1
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Frömbgen T, Canongia Lopes JN, Kirchner B, Shimizu K. Unraveling the Morphology of [C nC 1Im]Cl Ionic Liquids Combining Cluster and Aggregation Analyses. J Phys Chem B 2024; 128:3937-3945. [PMID: 38621255 PMCID: PMC11056978 DOI: 10.1021/acs.jpcb.3c08317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 03/28/2024] [Accepted: 04/01/2024] [Indexed: 04/17/2024]
Abstract
A characteristic feature of ionic liquids is their nanosegregation, resulting in the formation of polar and nonpolar domains. The influence of increasing the alkyl side chain on the morphology of ionic liquids has been the subject of many studies. Typically, the polar network (charged part of the cation and anion) constitutes a continuous subphase that partially breaks to allow the formation of a nonpolar domain with the increase of the alkyl chain. As the nonpolar network expands, the number of tails per aggregate increases until the ionic liquid percolates. In this work, we demonstrate how the complementary software packages TRAVIS and AGGREGATES can be employed in conjunction to gain insights into the size and morphology of the [CnC1Im]Cl family, with n ∈ {2, 4, 6, 8, 10, 12}. The combination of the two approaches rounds off the picture of the intricate arrangement and structural features of the alkyl chains.
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Affiliation(s)
- Tom Frömbgen
- Mulliken
Center for Theoretical Chemistry, University
of Bonn, Beringstraße 4-6, D-53115 Bonn, Germany
- Max-Planck-Institut
für Chemische Energiekonversion, Stiftstrasse 34-36, D-45470 Mülheim an der Ruhr, Germany
| | - José Nuno Canongia Lopes
- Centro
de Química Estrutural, Institute of Molecular Sciences, Instituto Superior Técnico, Universidade de
Lisboa, Av Rovisco Pais 1, 1049 001 Lisboa, Portugal
| | - Barbara Kirchner
- Mulliken
Center for Theoretical Chemistry, University
of Bonn, Beringstraße 4-6, D-53115 Bonn, Germany
| | - Karina Shimizu
- Centro
de Química Estrutural, Institute of Molecular Sciences, Instituto Superior Técnico, Universidade de
Lisboa, Av Rovisco Pais 1, 1049 001 Lisboa, Portugal
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2
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Dick L, Buchmüller K, Kirchner B. Coordination Behavior of a Confined Ionic Liquid in Carbon Nanotubes from Molecular Dynamics Simulations. J Phys Chem B 2024. [PMID: 38660932 DOI: 10.1021/acs.jpcb.3c08493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
To understand the behavior of ionic liquids (ILs) at carbon material, i.e., carbon nanotube (CNT)-containing pores, we simulated different systems and analyzed their structural─in particular their coordination─behavior as well as their velocity distribution. The extension of our analysis tool CONAN presented here allowed us to study the coordination behavior as a function of the distance to the carbon material. Our systems were composed of three different CNTs combined with either the neat IL 1-ethyl-3-methylimidazolium tetrafluoroborate or with their NaBF4 salt mixtures. We investigated the impact of the force field charge scaling. As previously detected, the neat IL assumed radial layers within the confinement, with the radial density distribution depending strongly on the pore size. For the salt mixtures, the sodium cation remained in the bulk and was observed only once inside a tube. In all systems, the ions showed an overall decreased coordination behavior for regions in the bulk phase close to the carbon pore and within the confinement. The coordination number was always reduced with scaled charges. For charge scaling, higher dynamics was observed also in confinement. Interestingly, the average velocity of the atoms near the surface inside the confined space was higher than that in the center of the pore.
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Affiliation(s)
- Leonard Dick
- Mulliken Center for Theoretical Chemistry, Rheinische Friedrich-Wilhelms-Universität Bonn, Beringstr. 4 + 6, D-53115 Bonn, Germany
| | - Kai Buchmüller
- Mulliken Center for Theoretical Chemistry, Rheinische Friedrich-Wilhelms-Universität Bonn, Beringstr. 4 + 6, D-53115 Bonn, Germany
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, Rheinische Friedrich-Wilhelms-Universität Bonn, Beringstr. 4 + 6, D-53115 Bonn, Germany
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3
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Frömbgen T, Drysch K, Zaby P, Dölz J, Ingenmey J, Kirchner B. Quantum Cluster Equilibrium Theory for Multicomponent Liquids. J Chem Theory Comput 2024; 20:1838-1846. [PMID: 38372002 DOI: 10.1021/acs.jctc.3c00799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
In this work, we present a new theory to treat multicomponent liquids based on quantum-chemically calculated clusters. The starting point is the binary quantum cluster equilibrium theory, which is able to treat binary systems. The theory provides one equation with two unknowns. In order to obtain another linearly independent equation, the conservation of mass is used. However, increasing the number of components leads to more unknowns, and this requires linearly independent equations. We address this challenge by introducing a generalization of the conservation of arbitrary quantities accompanied by a comprehensive mathematical proof. Furthermore, a case study for the application of the new theory to ternary mixtures of chloroform, methanol, and water is presented. Calculated enthalpies of vaporization for the whole composition range are given, and the populations or weights of the different clusters are visualized.
