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Eliasen KL, Gabriel J, Blochowicz T, Gainaru CP, Christensen TE, Niss K. What is the origin of slow relaxation modes in highly viscous ionic liquids? J Chem Phys 2024; 161:034506. [PMID: 39012811 DOI: 10.1063/5.0215661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2024] [Accepted: 06/27/2024] [Indexed: 07/18/2024] Open
Abstract
Room temperature ionic liquids (RTILs) are molten salts consisting entirely of ions and have over the past decades gained increased interest due to their high potential in applications. These structurally complex systems often display multiple relaxation modes in the response functions at lower frequencies, hinting to complex underlying mechanisms. While the existence of these multimodal spectra in the shear mechanical, dielectric, and light scattering response of RTILs has been confirmed multiple times, controversy still surrounds the origin. This paper, therefore, aims to provide additional insights into the multimodal spectra seen in RTILs by presenting new shear mechanical results on seven different RTILs: Pyr1n-TFSI with n = 4, 6, and 8; Pyr18-TFSI mixed with Li-TFSI in two high concentrations; and Cn-mim-BF4 with n = 3 and 8. Dynamic depolarized light scattering was also measured on one of the Pyr18-TFSI Li-salt mixtures. These specific cases were analyzed in detail and put into a bigger perspective together with an overview of the literature. Recent literature offers two specific explanations for the origin of the multimodal shear mechanical spectra: (1) cation-anion time scale separation or (2) combined cation-anion relaxation in addition to a dynamic signal from mesoscale aggregates at lower frequencies. However, neither of these two pictures can consistently explain all the results on different ionic liquids. Instead, we conclude that the origin of the multimodal spectrum is system specific. This underlines the complexity of this class of liquids and shows that great care must be taken when making general conclusions based on specific cases.
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Affiliation(s)
- Kira L Eliasen
- "Glass and Time," IMFUFA, Department of Science and Environment, Roskilde University, Roskilde 4000, Denmark
| | - Jan Gabriel
- "Glass and Time," IMFUFA, Department of Science and Environment, Roskilde University, Roskilde 4000, Denmark
| | - Thomas Blochowicz
- Institut für Festkörperphysik, Technische Universität Darmstadt, Darmstadt 64289, Germany
| | - Catalin P Gainaru
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Tage E Christensen
- "Glass and Time," IMFUFA, Department of Science and Environment, Roskilde University, Roskilde 4000, Denmark
| | - Kristine Niss
- "Glass and Time," IMFUFA, Department of Science and Environment, Roskilde University, Roskilde 4000, Denmark
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2
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Emerson M, Ivanov AS, Gallington LC, Maltsev DS, Halstenberg P, Dai S, Roy S, Bryantsev VS, Margulis CJ. Heterogeneous Structure, Mechanisms of Counterion Exchange, and the Spacer Salt Effect in Complex Molten Salt Mixtures Including LaCl 3. J Phys Chem B 2024; 128:3972-3980. [PMID: 38624173 PMCID: PMC11056984 DOI: 10.1021/acs.jpcb.4c01429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2024] [Revised: 03/22/2024] [Accepted: 03/26/2024] [Indexed: 04/17/2024]
Abstract
Complex molten chloride salt mixtures of uranium, magnesium, and sodium are top candidates for promising nuclear energy technologies to produce electricity based on molten salt reactors. From a local structural perspective, LaCl3 is similar to UCl3 and hence a good proxy to study these complex salt mixtures. As fission products, lanthanide salts and their mixtures are also very important in their own right. This article describes from an experimental and theory perspective how very different the structural roles of MgCl2 and NaCl are in mixtures with LaCl3. We find that, whereas MgCl2 becomes an integral part of multivalent ionic networks, NaCl separates them. In a recent article (J. Am. Chem. Soc. 2022, 144, 21751-21762) we have called the disruptive behavior of NaCl "the spacer salt effect". Because of the heterogeneous nature of these salt mixtures, there are multiple structural motifs in the melt, each with its particular free energetics. Our work identifies and quantifies these; it also elucidates the mechanisms through which Cl- ions exchange between Mg2+-rich and La3+-rich environments.
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Affiliation(s)
- Matthew
S. Emerson
- Department
of Chemistry, The University of Iowa, Iowa City, Iowa 52242, United States
| | - Alexander S. Ivanov
- Chemical
Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | | | - Dmitry S. Maltsev
- Chemical
Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Phillip Halstenberg
- Chemical
Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Department
of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Sheng Dai
- Chemical
Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Department
of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Santanu Roy
- Chemical
Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Vyacheslav S. Bryantsev
- Chemical
Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Claudio J. Margulis
- Department
of Chemistry, The University of Iowa, Iowa City, Iowa 52242, United States
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3
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Wang J, Li H, Warr GG, Chen F, Atkin R. Nanostructure and Dynamics of Aprotic Ionic Liquids at Graphite Electrodes as a Function of Potential. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024:e2311353. [PMID: 38573945 DOI: 10.1002/smll.202311353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 03/05/2024] [Indexed: 04/06/2024]
Abstract
Atomic force microscope (AFM) videos reveal the near-surface nanostructure and dynamics of the ionic liquids (ILs) 1-butyl-3-methylimidazolium dicyanamide (BMIM DCA) and 1-hexyl-3-methylimidazolium dicyanamide (HMIM DCA) above highly oriented pyrolytic graphite (HOPG) electrodes as a function of surface potential. Molecular dynamics (MD) simulations reveal the molecular-level composition of the nanostructures. In combination, AFM and MD show that the near-surface aggregates form via solvophobic association of the cation alkyl chains at the electrode interface. The diffusion coefficients of interfacial nanostructures are ≈0.01 nm2 s-1 and vary with the cation alkyl chain length and the surface potential. For each IL, the nanostructure diffusion coefficients are similar at open-circuit potential (OCP) and OCP + 1V, but BMIM DCA moves about twice as fast as HMIM DCA. At negative potentials, the diffusion coefficient decreases for BMIM DCA and increases for HMIM DCA. When the surface potential is switched from negative to positive, a sudden change in the direction of the nanostructure motion is observed for both BMIM DCA and HMIM DCA. No transient dynamics are noted following other potential jumps. This study provides a new fundamental understanding regarding the dynamics of electrochemically stable ILs at electrodes vital for the rational development of IL-based electrochemical devices.
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Affiliation(s)
- Jianan Wang
- School of Molecular Sciences, The University of Western Australia, 35 Stirling Hwy, Perth, WA, 6009, Australia
| | - Hua Li
- School of Molecular Sciences, The University of Western Australia, 35 Stirling Hwy, Perth, WA, 6009, Australia
- Centre for Microscopy, Characterisation and Analysis, The University of Western Australia, 35 Stirling Hwy, Perth, WA, 6009, Australia
| | - Gregory G Warr
- School of Chemistry and Sydney Nano Institute, The University of Sydney, Sydney, NSW, 2006, Australia
| | - Fangfang Chen
- Institute for Frontier Materials (IFM), Deakin University, Waurn Ponds, Geelong, VIC, 3216, Australia
| | - Rob Atkin
- School of Molecular Sciences, The University of Western Australia, 35 Stirling Hwy, Perth, WA, 6009, Australia
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4
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Wang X, Nayak S, Wilson RE, Soderholm L, Servis MJ. Solvent effects on extractant conformational energetics in liquid-liquid extraction: a simulation study of molecular solvents and ionic liquids. Phys Chem Chem Phys 2024; 26:2877-2886. [PMID: 38048065 DOI: 10.1039/d3cp04680j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
Extractant design in liquid-liquid extraction (LLE) is a research frontier of metal ion separations that typically focuses on the direct extractant-metal interactions. However, a more detailed understanding of energetic drivers of separations beyond primary metal coordination is often lacking, including the role of solvent in the extractant phase. In this work, we propose a new mechanism for enhancing metal-complexant energetics with nanostructured solvents. Using molecular dynamics simulations with umbrella sampling, we find that the organic solvent can reshape the energetics of the extractant's intramolecular conformational landscape. We calculate free energy profiles of different conformations of a representative bidentate extractant, n-octyl(phenyl)-N,N-diisobutyl carbamoyl methyl phosphinoxide (CMPO), in four different solvents: dodecane, tributyl phosphate (TBP), and dry and wet ionic liquid (IL) 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM][Tf2N]). By promoting reorganization of the extractant molecule into its binding conformation, our findings reveal how particular solvents can ameliorate this unfavorable step of the metal separation process. In particular, the charge alternating nanodomains formed in ILs substantially reduce the free energy penalty associated with extractant reorganization. Importantly, using alchemical free energy calculations, we find that this stabilization persists even when we explicitly include the extracted cation. These findings provide insight into the energetic drivers of metal ion separations and potentially suggest a new approach to designing effective separations using a molecular-level understanding of solvent effects.
