1
|
Lass M, Kenter T, Plessl C, Brehm M. Characterizing Microheterogeneity in Liquid Mixtures via Local Density Fluctuations. ENTROPY (BASEL, SWITZERLAND) 2024; 26:322. [PMID: 38667876 PMCID: PMC11049288 DOI: 10.3390/e26040322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Revised: 04/04/2024] [Accepted: 04/05/2024] [Indexed: 04/28/2024]
Abstract
We present a novel approach to characterize and quantify microheterogeneity and microphase separation in computer simulations of complex liquid mixtures. Our post-processing method is based on local density fluctuations of the different constituents in sampling spheres of varying size. It can be easily applied to both molecular dynamics (MD) and Monte Carlo (MC) simulations, including periodic boundary conditions. Multidimensional correlation of the density distributions yields a clear picture of the domain formation due to the subtle balance of different interactions. We apply our approach to the example of force field molecular dynamics simulations of imidazolium-based ionic liquids with different side chain lengths at different temperatures, namely 1-ethyl-3-methylimidazolium chloride, 1-hexyl-3-methylimidazolium chloride, and 1-decyl-3-methylimidazolium chloride, which are known to form distinct liquid domains. We put the results into the context of existing microheterogeneity analyses and demonstrate the advantages and sensitivity of our novel method. Furthermore, we show how to estimate the configuration entropy from our analysis, and we investigate voids in the system. The analysis has been implemented into our program package TRAVIS and is thus available as free software.
Collapse
Affiliation(s)
- Michael Lass
- Faculty of Computer Science, Electrical Engineering and Mathematics, Department of Computer Science, Paderborn University, Warburger Straße 100, 33098 Paderborn, Germany; (M.L.); (T.K.); (C.P.)
| | - Tobias Kenter
- Faculty of Computer Science, Electrical Engineering and Mathematics, Department of Computer Science, Paderborn University, Warburger Straße 100, 33098 Paderborn, Germany; (M.L.); (T.K.); (C.P.)
| | - Christian Plessl
- Faculty of Computer Science, Electrical Engineering and Mathematics, Department of Computer Science, Paderborn University, Warburger Straße 100, 33098 Paderborn, Germany; (M.L.); (T.K.); (C.P.)
| | - Martin Brehm
- Faculty of Science, Department of Chemistry, Paderborn University, Warburger Straße 100, 33098 Paderborn, Germany
| |
Collapse
|
2
|
Ma L, Zhong Z, Hu J, Qing L, Jiang J. Long-Lived Weak Ion Pairs in Ionic Liquids: An Insight from All-Atom Molecular Dynamics Simulations. J Phys Chem B 2023. [PMID: 37262343 DOI: 10.1021/acs.jpcb.3c01559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The microstructure and local dynamics of ions in room-temperature ionic liquids (RTILs) have drawn a lot of attention due to their extensive potential applications in numerous fields. It is well-known that the widely used definitions of ion pairs (IPs) cannot reflect the full picture of RTILs. In this study, we find a universal residence time (τMR), which is regardless of the number of counterions in the first solvation shell in RTILs. Inspired by this, we propose a weak IP (WIP) model from a spatiotemporal perspective and demonstrate that the WIPs are long-lived and that their lifetimes obey a log-normal distribution, which is different from the literature. In addition, the electrostatic interactions are the main factors in the formation of WIPs, and the reorientations of ions are vital to the ruptures of WIPs. This research provides a new perspective for understanding the microstructural and dynamical properties of RTILs.
Collapse
Affiliation(s)
- Linbo Ma
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Zhixuan Zhong
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Junbao Hu
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Leying Qing
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Jian Jiang
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| |
Collapse
|
3
|
Roos E, Sebastiani D, Brehm M. A force field for bio-polymers in ionic liquids (BILFF) - part 2: cellulose in [EMIm][OAc]/water mixtures. Phys Chem Chem Phys 2023; 25:8755-8766. [PMID: 36897117 DOI: 10.1039/d2cp05636d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
We present the extension of our force field BILFF (Bio-Polymers in Ionic Liquids Force Field) to the bio-polymer cellulose. We already published BILFF parameters for mixtures of ionic liquid 1-ethyl-3-methylimidazolium acetate ([EMIm][OAc]) with water. Our all-atom force field focuses on a quantitative reproduction of the hydrogen bonds in the complex mixture of cellulose, [EMIm]+, [OAc]- and water when compared to reference ab initio molecular dynamics (AIMD) simulations. To enhance the sampling, 50 individual AIMD simulations starting from different initial configurations were performed for cellulose in solvent instead of one long simulation, and the resulting averages were used for force field optimization. All cellulose force field parameters were iteratively adjusted starting from the literature force field of W. Damm et al. We were able to obtain a very good agreement with respect to both the microstructure of the reference AIMD simulations and experimental results such as the system density (even at higher temperatures) and the crystal structure. Our new force field allows performing very long simulations of large systems containing cellulose solvated in (aqueous) [EMIm][OAc] with almost ab initio accuracy.
