distribution functions and hydrogen bonds in the ground and excited state, as well as the time evolution of the number of hydrogen bonds after solute excitation reveal an influence of solvent structure in some of the studied systems.
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Affiliation(s)
- Esther Heid
- University of Vienna , Faculty of Chemistry , Department of Computational Biological Chemistry , Währingerstraße 19 , A-1090 Vienna , Austria . ; Tel: +43 14277 52711
| | - Christian Schröder
- University of Vienna , Faculty of Chemistry , Department of Computational Biological Chemistry , Währingerstraße 19 , A-1090 Vienna , Austria . ; Tel: +43 14277 52711
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Murakami Y, Das SK, Himuro Y, Maeda S. Triplet-sensitized photon upconversion in deep eutectic solvents. Phys Chem Chem Phys 2018; 19:30603-30615. [PMID: 29115349 DOI: 10.1039/c7cp06494b] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Photon upconversion (UC) is a technology that can increase solar utilization efficiencies in broad photoenergy conversion systems by converting lower-energy photons into usable higher-energy photons. Recently, UC using triplet-triplet annihilation (TTA) of organic molecules has drawn attention because it is presently the only method applicable to weak and noncoherent light. To date, many attempts have been made to realize this UC technology in forms suitable for applications, but they typically suffer from either high cost or insufficient stability and/or safety of materials. Recently, a new class of liquid called deep eutectic solvents (DESs) has emerged as low-cost green fluids that possess low toxicity and vapor pressure, biodegradability, and high thermal stability. DESs have been proposed as an alternative to ionic liquids. This article develops triplet-sensitized UC samples using DESs that are found to be suitable solvents for this purpose, attaining a new materials platform for UC with the aforementioned advantages. The high thermal stability of the samples is qualitatively confirmed and their UC quantum yields are determined to be 0.11-0.21 (based on the definition that the maximum quantum yield is 0.5) depending on the DES composition. The triplet lifetime of the emitter 9,10-diphenylanthracene increases with DES viscosity, resulting in unique kinetics. Analysis of photophysical experimental results allows the relevant physics governing the performance of this sample system to be determined and discussed. Overall, a novel UC platform that simultaneously achieves high thermal stability, low cost, and environmental friendliness is developed using DESs as the solvent.
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Affiliation(s)
- Yoichi Murakami
- School of Engineering, Tokyo Institute of Technology, 2-12-1-I1-15 Ookayama, Meguro-ku, Tokyo 152-8552, Japan.
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