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Affiliation(s)
- Xiaoyu Wang
- Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 S Cass Ave, Lemont, IL 60439, USA.
| | - Srikanth Nayak
- Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 S Cass Ave, Lemont, IL 60439, USA.
| | - Richard E Wilson
- Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 S Cass Ave, Lemont, IL 60439, USA.
| | - L Soderholm
- Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 S Cass Ave, Lemont, IL 60439, USA.
| | - Michael J Servis
- Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 S Cass Ave, Lemont, IL 60439, USA.
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5
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Hammond OS, Bousrez G, Mehler F, Li S, Shimpi MR, Doutch J, Cavalcanti L, Glavatskih S, Antzutkin ON, Rutland MW, Mudring AV. Molecular Architecture Effects on Bulk Nanostructure in Bis(Orthoborate) Ionic Liquids. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2300912. [PMID: 37395635 DOI: 10.1002/smll.202300912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 04/11/2023] [Indexed: 07/04/2023]
Abstract
A series of 19 ionic liquids (ILs) based on phosphonium and imidazolium cations of varying alkyl-chain lengths with the orthoborate anions bis(oxalato)borate [BOB]- , bis(mandelato)borate, [BMB]- and bis(salicylato)borate, [BScB]- , are synthesized and studied using small-angle neutron scattering (SANS). All measured systems display nanostructuring, with 1-methyl-3-n-alkyl imidazolium-orthoborates forming clearly bicontinuous L3 spongelike phases when the alkyl chains are longer than C6 (hexyl). L3 phases are fitted using the Teubner and Strey model, and diffusely-nanostructured systems are primarily fitted using the Ornstein-Zernicke correlation length model. Strongly-nanostructured systems have a strong dependence on the cation, with molecular architecture variation explored to determine the driving forces for self-assembly. The ability to form well-defined complex phases is effectively extinguished in several ways: methylation of the most acidic imidazolium ring proton, replacing the imidazolium 3-methyl group with a longer hydrocarbon chain, substitution of [BOB]- by [BMB]- , or exchanging the imidazolium for phosphonium systems, irrespective of phosphonium architecture. The results suggest there is only a small window of opportunity, in terms of molecular amphiphilicity and cation:anion volume matching, for the formation of stable extensive bicontinuous domains in pure bulk orthoborate-based ILs. Particularly important for self-assembly processes appear to be the ability to form H-bonding networks, which offer additional versatility in imidazolium systems.
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Affiliation(s)
- Oliver S Hammond
- Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, SE-114 18, Sweden
- Department of Biological and Chemical Engineering and iNANO, Aarhus University, Aarhus C, 8000, Denmark
| | - Guillaume Bousrez
- Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, SE-114 18, Sweden
- Department of Biological and Chemical Engineering and iNANO, Aarhus University, Aarhus C, 8000, Denmark
| | - Filip Mehler
- Division of Surface and Corrosion Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, SE-100 40, Sweden
| | - Sichao Li
- Division of Surface and Corrosion Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, SE-100 40, Sweden
| | - Manishkumar R Shimpi
- Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, SE-114 18, Sweden
- Chemistry of Interfaces, Luleå University of Technology, Luleå, SE-971 87, Sweden
| | - James Doutch
- ISIS Neutron & Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell-Oxford, OX11 0QX, UK
| | - Leide Cavalcanti
- ISIS Neutron & Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell-Oxford, OX11 0QX, UK
| | - Sergei Glavatskih
- Department of Engineering Design, KTH Royal Institute of Technology, Stockholm, SE-10044, Sweden
- School of Chemistry, University of New South Wales, Sydney, 2052, Australia
- Department of Electromechanical, Systems and Metal Engineering, Ghent University, Ghent, B-9052, Belgium
| | - Oleg N Antzutkin
- Chemistry of Interfaces, Luleå University of Technology, Luleå, SE-971 87, Sweden
| | - Mark W Rutland
- Division of Surface and Corrosion Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, SE-100 40, Sweden
- School of Chemistry, University of New South Wales, Sydney, 2052, Australia
- Bioeconomy and Health Department Materials and Surface Design, RISE Research Institutes of Sweden, Stockholm, SE-114 86, Sweden
- Laboratoire de Tribologie et Dynamique des Systèmes, École Centrale de Lyon, Lyon, 69130, France
| | - Anja-Verena Mudring
- Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, SE-114 18, Sweden
- Department of Biological and Chemical Engineering and iNANO, Aarhus University, Aarhus C, 8000, Denmark
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6
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Yao B, Paluch M, Paturej J, McLaughlin S, McGrogan A, Swadzba-Kwasny M, Shen J, Ruta B, Rosenthal M, Liu J, Kruk D, Wojnarowska Z. Self-Assembled Nanostructures in Aprotic Ionic Liquids Facilitate Charge Transport at Elevated Pressure. ACS APPLIED MATERIALS & INTERFACES 2023; 15:39417-39425. [PMID: 37555825 PMCID: PMC10450691 DOI: 10.1021/acsami.3c08606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Accepted: 08/01/2023] [Indexed: 08/10/2023]
Abstract
Ionic liquids (ILs), revealing a tendency to form self-assembled nanostructures, have emerged as promising materials in various applications, especially in energy storage and conversion. Despite multiple reports discussing the effect of structural factors and external thermodynamic variables on ion organization in a liquid state, little is known about the charge-transport mechanism through the self-assembled nanostructures and how it changes at elevated pressure. To address these issues, we chose three amphiphilic ionic liquids containing the same tetra(alkyl)phosphonium cation and anions differing in size and shape, i.e., thiocyanate [SCN]-, dicyanamide [DCA]-, and tricyanomethanide [TCM]-. From ambient pressure dielectric and mechanical experiments, we found that charge transport of all three examined ILs is viscosity-controlled at high temperatures. On the other hand, ion diffusion is much faster than structural dynamics in a nanostructured supercooled liquid (at T < 210 ± 3 K), which constitutes the first example of conductivity independent from viscosity in neat aprotic ILs. High-pressure measurements and MD simulations reveal that the created nanostructures depend on the anion size and can be modified by compression. For small anions, increasing pressure shapes immobile alkyl chains into lamellar-type phases, leading to increased anisotropic diffusivity of anions through channels. Bulky anions drive the formation of interconnected phases with continuous 3D curvature, which render ion transport independent of pressure. This work offers insight into the design of high-density electrolytes with percolating conductive phases providing efficient ion flow.
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Affiliation(s)
- Beibei Yao
- Faculty
of Science and Technology, Institute of Physics, University of Silesia in Katowice, 75 Pułku Piechoty 1A, 41-500 Chorzów, Poland
| | - Marian Paluch
- Faculty
of Science and Technology, Institute of Physics, University of Silesia in Katowice, 75 Pułku Piechoty 1A, 41-500 Chorzów, Poland
| | - Jaroslaw Paturej
- Faculty
of Science and Technology, Institute of Physics, University of Silesia in Katowice, 75 Pułku Piechoty 1A, 41-500 Chorzów, Poland
| | - Shannon McLaughlin
- The
QUILL Research Centre, School of Chemistry and Chemical Engineering, The Queen’s University of Belfast, David Keir Building, Stranmillis
Road, BT9 5AG Belfast, NI, U.K.
| | - Anne McGrogan
- The
QUILL Research Centre, School of Chemistry and Chemical Engineering, The Queen’s University of Belfast, David Keir Building, Stranmillis
Road, BT9 5AG Belfast, NI, U.K.
| | - Malgorzata Swadzba-Kwasny
- The
QUILL Research Centre, School of Chemistry and Chemical Engineering, The Queen’s University of Belfast, David Keir Building, Stranmillis
Road, BT9 5AG Belfast, NI, U.K.