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Affiliation(s)
- Tom Frömbgen
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstraße 4 + 6, Bonn D-53115, Germany
- Max-Planck-Institut Für Chemische Energiekonversion, Stiftstrasse 34-36, Mülheim an der Ruhr D-45470, Germany
| | - Katrin Drysch
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstraße 4 + 6, Bonn D-53115, Germany
| | - Paul Zaby
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstraße 4 + 6, Bonn D-53115, Germany
| | - Jürgen Dölz
- Institute for Numerical Simulation, University of Bonn, Friedrich-Hirzebruch-Allee 7, Bonn D-53115, Germany
| | - Johannes Ingenmey
- CNRS, Physico-Chimie des Électrolytes et Nanosystèmes Interfaciaux, Sorbonne Université, Paris F-75005, France
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstraße 4 + 6, Bonn D-53115, Germany
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4
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Shea JE, Crawford TD, Kirchner B, Hartland GV, Aumiller W. 50 and 100 Years Ago in The Journal of Physical Chemistry─2024 Edition. J Phys Chem A 2024; 128:1551-1554. [PMID: 38449433 DOI: 10.1021/acs.jpca.4c00715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2024]
Affiliation(s)
- Joan-Emma Shea
- Department of Chemistry and Biochemistry and Department of Physics, University of California, Santa Barbara, Santa Barbara, California 93106, United States
| | - T Daniel Crawford
- Department of Chemistry, Virginia Tech, Blacksburg, Virginia 24061, United States
- Molecular Sciences Software Institute, Blacksburg, Virginia 24060, United States
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, Clausius Institute of Physical and Theoretical Chemistry, University of Bonn, D-53115 Bonn, Germany
| | - Gregory V Hartland
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - William Aumiller
- American Chemical Society, 1155 Sixteenth Street N.W., Washington, DC 20036, United States
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5
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Shea JE, Crawford TD, Kirchner B, Hartland GV, Aumiller W. 50 and 100 Years Ago in The Journal of Physical Chemistry─2024 Edition. J Phys Chem B 2024; 128:2053-2056. [PMID: 38449439 DOI: 10.1021/acs.jpcb.4c00716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2024]
Affiliation(s)
- Joan-Emma Shea
- Department of Chemistry and Biochemistry and Department of Physics, University of California, Santa Barbara, Santa Barbara, California 93106, United States
| | - T Daniel Crawford
- Department of Chemistry, Virginia Tech, Blacksburg, Virginia 24061, United States
- Molecular Sciences Software Institute, Blacksburg, Virginia 24060, United States
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, Clausius Institute of Physical and Theoretical Chemistry, University of Bonn, D-53115 Bonn, Germany
| | - Gregory V Hartland
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - William Aumiller
- American Chemical Society, 1155 Sixteenth Street N.W., Washington, DC 20036, United States
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6
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Taherivardanjani S, Wylie L, Dötzer R, Kirchner B. Exploring the Influence of the Phosphorus-Heteroatom Substitution in Nicotine on Its Electronic and Vibrational Spectroscopic Properties. Chemistry 2024; 30:e202302534. [PMID: 37984418 DOI: 10.1002/chem.202302534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 11/10/2023] [Accepted: 11/13/2023] [Indexed: 11/22/2023]
Abstract
The influence of phosphorus substitution of nitrogen in heterocyclic compounds on the vibrational spectroscopy as well as frontier molecular orbitals are analyzed. Nicotine with two nitrogen atoms in its structure is taken as the sample system to be studied computationally. By replacing the nitrogen atom in one or both rings of this molecule with phosphorus, three nicotine derivatives are created. The vibrational circular dichroism and infrared spectra of these four molecules in their monomer state, as well as the assemblies up to trimers are determined. The aforementioned spectra are calculated using static quantum chemical calculations employing a cluster-weighted approach. The calculated gas phase spectra of nicotine are compared to their respective experimental spectra. It is observed that the nicotine derivatives with phosphorus in the methylpyrrolidine ring have considerably different gas phase and bulk phase vibrational circular dichroism spectra when compared to nicotine. The phosphorus substitution reduces the energy gap between the highest occupied molecular orbital and the lowest unoccupied molecular orbital as well as altering the polarizability and reactivity of the investigated molecules.