Collapse
Affiliation(s)
- Eliane Roos
- Institut für Chemie - Theoretische Chemie, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz 4, 06120 Halle (Saale), Germany.
| | - Daniel Sebastiani
- Institut für Chemie - Theoretische Chemie, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz 4, 06120 Halle (Saale), Germany.
| | - Martin Brehm
- Institut für Chemie - Theoretische Chemie, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz 4, 06120 Halle (Saale), Germany.
| |
Collapse
|
4
|
Radicke J, Roos E, Sebastiani D, Brehm M, Kressler J. Lactate‐based ionic liquids as chiral solvents for cellulose. JOURNAL OF POLYMER SCIENCE 2022. [DOI: 10.1002/pol.20220687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Julian Radicke
- Department of Chemistry Martin Luther University Halle–Wittenberg Halle (Saale) Germany
| | - Eliane Roos
- Department of Chemistry Martin Luther University Halle–Wittenberg Halle (Saale) Germany
| | - Daniel Sebastiani
- Department of Chemistry Martin Luther University Halle–Wittenberg Halle (Saale) Germany
| | - Martin Brehm
- Department of Chemistry Martin Luther University Halle–Wittenberg Halle (Saale) Germany
| | - Jörg Kressler
- Department of Chemistry Martin Luther University Halle–Wittenberg Halle (Saale) Germany
| |
Collapse
|
5
|
Niemöller H, Blasius J, Hollóczki O, Kirchner B. How do alternative amino acids behave in water? A comparative ab initio molecular dynamics study of solvated α-amino acids and α-amino amidines. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.120282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
6
|
Frömbgen T, Blasius J, Alizadeh V, Chaumont A, Brehm M, Kirchner B. Cluster Analysis in Liquids: A Novel Tool in TRAVIS. J Chem Inf Model 2022; 62:5634-5644. [PMID: 36315975 DOI: 10.1021/acs.jcim.2c01244] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We present a novel cluster analysis implemented in our open-source software TRAVIS and its application to realistic and complex chemical systems. The underlying algorithm is exclusively based on atom distances. Using a two-dimensional model system, we first introduce different cluster analysis functions and their application to single snapshots and trajectories including periodicity and temporal propagation. Using molecular dynamics simulations of pure water with varying system size, we show that our cluster analysis is size-independent. Furthermore, we observe a similar clustering behavior of pure water in classical and ab initio molecular dynamics simulations, showing that our cluster analysis is universal. In order to emphasize the application to more complex systems and mixtures, we additionally apply the cluster analysis to ab initio molecular dynamics simulations of the [C2C1Im][OAc] ionic liquid and its mixture with water. Using that, we show that our cluster analysis is able to analyze the clustering of the individual components in a mixture as well as the clustering of the ionic liquid with water.
Collapse
Affiliation(s)
- Tom Frömbgen
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstraße 4+6, D-53115 Bonn, Germany
| | - Jan Blasius
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstraße 4+6, D-53115 Bonn, Germany
| | - Vahideh Alizadeh
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstraße 4+6, D-53115 Bonn, Germany
| | - Alain Chaumont
- Laboratoire MSM, UMR 7140 CNRS, Institut de Chimie, 4 Rue Blaise Pascal, F-67000 Strasbourg, France
| | - Martin Brehm
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz 4, D-06120 Halle (Saale), Germany
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstraße 4+6, D-53115 Bonn, Germany
| |
Collapse
|
7
|
Bodo E. Modelling biocompatible ionic liquids based on organic acids and amino acids: challenges for computational models and future perspectives. Org Biomol Chem 2021; 19:4002-4013. [PMID: 33978045 DOI: 10.1039/d1ob00011j] [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
In this short review I shall highlight the basic principle and the difficulties that arise in attempting the computational modeling of seemingly simple systems which hide an unexpected complexity. Biocompatible ionic liquids which are based on the coupling of organic or amino acid anions with metabolic cations such as cholinium are the target of this review. These substances have been the subject of intense research activities in the last few years and have attracted the attention of computational chemists. I shall show that the computational description of these substances is far from trivial and requires the use of sophisticated techniques in order to account for a surprisingly rich chemistry that is due to several phenomena such as polarization, charge transfer, proton transfer equilibria and tautomerization reactions.