| | - Jie Shen
- Institut
Neel, 38000 Grenoble, France
- ESRF—The
European Synchrotron, CS 40220, 38043 Grenoble, France
| | - Beatrice Ruta
- Institut
Neel, 38000 Grenoble, France
- ESRF—The
European Synchrotron, CS 40220, 38043 Grenoble, France
| | - Martin Rosenthal
- Department
of Chemistry, KU Leuven, Celestijnenlaan 200F, Box 2404, B-3001 Leuven, Belgium
- Dual
Belgian
Beamline (DUBBLE), European Synchrotron
Radiation Facility, 71 Avenue des Martyrs, CS 40220, 38043 Grenoble Cedex 9, France
| | - Jiliang Liu
- ESRF—The
European Synchrotron, CS 40220, 38043 Grenoble, France
| | - Danuta Kruk
- Faculty
of Mathematics and Computer Science, University
of Warmia and Mazury in Olsztyn, Sloneczna 54, Olsztyn PL-10710, Poland
| | - Zaneta Wojnarowska
- Faculty
of Science and Technology, Institute of Physics, University of Silesia in Katowice, 75 Pułku Piechoty 1A, 41-500 Chorzów, Poland
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7
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Dhattarwal HS, Kashyap HK. Microstructures of Choline Amino Acid based Biocompatible Ionic Liquids. CHEM REC 2023; 23:e202200295. [PMID: 36960931 DOI: 10.1002/tcr.202200295] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2022] [Revised: 02/26/2023] [Indexed: 03/25/2023]
Abstract
Bio-compatible ionic liquids (Bio-ILs) represent a class of solvents with peculiar properties and exhibit huge potential for their applications in different fields of chemistry. Ever since they were discovered, researchers have used bio-ILs in diverse fields such as biomass dissolution, CO2 sequestration, and biodegradation of pesticides. This review highlights the ongoing research studies focused on elucidating the microscopic structure of bio-ILs based on cholinium cation ([Ch]+ ) and amino acid ([AA]- ) anions using the state-of-the-arta b i n i t i o ${ab\hskip0.25eminitio}$ and classical molecular dynamics (MD) simulations. The microscopic structure associated with these green ILs guides their suitability for specific applications. ILs of this class differ in the side chain of the amino acid anions, and varying the side chain significantly affects the structure of these ILs and thus helps in tuning the efficiency of biomass dissolution. This review demonstrates the central role of the side chain on the morphology of choline amino acid ([Ch][AA]) bio-ILs. The seemingly matured field of bio-ILs and their employment in various applications still holds significant potential, and the insights on their microscopic structure would steer the field of target specific application of these green ILs.
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Affiliation(s)
- Harender S Dhattarwal
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, 110016, India
| | - Hemant K Kashyap
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, 110016, India
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8
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Maji D, Biswas R. Dielectric relaxation and dielectric decrement in ionic acetamide deep eutectic solvents: Spectral decomposition and comparison with experiments. J Chem Phys 2023; 158:2888209. [PMID: 37139998 DOI: 10.1063/5.0147378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 04/17/2023] [Indexed: 05/05/2023] Open
Abstract
Frequency-dependent dielectric relaxation in three deep eutectic solvents (DESs), (acetamide+LiClO4/NO3/Br), was investigated in the temperature range, 329 ≤ T/K ≤ 358, via molecular dynamics simulations. Subsequently, decomposition of the real and the imaginary components of the simulated dielectric spectra was carried out to separate the rotational (dipole-dipole), translational (ion-ion), and ro-translational (dipole-ion) contributions. The dipolar contribution, as expected, was found to dominate all the frequency-dependent dielectric spectra over the entire frequency regime, while the other two components together made tiny contributions only. The translational (ion-ion) and the cross ro-translational contributions appeared in the THz regime in contrast to the viscosity-dependent dipolar relaxations that dominated the MHz-GHz frequency window. Our simulations predicted, in agreement with experiments, anion-dependent decrement of the static dielectric constant (ɛs ∼ 20 to 30) for acetamide (ɛs ∼ 66) in these ionic DESs. Simulated dipole-correlations (Kirkwood g factor) indicated significant orientational frustrations. The frustrated orientational structure was found to be associated with the anion-dependent damage of the acetamide H-bond network. Single dipole reorientation time distributions suggested slowed down acetamide rotations but did not indicate presence of any "rotationally frozen" molecule. The dielectric decrement is, therefore, largely static in origin. This provides a new insight into the ion dependence of the dielectric behavior of these ionic DESs. A good agreement between the simulated and the experimental timescales was also noticed.
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Affiliation(s)
- Dhrubajyoti Maji
- Department of Chemical and Biological Sciences, S. N. Bose National Centre for Basic Sciences, Block-JD, Sector III, Salt Lake, Kolkata, West Bengal 700106, India
| | - Ranjit Biswas
- Department of Chemical and Biological Sciences, S. N. Bose National Centre for Basic Sciences, Block-JD, Sector III, Salt Lake, Kolkata, West Bengal 700106, India
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9
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Singh N, Jha MK, Dhattarwal HS, Kashyap HK. How NaFTA salt affects the structural landscape and transport properties of Pyrr 1,3FTA ionic liquid. J Chem Phys 2023; 158:104502. [PMID: 36922141 DOI: 10.1063/5.0133966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2023] Open
Abstract
Recently, it has been demonstrated that ionic liquids (ILs) with an asymmetric anion render a wider operational temperature range and can be used as a solvent in sodium ion batteries. In the present study, we examine the microscopic structure and dynamics of pure 1-methyl-1-propylpyrrolidinium fluorosulfonyl(trifluoromethylsulfonyl)amide (Pyrr1,3FTA) IL using atomistic molecular dynamics simulations. How the addition of the sodium salt (NaFTA) having the same anion changes the structural landscape and transport properties of the pure IL has also been explored. The simulated x-ray scattering structure functions reveal that the gradual addition of NaFTA salt (up to 1.2 molal) suppresses the charge alternating feature of the pure IL because of the replacement of the Pyrr+ cations with the Na+ ions. The Na+ ions are majorly found near the oxygen atoms of the anions, but the probability of finding the Na+ ions near these atoms slightly decreases with increasing salt concentration. As expected, the Na+ ions stay away from the Pyrr+ cations. However, the probability of finding the anions around anions increases with increasing salt concentration. The simulated self-diffusion coefficients of the ions in the pure IL reveal slightly faster diffusion of the Pyrr+ cations as compared to the FTA- anions. Interestingly, in the salt solution, despite having smaller size, the diffusion of the Na+ ions is found to be lesser than the Pyrr+ cations and the FTA- anions. The analysis of the ionic conductivity and transport numbers reveals that the fractional contribution of the FTA- anion to the overall conductivity remains nearly constant with increasing salt concentration, but the contribution of Pyrr+ cation decreases and Na+ ion increases.
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Affiliation(s)
- Navneet Singh
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Mrityunjay K Jha
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Harender S Dhattarwal
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Hemant K Kashyap
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
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10
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Koutsoukos S, Avila J, Brooks NJ, Costa Gomes M, Welton T. Physical properties and nanostructuring of long-chained homobaric imidazolium ionic liquids. Phys Chem Chem Phys 2023; 25:6316-6325. [PMID: 36779289 DOI: 10.1039/d2cp05783b] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
Understanding the structure-property relationship and nanoscopic behaviour of ionic liquids is of utmost importance for their potential applications. Focusing these studies on sets of homobaric ionic liquids could provide important insight into the effects of specific chemical groups on the overall interaction profile, bringing researchers one step closer to succesfully designing ionic liquids which are tailor-made for specific applications. This work focuses on ionic liquids with 12 total carbons on their side chains, studying both their bulk physical properties (such as densities and viscosities) and their nanostructuring. The results reveal that by keeping the total number of carbons constant, but arranging them differently around the imidazolium ring, either in a linear or in a branched-chain formation, can result in compounds with quite distinct properties. Some of those (such as diffusivity) appear to be more sensitive to symmetry variations, while others (such as density) are not significantly affected. X-ray scattering is used in order to get a clearer understanding of the nanostructuring of the studied compounds and to investigate to what extent the observed macroscopic properties are directly linked to the nanoscale ordering.
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Affiliation(s)
- Spyridon Koutsoukos
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, White City Campus, London W12 0BZ, UK.
| | - Jocasta Avila
- Laboratoire de Chimie de l'ENS Lyon, CNRS and Université de Lyon, 46 allée d'Italie, 69364 Lyon, France
| | - Nicholas J Brooks
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, White City Campus, London W12 0BZ, UK.
| | - Margarida Costa Gomes
- Laboratoire de Chimie de l'ENS Lyon, CNRS and Université de Lyon, 46 allée d'Italie, 69364 Lyon, France
| | - Tom Welton
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, White City Campus, London W12 0BZ, UK.