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Affiliation(s)
- Shima Taherivardanjani
- Mulliken Center for Theoretical Chemistry, Institute for Physical and Theoretical Chemistry, Beringstr. 4, D-53115, Bonn, Germany
| | - Luke Wylie
- Mulliken Center for Theoretical Chemistry, Institute for Physical and Theoretical Chemistry, Beringstr. 4, D-53115, Bonn, Germany
| | | | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, Institute for Physical and Theoretical Chemistry, Beringstr. 4, D-53115, Bonn, Germany
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7
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Shea JE, Crawford TD, Kirchner B, Hartland GV, Aumiller W. 2023: A Year in Review. J Phys Chem B 2024; 128:1-2. [PMID: 38204406 DOI: 10.1021/acs.jpcb.3c07869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2024]
Affiliation(s)
- Joan-Emma Shea
- Department of Chemistry and Biochemistry and Department of Physics, University of California, Santa Barbara, California 93106, United States
| | - T Daniel Crawford
- Department of Chemistry, Virginia Tech, Blacksburg, Virginia 24061, United States
- Molecular Sciences Software Institute, Blacksburg, Virginia 24060, United States
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, Clausius Institute of Physical and Theoretical Chemistry, University of Bonn, D-53115 Bonn, Germany
| | - Gregory V Hartland
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - William Aumiller
- American Chemical Society, 1155 Sixteenth Street N.W., Washington, D.C. 20036, United States
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8
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Shea JE, Crawford TD, Kirchner B, Hartland GV, Aumiller W. 2023: A Year in Review. J Phys Chem A 2024; 128:1-2. [PMID: 38204409 DOI: 10.1021/acs.jpca.3c07868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2024]
Affiliation(s)
- Joan-Emma Shea
- Department of Chemistry and Biochemistry and Department of Physics, University of California, Santa Barbara, California 93106, United States
| | - T Daniel Crawford
- Department of Chemistry, Virginia Tech, Blacksburg, Virginia 24061, United States
- Molecular Sciences Software Institute, Blacksburg, Virginia 24060, United States
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, Clausius Institute of Physical and Theoretical Chemistry, University of Bonn, D-53115 Bonn, Germany
| | - Gregory V Hartland
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - William Aumiller
- American Chemical Society, 1155 Sixteenth Street N.W., Washington, D.C. 20036, United States
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9
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Blasius J, Drysch K, Pilz FH, Frömbgen T, Kielb P, Kirchner B. Efficient Prediction of Mole Fraction Related Vibrational Frequency Shifts. J Phys Chem Lett 2023; 14:10531-10536. [PMID: 37972218 DOI: 10.1021/acs.jpclett.3c02761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2023]
Abstract
While so far it has been possible to calculate vibrational spectra of mixtures at a particular composition, we present here a novel cluster approach for a fast and robust calculation of mole fraction dependent infrared and vibrational circular dichroism spectra at the example of acetonitrile/(R)-butan-2-ol mixtures. By assigning weights to a limited number of quantum chemically calculated clusters, vibrational spectra can be obtained at any desired composition by a weighted average of the single cluster spectra. In this way, peak positions carrying information about intermolecular interactions can be predicted. We show that mole fraction dependent peak shifts can be accurately modeled and, that experimentally recorded infrared spectra can be reproduced with high accuracy over the entire mixing range. Because only a very limited number of clusters is required, the presented approach is a valuable and computationally efficient tool to access mole fraction dependent spectra of mixtures on a routine basis.