Collapse
Affiliation(s)
- Enrico Bodo
- Chemistry Department, University of Rome "La Sapienza", P. A. Moro 5, 00185 Rome, Italy.
| |
Collapse
|
8
|
Brehm M, Thomas M. Optimized Atomic Partial Charges and Radii Defined by Radical Voronoi Tessellation of Bulk Phase Simulations. Molecules 2021; 26:1875. [PMID: 33810337 PMCID: PMC8036805 DOI: 10.3390/molecules26071875] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 03/22/2021] [Accepted: 03/24/2021] [Indexed: 12/05/2022] Open
Abstract
We present a novel method for the computation of well-defined optimized atomic partial charges and radii from the total electron density. Our method is based on a two-step radical Voronoi tessellation of the (possibly periodic) system and subsequent integration of the total electron density within each Voronoi cell. First, the total electron density is partitioned into the contributions of each molecule, and subsequently the electron density within each molecule is assigned to the individual atoms using a second set of atomic radii for the radical Voronoi tessellation. The radii are optimized on-the-fly to minimize the fluctuation (variance) of molecular and atomic charges. Therefore, our method is completely free of empirical parameters. As a by-product, two sets of optimized atomic radii are produced in each run, which take into account many specific properties of the system investigated. The application of an on-the-fly interpolation scheme reduces discretization noise in the Voronoi integration. The approach is particularly well suited for the calculation of partial charges in periodic bulk phase systems. We apply the method to five exemplary liquid phase simulations and show how the optimized charges can help to understand the interactions in the systems. Well-known effects such as reduced ion charges below unity in ionic liquid systems are correctly predicted without any tuning, empiricism, or rescaling. We show that the basis set dependence of our method is very small. Only the total electron density is evaluated, and thus, the approach can be combined with any electronic structure method that provides volumetric total electron densities-it is not limited to Hartree-Fock or density functional theory (DFT). We have implemented the method into our open-source software tool TRAVIS.
Collapse
Affiliation(s)
- Martin Brehm
- Institut für Chemie, Martin-Luther-Universität Halle–Wittenberg, von-Danckelmann-Platz 4, D-06120 Halle (Saale), Germany;
| | | |
Collapse
|
9
|
Roos E, Brehm M. A force field for bio-polymers in ionic liquids (BILFF) - part 1: [EMIm][OAc]/water mixtures. Phys Chem Chem Phys 2021; 23:1242-1253. [PMID: 33355320 DOI: 10.1039/d0cp04537c] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We present BILFF, a novel force field for bio-polymers in ionic liquids. In the first part of our study, we introduce optimized force field parameters for mixtures of the ionic liquid (IL) 1-ethyl-3-methylimidazolium acetate ([EMIm][OAc]) with water. This imidazolium-based IL is of particular practical importance as it can dissolve significant amounts of cellulose even at room temperature. An understanding of this dissolution process via molecular dynamics simulations requires a quantitative description of the microscopic structure and the strong hydrogen bonds with a method able of simulating at least several dozen nanoseconds, which is the main aim of our novel force field. To reach this goal, we optimize the force field parameters to reproduce radial, spatial, and combined distribution functions, hydrogen bond lifetimes, diffusion coefficients, and several other quantities from reference ab initio molecular dynamics (AIMD) simulations. Non-trivial effects such as dispersion interactions between the side chains and π-π stacking of the cations are reproduced very well. We further validate the force field by comparison to experimental data such as thermal expansion coefficients, bulk modulus, and density at different temperatures, which yields good agreement and correct trends. No other force field with optimized parameters for mixtures of [EMIm][OAc] and water has been presented in the literature yet. Optimized force field parameters for cellulose and other ILs will be published in upcoming articles.
Collapse
Affiliation(s)
- Eliane Roos
- Institut für Chemie - Theoretische Chemie, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz 4, 06120 Halle (Saale), Germany.
| | - Martin Brehm
- Institut für Chemie - Theoretische Chemie, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz 4, 06120 Halle (Saale), Germany.
| |
Collapse
|
10
|
Araújo JR, de Andrade RB, Batista HJ, Ventura E, do Monte SA. Can a gas phase contact ion pair containing a hydrocarbon carbocation be formed in the ground state? RSC Adv 2021; 11:4221-4230. [PMID: 35424376 PMCID: PMC8694316 DOI: 10.1039/d0ra10523f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 01/11/2021] [Indexed: 11/21/2022] Open
Abstract
So far, no conclusive evidence of a ground-state contact ion-pair containing a hydrocarbon carbocation has been given in the gas phase.