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11
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Emerson MS, Sharma S, Roy S, Bryantsev VS, Ivanov AS, Gakhar R, Woods ME, Gallington LC, Dai S, Maltsev DS, Margulis CJ. Complete Description of the LaCl 3–NaCl Melt Structure and the Concept of a Spacer Salt That Causes Structural Heterogeneity. J Am Chem Soc 2022; 144:21751-21762. [DOI: 10.1021/jacs.2c09987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Matthew S. Emerson
- Department of Chemistry, The University of Iowa, Iowa City, Iowa 52242, United States
| | - Shobha Sharma
- Department of Chemistry, The University of Iowa, Iowa City, Iowa 52242, United States
| | - Santanu Roy
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Vyacheslav S. Bryantsev
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Alexander S. Ivanov
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Ruchi Gakhar
- Pyrochemistry and Molten Salt Systems Department, Idaho National Laboratory, Idaho Falls, Idaho 83415, United States
| | - Michael E. Woods
- Pyrochemistry and Molten Salt Systems Department, Idaho National Laboratory, Idaho Falls, Idaho 83415, United States
| | - Leighanne C. Gallington
- X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, Lemont, Illinois 60439, United States
| | - Sheng Dai
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Dmitry S. Maltsev
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Claudio J. Margulis
- Department of Chemistry, The University of Iowa, Iowa City, Iowa 52242, United States
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12
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Triolo A, Paolone A, Sarra A, Trequattrini F, Palumbo O, BattistaAppetecchi G, Lo Celso F, Chater P, Russina O. Structure and vibrational features of the protic ionic liquid 1,8-diazabicyclo[5.4.0]-undec-7-ene-8-ium bis(trifluoromethanesulfonyl)amide, [DBUH][TFSI]. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2021.117981] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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13
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Mudring AV, Hammond O. Ionic Liquids and Deep Eutectics as a Transformative Platform for the Synthesis of Nanomaterials. Chem Commun (Camb) 2022; 58:3865-3892. [DOI: 10.1039/d1cc06543b] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ionic liquids (ILs) are becoming a revolutionary synthesis medium for inorganic nanomaterials, permitting more efficient, safer and environmentally benign preparation of high quality products. A smart combination of ILs and...
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14
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Li Z, Morales-Collazo O, Chrostowski R, Brennecke JF, Mangolini F. In situ nanoscale evaluation of pressure-induced changes in structural morphology of phosphonium phosphate ionic liquid at single-asperity contacts. RSC Adv 2021; 12:413-419. [PMID: 35424509 PMCID: PMC8978665 DOI: 10.1039/d1ra08026a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Accepted: 12/13/2021] [Indexed: 11/21/2022] Open
Abstract
In this work, we perform atomic force microscopy (AFM) experiments to evaluate in situ the dependence of the structural morphology of trihexyltetradecylphosphonium bis(2-ethylhexyl) phosphate ([P6,6,6,14][DEHP]) ionic liquid (IL) on applied pressure. The experimental results obtained upon sliding a diamond-like-carbon-coated silicon AFM tip on mechanically polished steel at an applied pressure up to 5.5 ± 0.3 GPa indicate a structural transition of confined [P6,6,6,14][DEHP] molecules. This pressure-induced morphological change of [P6,6,6,14][DEHP] IL leads to the generation of a lubricious, solid-like interfacial layer, whose growth rate increases with applied pressure and temperature. The structural variation of [P6,6,6,14][DEHP] IL is proposed to derive from the well-ordered layering of the polar groups of ions separated by the apolar tails. These results not only shed new light on the structural organization of phosphonium-based ILs under elevated pressure, but also provide novel insights into the normal pressure-dependent lubrication mechanisms of ILs in general.
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Affiliation(s)
- Zixuan Li
- Texas Materials Institute, The University of Texas at Austin Austin TX 78712 USA .,Materials Science and Engineering Program, The University of Texas at Austin Austin TX 78712 USA
| | - Oscar Morales-Collazo
- McKetta Department of Chemical Engineering, The University of Texas at Austin Austin TX 78712 USA
| | - Robert Chrostowski
- Texas Materials Institute, The University of Texas at Austin Austin TX 78712 USA .,Materials Science and Engineering Program, The University of Texas at Austin Austin TX 78712 USA
| | - Joan F Brennecke
- McKetta Department of Chemical Engineering, The University of Texas at Austin Austin TX 78712 USA
| | - Filippo Mangolini
- Texas Materials Institute, The University of Texas at Austin Austin TX 78712 USA .,Walker Department of Mechanical Engineering, The University of Texas at Austin Austin TX 78712 USA
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15
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Sharma S, Ivanov AS, Margulis CJ. A Brief Guide to the Structure of High-Temperature Molten Salts and Key Aspects Making Them Different from Their Low-Temperature Relatives, the Ionic Liquids. J Phys Chem B 2021; 125:6359-6372. [PMID: 34048657 PMCID: PMC8279547 DOI: 10.1021/acs.jpcb.1c01065] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 04/08/2021] [Indexed: 11/23/2022]
Abstract
High-temperature molten salt research is undergoing somewhat of a renaissance these days due to the apparent advantage of these systems in areas related to clean and sustainable energy harvesting and transfer. In many ways, this is a mature field with decades if not already a century of outstanding work devoted to it. Yet, much of this work was done with pioneering experimental and computational setups that lack the current day capabilities of synchrotrons and high-performance-computing systems resulting in deeply entrenched results in the literature that when carefully inspected may require revision. Yet, in other cases, access to isotopically substituted ions make those pioneering studies very unique and prohibitively expensive to carry out nowadays. There are many review articles on molten salts, some of them cited in this perspective, that are simply outstanding and we dare not try to outdo those. Instead, having worked for almost a couple of decades already on their low-temperature relatives, the ionic liquids, this is the perspective article that some of the authors would have wanted to read when embarking on their research journey on high-temperature molten salts. We hope that this will serve as a simple guide to those expanding from research on ionic liquids to molten salts and vice versa, particularly, when looking into their bulk structural features. The article does not aim at being comprehensive but instead focuses on selected topics such as short- and intermediate-range order, the constraints on force field requirements, and other details that make the high- and low-temperature ionic melts in some ways similar but in others diametrically opposite.
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Affiliation(s)
- Shobha Sharma
- Department
of Chemistry, The University of Iowa, Iowa City, Iowa 52242, United States
| | - Alexander S. Ivanov
- Chemical
Sciences Division, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, Tennessee 37830, United States
| | - Claudio J. Margulis
- Department
of Chemistry, The University of Iowa, Iowa City, Iowa 52242, United States
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16
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Dhattarwal HS, Kashyap HK. Unique and generic structural features of cholinium amino acid-based biocompatible ionic liquids. Phys Chem Chem Phys 2021; 23:10662-10669. [PMID: 33908525 DOI: 10.1039/d1cp00937k] [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
Cholinium amino acid-based (Ch-AA) biocompatible ionic liquids (bio-ILs) are synthesized from renewable components and are efficiently used for biomass processing. However, their microscopic structural features that lead to their application as biomass solvents remain undetermined. Herein, we use atomistic simulations to investigate the structures of six different Ch-AA bio-ILs up to the nanometer length scale and demonstrate that, depending on the anion side chain structure, the respective IL exhibits structural ordering at different length scales. All the six Ch-AA bio-ILs investigated here show a generic feature of having a strong hydrogen bonding network between the hydroxyl group of the cholinium cation and the carboxyl group of the amino acid anions. We illustrate that each of these bio-ILs also displays a unique feature. Distinctive intermediate range structural ordering leads to heterogeneity in methioninate- and phenylalaninate-based ILs caused by the anion side chain segregation. Intermediate range ordering is not observed in glutaminate- and glutamate-based ILs because significant anion side chain and backbone interactions hinder the formation of side chain clusters. Interestingly, for the cysteinate-based IL, the side chains do not interact with the backbones and the intermediate range ordering is not observed because of a shorter anionic side chain.
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Affiliation(s)
- Harender S Dhattarwal
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India.
| | - Hemant K Kashyap
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India.