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Affiliation(s)
- Jan Blasius
- Mulliken Center for Theoretical Chemistry, Clausius Institute of Physical and Theoretical Chemistry, University of Bonn, Beringstraße 4-6, D-53115 Bonn, Germany
| | - Katrin Drysch
- Mulliken Center for Theoretical Chemistry, Clausius Institute of Physical and Theoretical Chemistry, University of Bonn, Beringstraße 4-6, D-53115 Bonn, Germany
| | - Frank Hendrik Pilz
- Clausius Institute of Physical and Theoretical Chemistry, University of Bonn, Wegelerstraße 12, D-53115 Bonn, Germany
| | - Tom Frömbgen
- Mulliken Center for Theoretical Chemistry, Clausius Institute of Physical and Theoretical Chemistry, University of Bonn, Beringstraße 4-6, D-53115 Bonn, Germany
- Max-Planck-Institut für Chemische Energiekonversion, Stiftstrasse 34-36, D-45470 Mülheim an der Ruhr, Germany
| | - Patrycja Kielb
- Clausius Institute of Physical and Theoretical Chemistry, University of Bonn, Wegelerstraße 12, D-53115 Bonn, Germany
- Transdisciplinary Research Area "Building Blocks of Matter and Fundamental Interactions" (TRA Matter), University of Bonn, D-53115 Bonn, Germany
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, Clausius Institute of Physical and Theoretical Chemistry, University of Bonn, Beringstraße 4-6, D-53115 Bonn, Germany
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10
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Dick L, Kirchner B. CONAN─Novel Tool to Create and Analyze Liquids in Confined Space. J Chem Inf Model 2023; 63:6706-6716. [PMID: 37907068 PMCID: PMC10649805 DOI: 10.1021/acs.jcim.3c01075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Indexed: 11/02/2023]
Abstract
Modeling of complex liquids at solid surfaces and in confinement is gaining attention due to an increase in computer power and advancement of simulation techniques. Therefore, tools to set up structures and for analysis are needed. In this paper, we present CONAN─a Python code designed to facilitate the study of liquids interacting with solid structures, such as walls or pores. Among other things, the program provides the option to generate a variety of different structures, including carbon walls and nanotubes and their boron nitride analogs, as well as the ability to analyze various structural properties of confined and interfacial liquids. In the case of the ionic liquid 1-butyl-3-methylimidazolium acetate in carbon nanotubes of different sizes, we demonstrate the abilities of our tool. The average density within the confinement highly depends on the carbon nanotube size, and it is generally lower than the density of the bulk liquid. The arrangement of the individual species within the tube also depends on size, with radial layers forming within the tubular confinement. The density is largely increased in the respective layers, while it is drastically reduced between the layers.
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Affiliation(s)
- Leonard Dick
- Mulliken Center for Theoretical Chemistry, Rheinische Friedrich-Wilhelms-Universität Bonn, Beringstr. 4+6, D-53115 Bonn, Germany
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, Rheinische Friedrich-Wilhelms-Universität Bonn, Beringstr. 4+6, D-53115 Bonn, Germany
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11
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Wylie L, Kéri M, Udvardy A, Hollóczki O, Kirchner B. On the Rich Chemistry of Pseudo-Protic Ionic Liquid Electrolytes. ChemSusChem 2023; 16:e202300535. [PMID: 37364035 DOI: 10.1002/cssc.202300535] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2023] [Revised: 06/25/2023] [Accepted: 06/26/2023] [Indexed: 06/28/2023]
Abstract
Mixing weak acids and bases can produce highly complicated binary mixtures, called pseudo-protic ionic liquids, in which a complex network of effects determines the physicochemical properties that are currently impossible to predict. In this joint computational-experimental study, we investigated 1-methylimidazole-acetic acid mixtures through the whole concentration range. Effects of the varying ionization and excess of either components on the properties, such as density, diffusion coefficients, and overall hydrogen bonding structure were uncovered. A special emphasis was put on understanding the multiple factors that govern the conductivity of the system. In the presence of an excess of acetic acid, the 1-methylimidazolium acetate ion pairs dissociate more efficiently, resulting in a higher concentration of independently moving, conducting ions. However, the conductivity measurements showed that higher concentrations of acetic acid improve the conductivity beyond this effect, suggesting in addition to standard dilution effects the occurrence of Grotthuss diffusion in high acid-to-base ratios. The results here will potentially help designing novel electrolytes and proton conducting systems, which can be exploited in a variety of applications.
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Affiliation(s)
- Luke Wylie
- University of Bonn, Clausius Institute of Physical and Theoretical Chemistry, Mulliken Center for Theoretical Chemistry, Beringstr. 4, 53115, Bonn, Germany
| | - Mónika Kéri
- University of Debrecen, Department of Physical Chemistry, Egyetem tér 1, 4032, Debrecen, Hungary
| | - Antal Udvardy
- University of Debrecen, Department of Physical Chemistry, Egyetem tér 1, 4032, Debrecen, Hungary
| | - Oldamur Hollóczki
- University of Debrecen, Department of Physical Chemistry, Egyetem tér 1, 4032, Debrecen, Hungary
| | - Barbara Kirchner
- University of Bonn, Clausius Institute of Physical and Theoretical Chemistry, Mulliken Center for Theoretical Chemistry, Beringstr. 4, 53115, Bonn, Germany
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12
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Ramazanova K, Müller AK, Lönnecke P, Hollóczki O, Kirchner B, Hey-Hawkins E. Ring-Opening Reaction of 1-Phospha-2-Azanorbornenes via P-N Bond Cleavage and Reversibility Studies. Molecules 2023; 28:7163. [PMID: 37894642 PMCID: PMC10609391 DOI: 10.3390/molecules28207163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 10/10/2023] [Accepted: 10/16/2023] [Indexed: 10/29/2023] Open
Abstract
The reactive P-N bond in 1-phospha-2-azanorbornenes is readily cleaved by simple alcohols to afford P-chiral 2,3-dihydrophosphole derivatives as a racemic mixture. The isolation of the products was not possible due to the reversibility of the reaction, which could, however, be stopped by sulfurization of the phosphorus atom, thus efficiently blocking the lone pair of electrons, as exemplified for 6b yielding structurally characterized 8b. Additionally, the influence of the substituent in the α position to the phosphorus atom (H, Ph, 2-py, CN) on the reversibility of the reaction was studied. Extensive theoretical calculations for understanding the ring-closing mechanism suggested that a multi-step reaction with one or more intermediates was most probable.