Collapse
Affiliation(s)
- José R. Araújo
- Departamento de Química
- CCEN
- Universidade Federal da Paraíba
- João Pessoa
- Brazil
| | | | - Hélcio J. Batista
- Departamento de Química
- Universidade Federal Rural de Pernambuco
- Recife
- Brazil
| | - Elizete Ventura
- Departamento de Química
- CCEN
- Universidade Federal da Paraíba
- João Pessoa
- Brazil
| | - Silmar A. do Monte
- Departamento de Química
- CCEN
- Universidade Federal da Paraíba
- João Pessoa
- Brazil
| |
Collapse
|
11
|
Weiß M, Brehm M. Exploring Free Energy Profiles of Enantioselective Organocatalytic Aldol Reactions under Full Solvent Influence. Molecules 2020; 25:E5861. [PMID: 33322424 PMCID: PMC7764805 DOI: 10.3390/molecules25245861] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 12/05/2020] [Accepted: 12/08/2020] [Indexed: 12/29/2022] Open
Abstract
We present a computational study on the enantioselectivity of organocatalytic proline-catalyzed aldol reactions between aldehydes in dimethylformamide (DMF). To explore the free energy surface of the reaction, we apply two-dimensional metadynamics on top of ab initio molecular dynamics (AIMD) simulations with explicit solvent description on the DFT level of theory. We avoid unwanted side reactions by utilizing our newly developed hybrid AIMD (HyAIMD) simulation scheme, which adds a simple force field to the AIMD simulation to prevent unwanted bond breaking and formation. Our condensed phase simulation results are able to nicely reproduce the experimental findings, including the main stereoisomer that is formed, and give a correct qualitative prediction of the change in syn:anti product ratio with different substituents. Furthermore, we give a microscopic explanation for the selectivity. We show that both the explicit description of the solvent and the inclusion of entropic effects are vital to a good outcome-metadynamics simulations in vacuum and static nudged elastic band (NEB) calculations yield significantly worse predictions when compared to the experiment. The approach described here can be applied to a plethora of other enantioselective or organocatalytic reactions, enabling us to tune the catalyst or determine the solvent with the highest stereoselectivity.
Collapse
Affiliation(s)
| | - Martin Brehm
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, von-Danckelmann-Platz 4, D-06120 Halle (Saale), Germany;
| |
Collapse
|
12
|
Brehm M, Radicke J, Pulst M, Shaabani F, Sebastiani D, Kressler J. Dissolving Cellulose in 1,2,3-Triazolium- and Imidazolium-Based Ionic Liquids with Aromatic Anions. Molecules 2020; 25:E3539. [PMID: 32748878 PMCID: PMC7435399 DOI: 10.3390/molecules25153539] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 07/29/2020] [Accepted: 07/30/2020] [Indexed: 11/16/2022] Open
Abstract
We present 1,2,3-triazolium- and imidazolium-based ionic liquids (ILs) with aromatic anions as a new class of cellulose solvents. The two anions in our study, benzoate and salicylate, possess a lower basicity when compared to acetate and therefore should lead to a lower amount of N-heterocyclic carbenes (NHCs) in the ILs. We characterize their physicochemical properties and find that all of them are liquids at room temperature. By applying force field molecular dynamics (MD) simulations, we investigate the structure and dynamics of the liquids and find strong and long-lived hydrogen bonds, as well as significant π-π stacking between the aromatic anion and cation. Our ILs dissolve up to 8.5 wt.-% cellulose. Via NMR spectroscopy of the solution, we rule out chain degradation or derivatization, even after several weeks at elevated temperature. Based on our MD simulations, we estimate the enthalpy of solvation and derive a simple model for semi-quantitative prediction of cellulose solubility in ILs. With the help of Sankey diagrams, we illustrate the hydrogen bond network topology of the solutions, which is characterized by competing hydrogen bond donors and acceptors. The hydrogen bonds between cellulose and the anions possess average lifetimes in the nanosecond range, which is longer than found in common pure ILs.