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17
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Nanoscale heterogeneity, hydrogen bonding and their temperature dependence in cholinium phenylalaninate bio-ionic liquid. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.115329] [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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18
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Sarkar S, Maity A, Chakrabarti R. Microscopic structural features of water in aqueous-reline mixtures of varying compositions. Phys Chem Chem Phys 2021; 23:3779-3793. [PMID: 33532810 DOI: 10.1039/d0cp05341d] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Reline, a mixture of urea and choline chloride in a 2 : 1 molar ratio, is one of the most frequently used deep eutectic solvents. Pure reline and its aqueous solution have large scale industrial use. Owing to the presence of active hydrogen bond formation sites, urea and choline cations can disrupt the hydrogen-bonded network in water. However, a quantitative understanding of the microscopic structural features of water in the presence of reline is still lacking. We carry out extensive all-atom molecular dynamics simulations to elucidate the effect of the gradual addition of co-solvents on the microscopic arrangements of water molecules. We consider four aqueous solutions of reline, between 26.3 and 91.4 wt%. A disruption of the local hydrogen-bonded structure in water is observed upon inclusion of urea and choline chloride. The extent of deviation of the water structure from tetrahedrality is quantified using the tetrahedral order parameter (qtet). Our analyses show a monotonic increase in the structural disorder as the co-solvents are added. Increase in the qtet values are observed when highly electro-negative hetero-atoms like nitrogen, oxygen of urea and choline cations are counted as partners of the central water molecules. Further insights are drawn from the characterization of the hydrogen-bonded network in water and we observe the gradual rupturing of water-water hydrogen bonds and their subsequent replacement by the water-urea hydrogen bonds. A negligible contribution from the hydrogen bonds between water and bulky choline cations has also been found. Considering all the constituents as the hydrogen bond partners we calculate the possibility of a successful hydrogen bond formation with a central water molecule. This gives a clear picture of the underlying mechanism of water replacement by urea.
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Affiliation(s)
- Soham Sarkar
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India.
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19
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Malik A, Kashyap HK. Heterogeneity in hydrophobic deep eutectic solvents: SAXS prepeak and local environments. Phys Chem Chem Phys 2021; 23:3915-3924. [DOI: 10.1039/d0cp05407k] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The observation of the prepeak in the simulated total X-ray scattering structure function (S(q)) reveals the presence of intermediate-range structural heterogeneity in hydrophobic deep eutectic solvents.
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Affiliation(s)
- Akshay Malik
- Department of Chemistry
- Indian Institute of Technology Delhi
- Hauz Khas
- India
| | - Hemant K. Kashyap
- Department of Chemistry
- Indian Institute of Technology Delhi
- Hauz Khas
- India
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20
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Dhabal D, Patra T. Molecular simulation of osmometry in aqueous solutions of the BMIMCl ionic liquid: a potential route to force field parameterization of liquid mixtures. Phys Chem Chem Phys 2020; 22:28325-28338. [PMID: 33300529 DOI: 10.1039/d0cp03833d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Despite widespread development and use of ionic liquids (ILs) in both academic and industrial research, computational force fields (FFs) for most of those are not available for a precise description of inter-species interactions in aqueous environments. In the scope of this study, by means of molecular simulations, the osmotic coefficient of an aqueous solution of an IL is calculated and used as a basis to reparameterize popular IL-FFs existing in the literature. We first calculate the osmotic coefficients (at 298.15 K and 1 atm pressure) of aqueous solutions of 1-butyl-3-methylimidazolium chloride (BMIMCl), a generic IL, popularly used in biomass processing and the subsequent conversion to value-added intermediates. The performance of two popular atomic, nonpolarizable FFs developed for BMIMCl, one by Lopes, Pádua, and coworkers (FF-LP) and the other by Sambasivarao, Acevedo, and coworkers (FF-SA), when mixed with the SPC/E water model, is tested with respect to their ability to reproduce the experimental osmotic coefficient data. Interestingly, the osmotic coefficient is found to be increasing with a gradual increase in IL molality within the concentration range of our investigation, which is contrary to the experimental trend reported in the literature for the same IL-water mixture. Henceforth, necessary corrections to the nonbonded ion-ion and ion-water interactions are made to match the experimental osmotic coefficient. To further assess the reliability of the new FF, we extensively explore the thermodynamic (density, isothermal compressibility, and thermal expansion coefficient), dynamic (diffusivity and viscosity), and association/dissociation properties (rationalized with the help of radial distribution functions) with both the original and reparameterized FF for a wider range of concentrations up to a molality of 18.50 mol kg-1. The calculated quantities are compared against experimental data wherever available. The modified FF parameters exhibit significant improvements in terms of its ability to match experimental solution properties, such as density, viscosity, association/dissociation, etc. We report that excessive dissociation of BMIMCl in water is responsible for the shortcomings observed in the original FFs and improved prediction of physicochemical properties could be achieved using the modified FFs.
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Affiliation(s)
- Debdas Dhabal
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
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21
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Zhao M, Wu B, Castner EW. Mixtures of octanol and an ionic liquid: Structure and transport. J Chem Phys 2020; 153:214501. [DOI: 10.1063/5.0031989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Man Zhao
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, USA
| | - Boning Wu
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, USA
| | - Edward W. Castner
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, USA
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22
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Knudtzon MN, Blank DA. Photodetachment and Electron Dynamics in 1-Butyl-1-methyl-pyrrolidinium Dicyanamide. J Phys Chem B 2020; 124:9144-9153. [PMID: 32955885 DOI: 10.1021/acs.jpcb.0c06508] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The ultrafast transient absorption spectrum of 1-butyl-1-methyl-pyrrolidinium dicyanamide, [Pyr1,4+][DCA-], was measured in the visible and near-infrared (IR) spectral regions. Excitation of the liquid at 4.6 eV created initially delocalized and highly reactive electrons that either geminately recombined (69%) or localized onto a cavity with a time constant of ∼300 fs. Electron localization was reflected in the evolution of the TA spectrum and the time-dependent loss of reactivity with a dichloromethane quencher. The delocalized initial state and spectrum of the free electrons were consistent with computational predictions by Xu and Margulis [ J. Phys. Chem. B, 2015, 119, 532-542] on excess electrons in [Pyr1,4+][DCA-]. The computational study considered two possible localization mechanisms for excess electrons, localization on ions, and localization on cavities. In the case of photogenerated electron-hole pairs, the results presented here demonstrate localization to cavities as the dominant channel. Following localization onto a cavity, the free electrons underwent solvation and loss of reactivity with the quencher with rates that slowed in time. The dynamics were similar to an analogous prior study on the related liquid [Pyr1,x+][NTf2-]. One significant difference was the larger yield of free electrons from photoexcitation of [Pyr1,4+][DCA-]. This was found to primarily reflect more efficient localization onto cavities rather than a slower geminate recombination rate.
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Affiliation(s)
- Meghan N Knudtzon
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - David A Blank
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
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23
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Wang YL, Li B, Sarman S, Mocci F, Lu ZY, Yuan J, Laaksonen A, Fayer MD. Microstructural and Dynamical Heterogeneities in Ionic Liquids. Chem Rev 2020; 120:5798-5877. [PMID: 32292036 PMCID: PMC7349628 DOI: 10.1021/acs.chemrev.9b00693] [Citation(s) in RCA: 192] [Impact Index Per Article: 48.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Indexed: 12/11/2022]
Abstract
Ionic liquids (ILs) are a special category of molten salts solely composed of ions with varied molecular symmetry and charge delocalization. The versatility in combining varied cation-anion moieties and in functionalizing ions with different atoms and molecular groups contributes to their peculiar interactions ranging from weak isotropic associations to strong, specific, and anisotropic forces. A delicate interplay among intra- and intermolecular interactions facilitates the formation of heterogeneous microstructures and liquid morphologies, which further contributes to their striking dynamical properties. Microstructural and dynamical heterogeneities of ILs lead to their multifaceted properties described by an inherent designer feature, which makes ILs important candidates for novel solvents, electrolytes, and functional materials in academia and industrial applications. Due to a massive number of combinations of ion pairs with ion species having distinct molecular structures and IL mixtures containing varied molecular solvents, a comprehensive understanding of their hierarchical structural and dynamical quantities is of great significance for a rational selection of ILs with appropriate properties and thereafter advancing their macroscopic functionalities in applications. In this review, we comprehensively trace recent advances in understanding delicate interplay of strong and weak interactions that underpin their complex phase behaviors with a particular emphasis on understanding heterogeneous microstructures and dynamics of ILs in bulk liquids, in mixtures with cosolvents, and in interfacial regions.