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Affiliation(s)
- Kyzgaldak Ramazanova
- Institute of Inorganic Chemistry, Faculty of Chemistry and Mineralogy, Leipzig University, Johannisallee 29, 04103 Leipzig, Germany; (K.R.); (P.L.)
| | - Anna Karina Müller
- Mulliken Center for Theoretical Chemistry, Institute for Physical and Theoretical Chemistry, Beringstr. 4, 53115 Bonn, Germany; (A.K.M.); (B.K.)
| | - Peter Lönnecke
- Institute of Inorganic Chemistry, Faculty of Chemistry and Mineralogy, Leipzig University, Johannisallee 29, 04103 Leipzig, Germany; (K.R.); (P.L.)
| | - Oldamur Hollóczki
- Department of Physical Chemistry, Faculty of Science and Technology, University of Debrecen, Egyetem ter 1, H-4010 Debrecen, Hungary;
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, Institute for Physical and Theoretical Chemistry, Beringstr. 4, 53115 Bonn, Germany; (A.K.M.); (B.K.)
| | - Evamarie Hey-Hawkins
- Institute of Inorganic Chemistry, Faculty of Chemistry and Mineralogy, Leipzig University, Johannisallee 29, 04103 Leipzig, Germany; (K.R.); (P.L.)
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13
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Wylie L, Barham JP, Kirchner B. Solvent Dependency of Catalyst-Substrate Aggregation Through π-π Stacking in Photoredox Catalysis. Chemphyschem 2023; 24:e202300470. [PMID: 37477880 DOI: 10.1002/cphc.202300470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 07/21/2023] [Accepted: 07/21/2023] [Indexed: 07/22/2023]
Abstract
Assemblies of photoredox catalysts and their target substrates prior to photoexcitation is a phenomenon naïvely overlooked by the majority of synthetic chemists, but can have profound influences on reactivity and selectivity in photocatalytic reactions. In this study, we determine the aggregation states of triarylamine radical cationic photocatalysts with various target arene substrates in different solvents by specifically parameterized polarizable molecular dynamics simulations. A π-stacking interaction previously implicated by more expensive, less-representative quantum calculations is confirmed. Critically, this study presents new insights on: i) the ability of solvents (MeCN vs DMF) to make or break a photocatalytic reaction by promoting (MeCN) or demoting (DMF) its catalyst-substrate assemblies, which is a determining factor for reactivity, ii) the average "lifetimes" of assemblies in solution from a dynamic simulation. We find that both in the ground state and the photoexcited state, the cationic radical assemblies remain intact for periods often higher than 60 ps, rendering them ideally suitable to undergo intra-assembly electron transfer reactions upon photoexcitation. Such aspects have not addressed by previous studies on synthetic photocatalytic reactions involving non-covalent assemblies.
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Affiliation(s)
- Luke Wylie
- University of Bonn, Clausius Institute of Physical and Theoretical Chemistry, Mulliken Center for Theoretical Chemistry, Beringstr. 4, D-53115, Bonn, Germany
| | - Joshua P Barham
- Institute of Organic Chemistry, University of Regensburg, Universitätsstraße 31, D93053, Regensburg, Germany
| | - Barbara Kirchner
- University of Bonn, Clausius Institute of Physical and Theoretical Chemistry, Mulliken Center for Theoretical Chemistry, Beringstr. 4, D-53115, Bonn, Germany
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14
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Dong W, Alizadeh V, Blasius J, Wylie L, Dick L, Fan Z, Kirchner B. Locality in amino-acid based imidazolium ionic liquids. Phys Chem Chem Phys 2023; 25:24678-24685. [PMID: 37667665 DOI: 10.1039/d3cp02671j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/06/2023]
Abstract
Several amino-acid based imidazolium ILs are investigated through the use of ab initio molecular dynamics (AIMD), which includes full polarization. The electric dipole moment distribution and polarization is used as a means of characterizing and understanding these complex systems. Various charge scheme methods were analyzed (Wannier function, Blöchl, Löwdin and Mulliken charge schemes and Voronoi tessellation) to determine their ability to predict dipole moments. These results and the following comparison of methods further deepen the knowledge of polarization by highlighting the importance of the anion and cation separately on polarizability contribution and the need to select a suitable method to predict these. The angular probability distribution is utilized to measure the degree of locality in monopole-dipole electrostatic interactions, which showed no preferential alignment over 700 pm. In addition, the IR and Raman spectra from Voronoi tessellation of [C2C1Im][ala] were analyzed. In these, the strongest signalling peaks showed consistency with experiment and the ability to differentiate between anion and cation components of the IL.