Collapse
Affiliation(s)
- Martin Brehm
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, von-Danckelmann-Platz 4, D-06120 Halle, Germany
| | - Julian Radicke
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, von-Danckelmann-Platz 4, D-06120 Halle, Germany
| | - Martin Pulst
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, von-Danckelmann-Platz 4, D-06120 Halle, Germany
| | - Farzaneh Shaabani
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, von-Danckelmann-Platz 4, D-06120 Halle, Germany
| | - Daniel Sebastiani
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, von-Danckelmann-Platz 4, D-06120 Halle, Germany
| | - Jörg Kressler
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, von-Danckelmann-Platz 4, D-06120 Halle, Germany
| |
Collapse
|
13
|
Brehm M, Thomas M, Gehrke S, Kirchner B. TRAVIS—A free analyzer for trajectories from molecular simulation. J Chem Phys 2020; 152:164105. [DOI: 10.1063/5.0005078] [Citation(s) in RCA: 164] [Impact Index Per Article: 41.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Affiliation(s)
- M. Brehm
- Institut für Chemie, Martin-Luther-Universität Halle–Wittenberg, von-Danckelmann-Platz 4, D-06120 Halle (Saale), Germany
| | - M. Thomas
- Institut für Chemie, Martin-Luther-Universität Halle–Wittenberg, von-Danckelmann-Platz 4, D-06120 Halle (Saale), Germany
| | - S. Gehrke
- Mulliken Center for Theoretical Chemistry, Rheinische Friedrich-Wilhelms-Universität Bonn, Beringstr. 4+6, D-53115 Bonn, Germany
| | - B. Kirchner
- Mulliken Center for Theoretical Chemistry, Rheinische Friedrich-Wilhelms-Universität Bonn, Beringstr. 4+6, D-53115 Bonn, Germany
| |
Collapse
|
14
|
Červinka C, Klajmon M, Štejfa V. Cohesive Properties of Ionic Liquids Calculated from First Principles. J Chem Theory Comput 2019; 15:5563-5578. [DOI: 10.1021/acs.jctc.9b00625] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ctirad Červinka
- Department of Physical Chemistry, University of Chemistry and Technology Prague, Technická 5, CZ-166 28 Prague 6, Czech Republic
| | - Martin Klajmon
- Department of Physical Chemistry, University of Chemistry and Technology Prague, Technická 5, CZ-166 28 Prague 6, Czech Republic
| | - Vojtěch Štejfa
- Department of Physical Chemistry, University of Chemistry and Technology Prague, Technická 5, CZ-166 28 Prague 6, Czech Republic
| |
Collapse
|
15
|
Brehm M, Pulst M, Kressler J, Sebastiani D. Triazolium-Based Ionic Liquids: A Novel Class of Cellulose Solvents. J Phys Chem B 2019; 123:3994-4003. [DOI: 10.1021/acs.jpcb.8b12082] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Martin Brehm
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz 4, D-06120 Halle (Saale), Germany
| | - Martin Pulst
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz 4, D-06120 Halle (Saale), Germany
| | - Jörg Kressler
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz 4, D-06120 Halle (Saale), Germany
| | - Daniel Sebastiani
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz 4, D-06120 Halle (Saale), Germany
| |
Collapse
|
16
|
Gehrke S, Reckien W, Palazzo I, Welton T, Hollóczki O. On the Carbene-Like Reactions of Imidazolium Acetate Ionic Liquids: Can Theory and Experiments Agree? European J Org Chem 2018. [DOI: 10.1002/ejoc.201801050] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Sascha Gehrke
- Mulliken Center for Theoretical Chemistry; University of Bonn; Beringstr. 4+6 Bonn Germany
- Max Planck Institute for Chemical Energy Conversion; Stiftstrasse 34-36 45470 Muelheim an der Ruhr Germany
| | - Werner Reckien
- Mulliken Center for Theoretical Chemistry; University of Bonn; Beringstr. 4+6 Bonn Germany
| | - Ivan Palazzo
- Department of Chemistry; Imperial College London; 2AZ London, SW7 UK
| | - Tom Welton
- Department of Chemistry; Imperial College London; 2AZ London, SW7 UK
| | - Oldamur Hollóczki
- Mulliken Center for Theoretical Chemistry; University of Bonn; Beringstr. 4+6 Bonn Germany
| |
Collapse
|
17
|
Firaha D, Gibalova AV, Hollóczki O. Basic Phosphonium Ionic Liquids as Wittig Reagents. ACS OMEGA 2017; 2:2901-2911. [PMID: 31457625 PMCID: PMC6641186 DOI: 10.1021/acsomega.7b00230] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Accepted: 06/08/2017] [Indexed: 06/10/2023]
Abstract
The possibility of designing a solvent/reagent for Wittig reactions from basic phosphonium salts is explored theoretically. In the suggested R4P+PhO- and Ph3PR+PhO- ionic liquids (ILs), the phenolate anion is prone to remove the α-proton from the alkyl chains, forming a phosphorous ylide. Significant hydrogen bonding between the oxygen atoms of the anions and α-hydrogen atoms of the cations were found by molecular dynamics simulations of these substances; therefore, proton transfer between the two ions is inherently supported by the structure of the liquid as well. The subsequent steps of the Wittig reaction from the phosphorous ylide were also found to be energetically possible. The mesoscopic structure of these materials exhibits a significant segregation into polar and nonpolar domains, which may also allow an easy dissolution of the substrates. The formation of a pentacoordinated phosphorous derivative through P-O bond formation was found to be also possible in the gas phase for both kind of compounds. Accordingly, having such basic anions in phosphonium-based ILs may produce such a neutral and therefore volatile species, which may hold further significant applications for these solvents in ion-exchange and separation techniques and in synthesis.