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Affiliation(s)
- Yong-Lei Wang
- Department
of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Bin Li
- School
of Chemical Engineering and Technology, Sun Yat-sen University, Zhuhai 519082, P. R. China
| | - Sten Sarman
- Department
of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Francesca Mocci
- Department
of Chemical and Geological Sciences, University
of Cagliari, I-09042 Monserrato, Italy
| | - Zhong-Yuan Lu
- State
Key Laboratory of Supramolecular Structure and Materials, Institute
of Theoretical Chemistry, Jilin University, Changchun 130021, P. R. China
| | - Jiayin Yuan
- Department
of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Aatto Laaksonen
- Department
of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden
- State
Key Laboratory of Materials-Oriented and Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China
- Centre of
Advanced Research in Bionanoconjugates and Biopolymers, Petru Poni Institute of Macromolecular Chemistry Aleea Grigore Ghica-Voda, 41A, 700487 Iasi, Romania
- Department
of Engineering Sciences and Mathematics, Division of Energy Science, Luleå University of Technology, SE-97187 Luleå, Sweden
| | - Michael D. Fayer
- Department
of Chemistry, Stanford University, Stanford, California 94305, United States
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24
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Zhang G, Zhu H, Chen J, Chen M, Kalwarczyk T, Hołyst R, Li H, Hao J. Self-Stabilized Giant Aggregates in Water from Room-Temperature Ionic Liquids with an Asymmetric Polar-Apolar-Polar Architecture. J Phys Chem B 2020; 124:4651-4660. [PMID: 32383605 DOI: 10.1021/acs.jpcb.0c02283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We report the assembly of four imidazolium bromides, each of which bears a naphthyl on one side of the imidazolium cation and a branched alkyl chain on the other. This design creates a new type of amphiphilic ionic liquid with an apolar-polar-apolar structure and a low melting point (mp, <-20 °C), which has not been achieved by reported counterparts bearing linear alkyl chains. In solvent-free states, microphase segregation occurs where polar and apolar domains arrange bicontinuously as proved by molecular dynamics (MD) simulations. When dispersed in water, self-stabilized giant aggregates formed with ultrahigh colloidal stability (up to years). MD simulations provide clues of discrete bicontinuous phases within the giant aggregates. These newly discovered self-assemblies provide a heterogeneous reservoir that can accommodate guest molecules including the highly apolar fullerene C60, paving the way for a wide range of potential applications.
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Affiliation(s)
- Geping Zhang
- Key Laboratory of Colloid and Interface Chemistry & Key Laboratory of Special Aggregated Materials, Shandong University, Ministry of Education, Jinan 250100, China
| | - Hongxia Zhu
- Key Laboratory of Colloid and Interface Chemistry & Key Laboratory of Special Aggregated Materials, Shandong University, Ministry of Education, Jinan 250100, China.,School of Light Industry and Engineering, Qilu University of Technology (Shandong Academy of Science), Jinan 250353, China
| | - Jingfei Chen
- Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266061, China
| | - Mengjun Chen
- Key Laboratory of Colloid and Interface Chemistry & Key Laboratory of Special Aggregated Materials, Shandong University, Ministry of Education, Jinan 250100, China.,School of Qilu Transportation, Shandong University, Jinan 250353, China
| | - Tomasz Kalwarczyk
- Department III, Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Robert Hołyst
- Department III, Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Hongguang Li
- Key Laboratory of Colloid and Interface Chemistry & Key Laboratory of Special Aggregated Materials, Shandong University, Ministry of Education, Jinan 250100, China
| | - Jingcheng Hao
- Key Laboratory of Colloid and Interface Chemistry & Key Laboratory of Special Aggregated Materials, Shandong University, Ministry of Education, Jinan 250100, China
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25
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Wang YL, Li B, Laaksonen A, Yuan J. The Effect of Phenyl Substitutions on Microstructures and Dynamics of Tetraalkylphosphonium Bis(trifluoro- methylsulfonyl)imide Ionic Liquids. Chemphyschem 2020; 21:1202-1214. [PMID: 32181955 DOI: 10.1002/cphc.201901206] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Revised: 02/24/2020] [Indexed: 01/15/2023]
Abstract
Extensive atomistic simulations demonstrated that a gradual substitution of hexyl chains with phenyl groups in tetraalkylphosphonium cations results in remarkable changes in hydrogen bonding interactions, liquid structures and scattering structural functions, and rotational dynamics of hexyl chains and phenyl groups in tetraalkylphosphonium bis(trifluoromethylsulfonyl)imide ionic liquids. Hydrogen donor sites in hexyl chains present competitive characteristics with those in phenyl groups in coordinating anions, as well as their continuous and intermittent hydrogen bonding dynamics. Cation-cation and anion-anion spatial correlations show concomitant shift to short distances with decreased peak intensities with variations of cation structures, whereas cation-anion correlations have a distinct shift to large radial distances due to decreased associations of anions with neighboring cations. These microstructural changes are qualitatively manifested in shifts of prominent peaks for prevalent charge alternations and adjacency correlations between ion species in scattering structural functions. Meanwhile, rotational dynamics of hexyl chains speed up, which, in turn, slow down rotations of phenyl groups, whereas anions exhibit imperceptible changes in their rotational dynamics. These computational results are intrinsically correlated with conformational flexibilities, molecular sizes, and steric hindrance effects of phenyl groups in comparison with hexyl chains, and constrained distributions of anions around cations in heterogeneous ionic environments.
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Affiliation(s)
- Yong-Lei Wang
- Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91, Stockholm, Sweden
| | - Bin Li
- School of Chemical Engineering and Technology, Sun Yat-sen University, Zhuhai, 519082, P. R. China
| | - Aatto Laaksonen
- Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91, Stockholm, Sweden.,Centre of Advanced Research in Bionanoconjugates and Biopolymers, Petru Poni Institute of Macromolecular Chemistry Aleea Grigore Ghica-Voda, 41A, 700487, Iasi, Romania
| | - Jiayin Yuan
- Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91, Stockholm, Sweden
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26
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Shimizu K, Hisamitsu S, Yanai N, Kimizuka N, Canongia Lopes JN. Photon Upconversion in TTA-Inducing Ionic Liquids: Pinpointing the Role of IL Nanostructured Media Using MD Simulations. J Phys Chem B 2020; 124:3137-3144. [PMID: 32203661 DOI: 10.1021/acs.jpcb.0c00768] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The use of task-specific chromophoric ionic liquids as energy transfer media in triplet-triplet annihilation photon upconversion (TTA-UC) processes has produced several examples of systems with signifficantly enhanced performances. In this work, we use molecular dynamics simulations to probe the relation between the nanostructure of chromophoric ionic liquids and their ability to achieve high TTA-UC quantum yields. The existing atomistic and systematic force fields commonly used to model different ionic liquids are extended to include substituted anthracene moieties, thus allowing the modeling of several chromophoric ionic liquids. The simulation results show that the polar network of the ionic liquids can orient the anthracene moieties within the nonpolar domains preventing direct contacts between them but allowing orientations at the optimal distance for triplet energy migration.