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Affiliation(s)
- Wenbo Dong
- 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.
| | - Jan Blasius
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstraße 4+6, D-53115 Bonn, Germany.
| | - Luke Wylie
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstraße 4+6, D-53115 Bonn, Germany.
| | - Leonard Dick
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstraße 4+6, D-53115 Bonn, Germany.
| | - Zhijie Fan
- Department of Chemistry, Imperial College London, South Kensington Campus, London SW7 2AZ, UK
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstraße 4+6, D-53115 Bonn, Germany.
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15
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Blasius J, Kirchner B. Selective Chirality Transfer to the Bis(trifluoromethylsulfonyl)imide Anion of an Ionic Liquid. Chemistry 2023; 29:e202301239. [PMID: 37341169 DOI: 10.1002/chem.202301239] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 06/19/2023] [Accepted: 06/21/2023] [Indexed: 06/22/2023]
Abstract
Chirality transfer from the chiral molecule (R)-1,2-propylene oxide to the achiral anion of the 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ionic liquid is observed. The chiral probe selectively affects one part of the binary ionic liquid, i. e., it has previously been shown experimentally and theoretically that this particular imidazolium cation can be affected by chirality transfer, but in the present system chirality is almost exclusively transferred to the anion and not to both parts of the solvent (anion and cation). This observation is of high relevance because of its selectivity and because anion effects are usually much more important in ionic liquid research than cation effects. From ab initio molecular dynamics simulations, a conformational analysis and dissected vibrational circular dichroism spectra are obtained to study the chirality transfer. While in the neat ionic liquid two mirror imaged trans conformers of the anion occur almost equally, we observe an excess of one of these conformers in the presence of the chiral solute, causing optical activity of the anion. Although the cis conformers are not tremendously affected by the chirality transfer, they gain in total population when (R)-1,2-propylene oxide is dissolved in the ionic liquid.
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Affiliation(s)
- Jan Blasius
- Mulliken Center for Theoretical Chemistry, Clausius-Institute for Physical and Theoretical Chemistry, University of Bonn, Beringstraße 4-6, D-53115, Bonn, Germany
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, Clausius-Institute for Physical and Theoretical Chemistry, University of Bonn, Beringstraße 4-6, D-53115, Bonn, Germany
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16
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Fickenscher ZBG, Lönnecke P, Müller AK, Baumann W, Kirchner B, Hey-Hawkins E. Stronger Together! Mechanistic Investigation into Synergistic Effects during Homogeneous Carbon Dioxide Hydrogenation Using a Heterobimetallic Catalyst. Inorg Chem 2023; 62:12750-12761. [PMID: 37506709 DOI: 10.1021/acs.inorgchem.3c01303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/30/2023]
Abstract
A series of group 6 heterobimetallic complexes [M0;IrIII] (M = Cr, Mo, W) were synthesized and fully characterized, and the catalytic behavior was studied. The heterobimetallic complex [Mo0;IrIII] (C1) was by far the most active and has shown a considerable synergistic effect, with both metals actively participating in homogeneous carbon dioxide hydrogenation, leading to formate salts. Based on theoretical calculations, the synergistic interaction is due to Pauli repulsion, lowering the transition state and thus enabling higher catalytic activity. The mechanism of both the hydrogenation itself and the synergistic interaction was studied by NMR spectroscopy, kinetic measurements, and theoretical calculations. The homogeneous nature of the reaction was proven using in situ high-pressure (HP) NMR experiments. The same experiments also showed that the octahedral Mo(CO)3P3 moiety of the complex is stable under the reaction conditions. The hydride complex is the resting state because the hydride transfer is the rate-determining step. This is supported by kinetic measurements, in situ HP NMR experiments, and theoretical calculations and is in contrast to the monometallic IrIII counterpart of C1.