Collapse
|
18
|
Dhumal NR, Kiefer J, Turton D, Wynne K, Kim HJ. Dielectric Relaxation of the Ionic Liquid 1-Ethyl-3-methylimidazolium Ethyl Sulfate: Microwave and Far-IR Properties. J Phys Chem B 2017; 121:4845-4852. [DOI: 10.1021/acs.jpcb.7b00160] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Nilesh R. Dhumal
- Department
of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Johannes Kiefer
- Technische
Thermodynamik, Universität Bremen, 28359 Bremen, Germany
| | - David Turton
- School
of Chemistry, University of Glasgow, Glasgow G12 8QQ, U.K
| | - Klaas Wynne
- School
of Chemistry, University of Glasgow, Glasgow G12 8QQ, U.K
| | - Hyung J. Kim
- Department
of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
- School
of Computational Sciences, Korea Institute for Advanced Study, Seoul 02455, Korea
| |
Collapse
|
19
|
Gehrke S, Schmitz K, Hollóczki O. Is Carbene Formation Necessary for Dissolving Cellulose in Ionic Liquids? J Phys Chem B 2017; 121:4521-4529. [DOI: 10.1021/acs.jpcb.7b00631] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sascha Gehrke
- Mulliken
Center for Theoretical Chemistry, University of Bonn, Beringstr. 4 + 6, D-53115 Bonn, Germany
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, D-45470 Muelheim an der Ruhr, Germany
| | - Karola Schmitz
- Mulliken
Center for Theoretical Chemistry, University of Bonn, Beringstr. 4 + 6, D-53115 Bonn, Germany
| | - Oldamur Hollóczki
- Mulliken
Center for Theoretical Chemistry, University of Bonn, Beringstr. 4 + 6, D-53115 Bonn, Germany
| |
Collapse
|
20
|
Izgorodina EI, Seeger ZL, Scarborough DLA, Tan SYS. Quantum Chemical Methods for the Prediction of Energetic, Physical, and Spectroscopic Properties of Ionic Liquids. Chem Rev 2017; 117:6696-6754. [PMID: 28139908 DOI: 10.1021/acs.chemrev.6b00528] [Citation(s) in RCA: 125] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The accurate prediction of physicochemical properties of condensed systems is a longstanding goal of theoretical (quantum) chemistry. Ionic liquids comprising entirely of ions provide a unique challenge in this respect due to the diverse chemical nature of available ions and the complex interplay of intermolecular interactions among them, thus resulting in the wide variability of physicochemical properties, such as thermodynamic, transport, and spectroscopic properties. It is well understood that intermolecular forces are directly linked to physicochemical properties of condensed systems, and therefore, an understanding of this relationship would greatly aid in the design and synthesis of functionalized materials with tailored properties for an application at hand. This review aims to give an overview of how electronic structure properties obtained from quantum chemical methods such as interaction/binding energy and its fundamental components, dipole moment, polarizability, and orbital energies, can help shed light on the energetic, physical, and spectroscopic properties of semi-Coulomb systems such as ionic liquids. Particular emphasis is given to the prediction of their thermodynamic, transport, spectroscopic, and solubilizing properties.
Collapse
Affiliation(s)
- Ekaterina I Izgorodina
- Monash Computational Chemistry Group, School of Chemistry, Monash University , 17 Rainforest Walk, Clayton, Victoria 3800, Australia
| | - Zoe L Seeger
- Monash Computational Chemistry Group, School of Chemistry, Monash University , 17 Rainforest Walk, Clayton, Victoria 3800, Australia
| | - David L A Scarborough
- Monash Computational Chemistry Group, School of Chemistry, Monash University , 17 Rainforest Walk, Clayton, Victoria 3800, Australia
| | - Samuel Y S Tan
- Monash Computational Chemistry Group, School of Chemistry, Monash University , 17 Rainforest Walk, Clayton, Victoria 3800, Australia
| |
Collapse
|
21
|
Halat P, Seeger ZL, Barrera Acevedo S, Izgorodina EI. Trends in Two- and Three-Body Effects in Multiscale Clusters of Ionic Liquids. J Phys Chem B 2017; 121:577-588. [PMID: 27991797 DOI: 10.1021/acs.jpcb.6b10101] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Applications of higher correlated levels of ab initio theory to condensed systems require a significant amount of computational resources. The recent development of the fragment molecular orbital (FMO) approach alleviates this issue by splitting the system into individual fragments and achieves the accuracy of the method by accounting for all possible two-body and three-body interactions. In this work a comprehensive application of the FMO approach in combination with a second order of Møller-Plesset perturbation theory method, MP2, is presented for multiscale clusters of ionic liquids such as [C1mim]X, [C1mpyr]X, [C2py]X, and [NMe4]X, where X = chloride and tetrafluoroborates, BF4-, with the clusters varying in size from 4, 8, 16, to 32 ion pairs. Reliable cutoff criteria for the inclusion of two-body and three-body interactions are identified for both HF energy and MP2 correlation energy to achieve the desired accuracy of 1 kJ mol-1. The importance of two-body and three-body interactions in ionic liquids is also discussed.