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Affiliation(s)
- Karina Shimizu
- Centro de Química Estrutural, Departamento de Engenharia Química, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal
| | - Shota Hisamitsu
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Center for Molecular Systems (CMS), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Nobuhiro Yanai
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Center for Molecular Systems (CMS), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan.,JST-PRESTO, Honcho 4-1-8, Kawaguchi, Saitama 332-0012, Japan
| | - Nobuo Kimizuka
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Center for Molecular Systems (CMS), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
| | - José N Canongia Lopes
- Centro de Química Estrutural, Departamento de Engenharia Química, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal
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27
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Kaestner P, Strehmel V. Synthesis of ionic polymers by free radical polymerization using aprotic trimethylsilylmethyl‐substituted monomers. JOURNAL OF POLYMER SCIENCE 2020. [DOI: 10.1002/pol.20190310] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Pia Kaestner
- Department of ChemistryNiederrhein University of Applied Sciences, Institute for Coatings and Surface Chemistry Krefeld Germany
| | - Veronika Strehmel
- Department of ChemistryNiederrhein University of Applied Sciences, Institute for Coatings and Surface Chemistry Krefeld Germany
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28
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Wu F, Sharma S, Roy S, Halstenberg P, Gallington LC, Mahurin SM, Dai S, Bryantsev VS, Ivanov AS, Margulis CJ. Temperature Dependence of Short and Intermediate Range Order in Molten MgCl2 and Its Mixture with KCl. J Phys Chem B 2020; 124:2892-2899. [DOI: 10.1021/acs.jpcb.0c00745] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Fei Wu
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242, United States
| | - Shobha Sharma
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242, United States
| | - Santanu Roy
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Phillip Halstenberg
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Leighanne C. Gallington
- X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, United States
| | - Shannon M. Mahurin
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Sheng Dai
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Vyacheslav S. Bryantsev
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Alexander S. Ivanov
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Claudio J. Margulis
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242, United States
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29
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Reddy TDN, Mallik BS. Structure and Conformational Response of Pure and Lithium-Doped Ionic Liquids to Pressure Alterations from Molecular Dynamics Simulations. J Phys Chem B 2020; 124:2436-2449. [DOI: 10.1021/acs.jpcb.9b10530] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Th. Dhileep N. Reddy
- Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi-502285, Sangareddy, India
| | - Bhabani S. Mallik
- Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi-502285, Sangareddy, India
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30
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Boaz NC, Smigla EL, Stippich C, Voss C, Mauro NA. X-ray scattering investigation of ion aggregation in imidazolium-based ionic liquids upon doping with lithium, sodium, potassium, rubidium and cesium salts. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.112540] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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31
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Kaur S, Gupta A, Kashyap HK. How Hydration Affects the Microscopic Structural Morphology in a Deep Eutectic Solvent. J Phys Chem B 2020; 124:2230-2237. [DOI: 10.1021/acs.jpcb.9b11753] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Supreet Kaur
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Aditya Gupta
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Hemant K. Kashyap
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
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32
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Warr GG, Atkin R. Solvophobicity and amphiphilic self-assembly in neoteric and nanostructured solvents. Curr Opin Colloid Interface Sci 2020. [DOI: 10.1016/j.cocis.2019.12.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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33
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Susceptibility of biomembrane structure towards amphiphiles, ionic liquids, and deep eutectic solvents. ADVANCES IN BIOMEMBRANES AND LIPID SELF-ASSEMBLY 2020. [DOI: 10.1016/bs.abl.2020.02.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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34
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Sharma S, Dhattarwal HS, Kashyap HK. Molecular dynamics investigation of electrostatic properties of pyrrolidinium cation based ionic liquids near electrified carbon electrodes. J Mol Liq 2019. [DOI: 10.1016/j.molliq.2019.111269] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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35
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Mesoscopic structural organization in fluorinated pyrrolidinium-based room temperature ionic liquids. J Mol Liq 2019. [DOI: 10.1016/j.molliq.2019.111110] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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36
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Kaur S, Malik A, Kashyap HK. Anatomy of Microscopic Structure of Ethaline Deep Eutectic Solvent Decoded through Molecular Dynamics Simulations. J Phys Chem B 2019; 123:8291-8299. [DOI: 10.1021/acs.jpcb.9b06624] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Supreet Kaur
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Akshay Malik
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Hemant K. Kashyap
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
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37
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Zhao M, Wu B, Lall-Ramnarine SI, Ramdihal JD, Papacostas KA, Fernandez ED, Sumner RA, Margulis CJ, Wishart JF, Castner EW. Structural analysis of ionic liquids with symmetric and asymmetric fluorinated anions. J Chem Phys 2019; 151:074504. [PMID: 31438705 DOI: 10.1063/1.5111643] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Ionic liquids (ILs) with relatively low viscosities and broad windows of electrochemical stability are often constructed by pairing asymmetric cations with bisfluorosulfonylimide (FSI-) or bistriflimide (NTf2 -) anions. In this work, we systematically studied the structures of ILs with these anions and related perfluorobis-sulfonylimide anions with asymmetry and/or longer chains: (fluorosulfonyl)(trifluoromethylsulfonyl)imide (BSI0,1 -), bis(pentafluoroethylsulfonyl)imide (BETI-), and (trifluoromethylsulfonyl) (nonafluorobutylsulfonyl)imide (BSI1,4 -) using high energy X-ray scattering and molecular dynamics simulation methods. 1-alkyl-3-methylimidazolium cations with shorter (ethyl, Im2,1 +) and longer (octyl, Im1,8 +) hydrocarbon chains were selected to examine how the sizes of nonpolar hydrocarbon and fluorous chains affect IL structures and properties. In comparison with these, we also computationally explored the structure of ionic liquids with anions having longer fluorinated tails.
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Affiliation(s)
- Man Zhao
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, USA
| | - Boning Wu
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, USA
| | - Sharon I Lall-Ramnarine
- Chemistry Department, Queensborough Community College of the City University of New York, Bayside, New York 11364, USA
| | - Jasodra D Ramdihal
- Chemistry Department, Queensborough Community College of the City University of New York, Bayside, New York 11364, USA
| | - Kristina A Papacostas
- Chemistry Department, Queensborough Community College of the City University of New York, Bayside, New York 11364, USA
| | - Eddie D Fernandez
- Chemistry Department, Queensborough Community College of the City University of New York, Bayside, New York 11364, USA
| | - Rawlric A Sumner
- Chemistry Department, Queensborough Community College of the City University of New York, Bayside, New York 11364, USA
| | - Claudio J Margulis
- Department of Chemistry, The University of Iowa, Iowa City, Iowa 52242, USA
| | - James F Wishart
- Chemistry Division, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - Edward W Castner
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, USA
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38
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Kaur S, Shobhna, Kashyap HK. Insights Gained from Refined Force-Field for Pure and Aqueous Ethylene Glycol through Molecular Dynamics Simulations. J Phys Chem B 2019; 123:6543-6553. [DOI: 10.1021/acs.jpcb.9b03950] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Supreet Kaur
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Shobhna
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Hemant K. Kashyap
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
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39
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Fleshman AM, Mauro NA. Temperature-dependent structure and transport of ionic liquids with short-and intermediate-chain length pyrrolidinium cations. J Mol Liq 2019. [DOI: 10.1016/j.molliq.2019.01.108] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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40
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Mackoy T, Mauro NA, Wheeler RA. Temperature Dependence of Static Structure Factor Peak Intensities for a Pyrrolidinium-Based Ionic Liquid. J Phys Chem B 2019; 123:1672-1678. [PMID: 30673263 DOI: 10.1021/acs.jpcb.9b00449] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Static structure factors ( S( q)) for many ionic liquids show low-wavenumber peaks whose intensities increase with increasing temperature. The greater peak intensities might seem to imply increasing intermediate-range order with increasing temperature. Molecular dynamics (MD) simulations for a representative ionic liquid, 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide (C4C1pyrrTFSI), were used to calculate S( q) and partial S( q) (cation-cation, anion-anion, and cation-anion) at 298, 363, and 500 K. S( q) and partial S( q) were further decomposed into positive and negative components (which each indicate structural ordering) by separately summing positive and negative Fourier transform summands. Increasing temperature causes the negative components of each partial S( q) to decrease in magnitude more than the positive components, causing the total S( q) to increase in magnitude. Thus, structural ordering with periodicities corresponding to observed peaks in S( q) does not increase but instead decoheres with increasing temperature, even though S( q) peak heights increase. Fourier transform summands also show where in real space the positive and negative component contributions to S( q) change when the temperature increases. This new, detailed analysis based on Fourier transform summands comprising S( q) argues for great caution when interpreting S( q) intensities and highlights the value of simulations as a complement to X-ray (or neutron) scattering experiments.