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Affiliation(s)
- Zeno B G Fickenscher
- Institute of Inorganic Chemistry, Universität Leipzig, Johannisallee 29, D-04103 Leipzig, Germany
| | - Peter Lönnecke
- Institute of Inorganic Chemistry, Universität Leipzig, Johannisallee 29, D-04103 Leipzig, Germany
| | - Anna K Müller
- Mulliken Center for Theoretical Chemistry, Institute for Physical and Theoretical Chemistry, Beringstraße 4, 53115 Bonn, Germany
| | - Wolfgang Baumann
- Leibniz-Institut für Katalyse eV, Albert-Einstein-Straße 29a, 18059 Rostock, Germany
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, Institute for Physical and Theoretical Chemistry, Beringstraße 4, 53115 Bonn, Germany
| | - Evamarie Hey-Hawkins
- Institute of Inorganic Chemistry, Universität Leipzig, Johannisallee 29, D-04103 Leipzig, Germany
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17
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Barboiu M, Kirchner B, Perlt E, Scarso A. H 2 Open - Guest Editorial. ChemistryOpen 2023:e202300072. [PMID: 37279370 DOI: 10.1002/open.202300072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023] Open
Abstract
This special collection presents original research articles and reviews that are connected to the multifaceted and rich chemistry of water. These works serve as an illustration of how, despite its apparent simplicity and ubiquity, water continues to be at the center of scientific exploration from a wide range of perspectives and employing the toolbox of modern-day chemistry.
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Affiliation(s)
- Mihail Barboiu
- Institut Européen Membranes, Adaptive Supramolecular Nanosystems Group, Université de Montpellier, ENSCM, CNRS, Pl Eugene Bataillon, CC47, Montpellier 5, France
| | - Barbara Kirchner
- Universität Bonn, Mulliken Center for Theoretical Chemistry, B6 1.007, Beringstr. 4+6, 53115, Bonn, Germany
| | - Eva Perlt
- Friedrich-Schiller-Universität Jena, Otto Schott Institute of Materials Research, Löbdergraben 32, 07743, Jena, Germany
| | - Alessandro Scarso
- Università Ca' Foscari Venezia, Dipartimento di Scienze Molecolari e Nanosistemi, via Torino 155, 30172, Mestre Venezia, Italy
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18
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Fickenscher ZBG, Lönnecke P, Müller AK, Hollóczki O, Kirchner B, Hey-Hawkins E. Synergistic Catalysis in Heterobimetallic Complexes for Homogeneous Carbon Dioxide Hydrogenation. Molecules 2023; 28:molecules28062574. [PMID: 36985546 PMCID: PMC10059594 DOI: 10.3390/molecules28062574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 03/03/2023] [Accepted: 03/08/2023] [Indexed: 03/15/2023] Open
Abstract
Two heterobimetallic Mo,M’ complexes (M’ = IrIII, RhIII) were synthesized and fully characterized. Their catalytic activity in homogeneous carbon dioxide hydrogenation to formate was studied. A pronounced synergistic effect between the two metals was found, most notably between Mo and Ir, leading to a fourfold increase in activity compared with a binary mixture of the two monometallic counterparts. This synergism can be attributed to spatial proximity of the two metals rather than electronic interactions. To further understand the nature of this interaction, the mechanism of the CO2 hydrogenation to formate by a monometallic IrIII catalyst was studied using computational and spectroscopic methods. The resting state of the reaction was found to be the metal-base adduct, whereas the rate-determining step is the inner-sphere hydride transfer to CO2. Based on these findings, the synergism in the heterobimetallic complex is beneficial in this key step, most likely by further activating the CO2.
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Affiliation(s)
- Zeno B. G. Fickenscher
- Institute of Inorganic Chemistry, Universität Leipzig, Johannisallee 29, 04103 Leipzig, Germany
| | - Peter Lönnecke
- Institute of Inorganic Chemistry, Universität Leipzig, Johannisallee 29, 04103 Leipzig, Germany
| | - Anna K. Müller
- Mulliken Center for Theoretical Chemistry, Institute for Physical and Theoretical Chemistry, Beringstr. 4, 53115 Bonn, Germany
| | - Oldamur Hollóczki
- Department of Physical Chemistry, Faculty of Science and Technology, University of Debrecen, Egyetem ter 1, H-4010 Debrecen, Hungary
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, Institute for Physical and Theoretical Chemistry, Beringstr. 4, 53115 Bonn, Germany
| | - Evamarie Hey-Hawkins
- Institute of Inorganic Chemistry, Universität Leipzig, Johannisallee 29, 04103 Leipzig, Germany
- Correspondence:
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19
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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] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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20
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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.