Collapse
Affiliation(s)
- Peter Halat
- Monash Computational Chemistry Group, School of Chemistry, Monash University , 17 Rainforest Walk, Clayton, Victoria 3800, Australia
| | - Zoe L Seeger
- Monash Computational Chemistry Group, School of Chemistry, Monash University , 17 Rainforest Walk, Clayton, Victoria 3800, Australia
| | - Santiago Barrera Acevedo
- School of Mathematical Sciences, Monash University , 9 Rainforest Walk, Clayton, Victoria 3800., Australia
| | - Ekaterina I Izgorodina
- Monash Computational Chemistry Group, School of Chemistry, Monash University , 17 Rainforest Walk, Clayton, Victoria 3800, Australia
| |
Collapse
|
22
|
Weber H, Kirchner B. Complex Structural and Dynamical Interplay of Cyano-Based Ionic Liquids. J Phys Chem B 2016; 120:2471-83. [DOI: 10.1021/acs.jpcb.6b00098] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Henry Weber
- Mulliken Center for Theoretical
Chemistry, Universität Bonn, Beringstrasse 4 + 6, D-53115 Bonn, Germany
| | - Barbara Kirchner
- Mulliken Center for Theoretical
Chemistry, Universität Bonn, Beringstrasse 4 + 6, D-53115 Bonn, Germany
| |
Collapse
|
23
|
Kirchner B, Malberg F, Firaha DS, Hollóczki O. Ion pairing in ionic liquids. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2015; 27:463002. [PMID: 26509867 DOI: 10.1088/0953-8984/27/46/463002] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
In the present article we briefly review the extensive discussion in literature about the presence or absence of ion pair-like aggregates in ionic liquids. While some experimental studies point towards the presence of neutral subunits in ionic liquids, many other experiments cannot confirm or even contradict their existence. Ion pairs can be detected directly in the gas phase, but no direct method is available to observe such association behavior in the liquid, and the corresponding indirect experimental proofs are based on such assumptions as unity charges at the ions. However, we have shown by calculating ionic liquid clusters of different sizes that assuming unity charges for ILs is erroneous, because a substantial charge transfer is taking place between the ionic liquid ions that reduce their total charge. Considering these effects might establish a bridge between the contradicting experimental results on this matter. Beside these results, according to molecular dynamics simulations the lifetimes of ion-ion contacts and their joint motions are far too short to verify the existence of neutral units in these materials.
Collapse
Affiliation(s)
- Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, Institut für Physikalische und Theoretische Chemie Universität Bonn, Beringstraße 4+6, D-53115 Bonn, Germany
| | | | | | | |
Collapse
|
24
|
Katsyuba SA, Vener MV, Zvereva EE, Fei Z, Scopelliti R, Brandenburg JG, Siankevich S, Dyson PJ. Quantification of Conventional and Nonconventional Charge-Assisted Hydrogen Bonds in the Condensed and Gas Phases. J Phys Chem Lett 2015; 6:4431-4436. [PMID: 26496074 DOI: 10.1021/acs.jpclett.5b02175] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Charge-assisted hydrogen bonds (CAHBs) play critical roles in many systems from biology through to materials. In none of these areas has the role and function of CAHBs been explored satisfactorily because of the lack of data on the energy of CAHBs in the condensed phases. We have, for the first time, quantified three types of CAHBs in both the condensed and gas phases for 1-(2'-hydroxylethyl)-3-methylimidazolium acetate ([C2OHmim][OAc]). The energy of conventional OH···[OAc](-) CAHBs is ∼10 kcal·mol(-1), whereas nonconventional C(sp2)H···[OAc](-) and C(sp3)H···[OAc](-) CAHBs are weaker by ∼5-7 kcal·mol(-1). In the gas phase, the strength of the nonconventional CAHBs is doubled, whereas the conventional CAHBs are strengthened by <20%. The influence of cooperativity effects on the ability of the [OAc](-) anion to deprotonate the imidazolium cation is evaluated. The ability to quantify CAHBs in the condensed phase on the basis of easier accessible gas-phase estimates is highlighted.