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Affiliation(s)
- Travis Mackoy
- Department of Chemistry and Biochemistry , Northern Illinois University , DeKalb , Illinois 60115 , United States
| | - Nicholas A Mauro
- Department of Physics , St. Norbert College , De Pere , Wisconsin 54115 , United States
| | - Ralph A Wheeler
- Department of Chemistry and Biochemistry , Northern Illinois University , DeKalb , Illinois 60115 , United States
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41
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Gupta A, Kaur S, Kashyap HK. How Water Permutes the Structural Organization and Microscopic Dynamics of Cholinium Glycinate Biocompatible Ionic Liquid. J Phys Chem B 2019; 123:2057-2069. [DOI: 10.1021/acs.jpcb.8b10235] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Aditya Gupta
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Supreet Kaur
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Hemant K. Kashyap
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
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42
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Kumari P, Shobhna, Kaur S, Kashyap HK. Influence of Hydration on the Structure of Reline Deep Eutectic Solvent: A Molecular Dynamics Study. ACS OMEGA 2018; 3:15246-15255. [PMID: 31458186 PMCID: PMC6644006 DOI: 10.1021/acsomega.8b02447] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Accepted: 10/23/2018] [Indexed: 05/28/2023]
Abstract
In this article, we have performed an all-atom molecular dynamics simulation study to investigate the influence of water on the molecular level arrangement of reline deep eutectic solvent for different hydration levels ranging from 3.4 to 58.1 wt % of water and complemented the observations of recently measured neutron scattering experimental data. This study is particularly important because water is being introduced as a second hydrogen bond donor/acceptor in reline, wherein the structure is primarily governed by hydrogen bonding and electrostatic interactions. We have analyzed the simulated X-ray scattering structure functions, their partial components, and hydrogen bonding interactions to understand the effects of water on various intermolecular interactions in reline-water mixtures. It is observed that at lower hydration level, reline structure is qualitatively retained. At higher hydration level, most water molecules preferentially solvate chloride anions and ammonium group of choline cations mostly impacting choline-choline, choline-chloride, and chloride-chloride interactions. The present study reveals that at and above 41 wt % of water, the molecular arrangement of reline drastically changes and set to transition from reline to an aqueous solution of reline components with further increase in the hydration level. Hydrogen bond analysis reveals the presence of strong chloride-water H-bonding interaction, which gradually replaces choline-chloride and urea-chloride hydrogen bondings as the hydration level in the mixture increases.
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Affiliation(s)
- Pratibha Kumari
- Department of Chemistry, Indian
Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Shobhna
- Department of Chemistry, Indian
Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Supreet Kaur
- Department of Chemistry, Indian
Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Hemant K. Kashyap
- Department of Chemistry, Indian
Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
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43
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Wu B, Kuroda K, Takahashi K, Castner EW. Structural analysis of zwitterionic liquids vs. homologous ionic liquids. J Chem Phys 2018; 148:193807. [PMID: 30307210 DOI: 10.1063/1.5010983] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Zwitterionic liquids (Zw-ILs) have been developed that are homologous to monovalent ionic liquids (ILs) and show great promise for controlled dissolution of cellulosic biomass. Using both high energy X-ray scattering and atomistic molecular simulations, this article compares the bulk liquid structural properties for novel Zw-ILs with their homologous ILs. It is shown that the significant localization of the charges on Zw-ILs leads to charge ordering similar to that observed for conventional ionic liquids with monovalent anions and cations. A low-intensity first sharp diffraction peak in the liquid structure factor S(q) is observed for both the Zw-IL and the IL. This is unexpected since both the Zw-IL and IL have a 2-(2-methoxyethoxy)ethyl (diether) functional group on the cationic imidazolium ring and ether functional groups are known to suppress this peak. Detailed analyses show that this intermediate range order in the liquid structure arises for slightly different reasons in the Zw-IL vs. the IL. For the Zw-IL, the ether tails in the liquid are shown to aggregate into nanoscale domains.
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Affiliation(s)
- Boning Wu
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, USA
| | - Kosuke Kuroda
- Institute of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
| | - Kenji Takahashi
- Institute of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
| | - Edward W Castner
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, USA
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44
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Structures of binary mixtures of ionic liquid 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide with primary alcohols: The role of hydrogen-bonding. J Mol Liq 2018. [DOI: 10.1016/j.molliq.2018.03.124] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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45
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Lo Celso F, Triolo A, Gontrani L, Russina O. Communication: Anion-specific response of mesoscopic organization in ionic liquids upon pressurization. J Chem Phys 2018; 148:211102. [DOI: 10.1063/1.5036588] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Fabrizio Lo Celso
- Dipartimento di Fisica e Chimica, Università di Palermo, Palermo, Italy
- Laboratorio Liquidi Ionici, Istituto Struttura della Materia, CNR (ISM-CNR), Rome, Italy
| | - Alessandro Triolo
- Laboratorio Liquidi Ionici, Istituto Struttura della Materia, CNR (ISM-CNR), Rome, Italy
| | - Lorenzo Gontrani
- Dipartimento di Chimica, Sapienza University, P. le Aldo Moro 5, Roma, Italy
| | - Olga Russina
- Dipartimento di Chimica, Sapienza University, P. le Aldo Moro 5, Roma, Italy
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46
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Kapoor U, Shah JK. Effect of molecular solvents of varying polarity on the self-assembly of 1-n-dodecyl-3-methylimidazolium octylsulfate ionic liquid. JOURNAL OF THEORETICAL & COMPUTATIONAL CHEMISTRY 2018. [DOI: 10.1142/s0219633618400047] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Large-scale molecular dynamics simulations consisting of more than 88,000–106,000 atoms for approximately 250 ns (including equilibration and production) were conducted to assess the effect of polar, nonpolar and amphiphilic molecular solvents on the nanoscale structuring of 1-[Formula: see text]-dodecyl-3-methylimidazolium [C[Formula: see text]mim] octylsulfate [C8SO4] ionic liquid (IL). Water [H2O], [Formula: see text]-octane [C8H[Formula: see text]] and 1-octanol [C8H[Formula: see text]OH] are employed as examples of polar, nonpolar, and amphiphilic molecules, respectively. The results indicate that each of these molecular solvents modify the nanosegregation behavior of the ionic liquid in a unique way. Water induces a high order of structuring of the ionic liquid as indicated by extremely high nematic order parameter for the system. In addition, the morphology of the neat ionic liquid is transformed from layer-like to that of bilayer-like in which the polar and nonpolar domains alternate. The presence of water also causes the stretching of the nonpolar domain, thus, increasing its size. At the concentration examined in this work, [Formula: see text]-octane is found to be only partially miscible with the ionic liquid. The polar network is maintained; however, the continuous cationic nonpolar domain is split into multiple domains. [Formula: see text]-octane is accommodated in the ionic liquid nonpolar domain. Similarly, the amphiphilicity of 1-octanol leads to an increase in the number of cationic as well as anionic domains. The overall nonpolar domain length, however, remains nearly identical to that found for the pure ionic liquid. Additional characterization of structural features of the three systems is discussed in terms of one-dimensional number densities, nematic order parameters for the overall systems and their components and structure factors.
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Affiliation(s)
- Utkarsh Kapoor
- School of Chemical Engineering, Oklahoma State University, Stillwater, OK 74078, USA
| | - Jindal K. Shah
- School of Chemical Engineering, Oklahoma State University, Stillwater, OK 74078, USA
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47
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Cosby T, Vicars Z, Heres M, Tsunashima K, Sangoro J. Dynamic and structural evidence of mesoscopic aggregation in phosphonium ionic liquids. J Chem Phys 2018; 148:193815. [DOI: 10.1063/1.5009765] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- T. Cosby
- Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Z. Vicars
- Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - M. Heres
- Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - K. Tsunashima
- Department of Applied Chemistry and Biochemistry, National Institute of Technology, Wakayama College, Wakayama 644-0023, Japan
| | - J. Sangoro
- Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, USA
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48
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Kaur S, Kashyap HK. Unusual Temperature Dependence of Nanoscale Structural Organization in Deep Eutectic Solvents. J Phys Chem B 2018; 122:5242-5250. [DOI: 10.1021/acs.jpcb.8b02378] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Supreet Kaur
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Hemant K. Kashyap
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
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49
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50
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Ionic Liquids Treated within the Grand Canonical Adaptive Resolution Molecular Dynamics Technique. COMPUTATION 2018. [DOI: 10.3390/computation6010023] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We use the Grand Canonical Adaptive Resolution Molecular Dynamics Technique (GC-AdResS) to examine the essential degrees of freedom necessary for reproducing the structural properties of the imidazolium class of ionic liquids. In this technique, the atomistic details are treated as an open sub-region of the system while the surrounding environment is modelled as a generic coarse-grained model. We systematically characterize the spatial quantities such as intramolecular, intermolecular radial distribution functions, other structural and orientational properties of ILs. The spatial quantities computed in an open sub-region of the system are in excellent agreement with the equivalent quantities calculated in a full atomistic simulation, suggesting that the atomistic degrees of freedom outside the sub-region are negligible. The size of the sub-region considered in this study is 2 nm, which is essentially the size of a few ions. Insight from the study suggests that a higher degree of spatial locality seems to play a crucial role in characterizing the properties of imidazolium based ionic liquids.
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