Collapse
Affiliation(s)
- Sergey A Katsyuba
- A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan Scientific Centre of the Russian Academy of Sciences , Arbuzov Street 8, 420088 Kazan, Russia
| | - Mikhail V Vener
- Department of Quantum Chemistry, Mendeleev University of Chemical Technology , Miusskaya Square 9, 125047 Moscow, Russia
| | - Elena E Zvereva
- A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan Scientific Centre of the Russian Academy of Sciences , Arbuzov Street 8, 420088 Kazan, Russia
- Institut de Nanosciences et Cryogénie, SP2M/L_sim, CEA , 17 Rue des Martyrs, 38054 Grenoble, France
| | - Zhaofu Fei
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL) EPFL - BCH , CH-1015 Lausanne, Switzerland
| | - Rosario Scopelliti
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL) EPFL - BCH , CH-1015 Lausanne, Switzerland
| | - Jan Gerit Brandenburg
- Mulliken Center for Theoretical Chemistry, Institut für Physikalische und Theoretische Chemie der Universität Bonn , Beringstrasse 4, 53115 Bonn, Germany
| | - Sviatlana Siankevich
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL) EPFL - BCH , CH-1015 Lausanne, Switzerland
| | - Paul J Dyson
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL) EPFL - BCH , CH-1015 Lausanne, Switzerland
| |
Collapse
|
25
|
|
26
|
Kirchner B, Hollóczki O, Canongia Lopes JN, Pádua AAH. Multiresolution calculation of ionic liquids. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2014. [DOI: 10.1002/wcms.1212] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Barbara Kirchner
- Mulliken Center for Theoretical Chemistry; Rheinische Friedrich-Wilhelms-Universität Bonn; Bonn Germany
| | - Oldamur Hollóczki
- Mulliken Center for Theoretical Chemistry; Rheinische Friedrich-Wilhelms-Universität Bonn; Bonn Germany
| | - José Nuno Canongia Lopes
- Centro de Química Estrutural, Instituto Superior Técnico; Universidade de Lisboa; Lisboa Portugal
- Instituto de Tecnologia Química e Biológica; Universidade Nova de Lisboa; Lisboa Portugal
| | - Agílio A. H. Pádua
- Institut de Chimie de Clermont-Ferrand; Université Blaise Pascal and CNRS; Clermont-Ferrand France
| |
Collapse
|
27
|
Brunetti B, Ciccioli A, Gigli G, Lapi A, Misceo N, Tanzi L, Vecchio Ciprioti S. Vaporization of the prototypical ionic liquid BMImNTf₂ under equilibrium conditions: a multitechnique study. Phys Chem Chem Phys 2014; 16:15653-61. [PMID: 24958199 DOI: 10.1039/c4cp01673d] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The vaporization behaviour and thermodynamics of the ionic liquid 1-butyl-3-methylimidazolium bis(trifluoromethyl)sulfonylimide (BMImNTf2) were studied by combining the Knudsen Effusion Mass Loss (KEML) and Knudsen Effusion Mass Spectrometry (KEMS) techniques. KEML studies were carried out in a large temperature range (398-567) K by using effusion orifices with 0.3, 1, and 3 mm diameters. The vapor pressures so measured revealed no kinetically hindered vaporization effects and provided second-law vaporization enthalpies at the mean experimental temperatures in close agreement with literature. By exploiting the large temperature range covered, the heat capacity change associated with vaporization was estimated, resulting in a value of -66.8 J K(-1) mol(-1), much lower than that predicted from calorimetric measurements on the liquid phase and theoretical calculations on the gas phase. The conversion of the high temperature vaporization enthalpy to 298 K was discussed and the value Δ(l)(g)H(m)(298 K) = (128.6 ± 1.3) kJ mol(-1) assessed on the basis of data from literature and present work. Vapor pressure data were also processed by the third-law procedure using different estimations for the auxiliary thermal functions, and a Δ(l)(g)H(m)(298 K) consistent with the assessed value was obtained, although the overall agreement is sensitive to the accuracy of heat capacity data. KEMS measurements were carried out in the lower temperature range (393-467) K and showed that the largely prevailing ion species is BMIm(+), supporting the common view of BMImNTf2 vaporizing as individual, neutral ion pairs also under equilibrium conditions. By monitoring the mass spectrometric signal of this ion as a function of temperature, a second-law Δ(l)(g)H(m)(298 K) of 129.4 ± 7.3 kJ mol(-1) was obtained, well consistent with KEML and literature results. Finally, by combining KEML and KEMS measurements, the electron impact ionization cross section of BMIm(+) was estimated.
Collapse
Affiliation(s)
- Bruno Brunetti
- Istituto per lo Studio dei Materiali Nanostrutturati, CNR, c/o Dipartimento di Chimica, Sapienza Università di Roma, P.le A. Moro 5, I-00185, Rome, Italy
| | | | | | | | | | | | | |
Collapse
|