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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
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21
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Taherivardanjani S, Blasius J, Brehm M, Dötzer R, Kirchner B. Conformer Weighting and Differently Sized Cluster Weighting for Nicotine and Its Phosphorus Derivatives. J Phys Chem A 2022; 126:7070-7083. [PMID: 36170053 DOI: 10.1021/acs.jpca.2c03133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Weighting methods applied to systems with many conformers have been broadly employed to calculate thermodynamic properties, structural characteristics, and populations. To better understand and test the sensitivity of conventional weighting methods, the conformational distributions of nicotine and its phosphorus-substituted derivatives are investigated. The weighting schemes used for this are all based on Boltzmann statistics. Classical Boltzmann factors based on the electronic energy and the Gibbs free energy are calculated at different quantum chemical levels of theory and compared to cluster weights obtained by the quantum cluster equilibrium method. Furthermore, the influence of the modified rigid-rotor-harmonic-oscillator (mRRHO) approximation on the cluster weights is investigated. The substitution of the nitrogen atom in the methylpyrrolidine ring by a phosphorus atom results in more monomer conformers and clusters being populated. The conformational distribution of the monomers remained stable at different levels of theory and weighting methods. However, going to dimers and trimers, we observe a significant influence of the level of theory, weighting method, and mRRHO cutoff on the populations of these clusters. We show that mRRHO cutoff values of 50 and 100 cm-1 yield similar results, which is why 50 cm-1 is recommended as a robust choice. Furthermore, we observe that the global minimum for ΔE0 and ΔG varies in a few cases and that the global minimum is not always the dominantly occupied structure.
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Affiliation(s)
- Shima Taherivardanjani
- Mulliken Center for Theoretical Chemistry, Clausius Institute of Physical and Theoretical Chemistry, University of Bonn, Beringstr. 4 + 6, D-53115 Bonn, Germany
| | - Jan Blasius
- Mulliken Center for Theoretical Chemistry, Clausius Institute of Physical and Theoretical Chemistry, University of Bonn, Beringstr. 4 + 6, D-53115 Bonn, Germany
| | - Martin Brehm
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, D-06120 Halle (Saale), Germany
| | - Reinhard Dötzer
- Competence Center Analytics, BASF SE, D-67056 Ludwigshafen, Germany
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, Clausius Institute of Physical and Theoretical Chemistry, University of Bonn, Beringstr. 4 + 6, D-53115 Bonn, Germany
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22
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Blasius J, Zaby P, Dölz J, Kirchner B. Uncertainty quantification of phase transition quantities from cluster weighting calculations. J Chem Phys 2022; 157:014505. [DOI: 10.1063/5.0093057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
In this work, we investigate how uncertainties in experimental input data influence the results of quantum cluster equilibrium calculations. In particular, we focus on the calculation of vaporization enthalpies and entropies of seven organic liquids, compare two computational approaches for their calculation and investigate how these properties are affected by changes in the experimental input data. It is observed that the vaporization enthalpies and entropies show a smooth dependence on changes in the reference density and boiling point. The reference density is found to have only a small influence on the vaporization thermodynamics, whereas the boiling point has a large influence on the vaporization enthalpy but only a small influence on the vaporization entropy. Furthermore we employed the Gauss--Hermite estimator in order to quantify the uncertainty in the thermodynamic functions that stems from inaccuracies in the experimental reference data at the example of the vaporization enthalpy of (\textit{R})-butan-2-ol. We quantify the uncertainty as 30.95~$\cdot$10$^{-3}$~kJ~mol$^{-1}$. Additionally we compare the convergence behaviour and computational effort of the Gauss--Hermite estimator with the Monte Carlo approach and show the superiority of the former. By this, we present how uncertainty quantification can be applied to examples from theoretical chemistry.
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Affiliation(s)
- Jan Blasius
- University of Bonn Institute of Physical and Theoretical Chemistry, Germany
| | - Paul Zaby
- University of Bonn Institute of Physical and Theoretical Chemistry, Germany
| | - Jürgen Dölz
- Institute for Numerical Simulation, University of Bonn, Friedrich-Hirzebruch-Allee 7 53115 Bonn, Germany, Germany
| | - Barbara Kirchner
- Theoretical and Physical Chemistry, University of Bonn Institute of Physical and Theoretical Chemistry, Germany
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23
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Sieland M, Schenker M, Esser L, Kirchner B, Smarsly BM. Ionic Liquid-Based Low-Temperature Synthesis of Crystalline Ti(OH)OF·0.66H 2O: Elucidating the Molecular Reaction Steps by NMR Spectroscopy and Theoretical Studies. ACS Omega 2022; 7:5350-5365. [PMID: 35187350 PMCID: PMC8851441 DOI: 10.1021/acsomega.1c06534] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 01/10/2022] [Indexed: 06/14/2023]
Abstract
We present an in-depth mechanistic study of the first steps of the solution-based synthesis of the peculiar hexagonal tungsten bronze-type Ti(OH)OF·0.66H2O solid, using NMR analyses (1H, 13C, 19F, and 11B) as well as modeling based on density functional theory (DFT) and ab initio molecular dynamics (AIMD) simulation. The reaction uses an imidazolium-based ionic liquid (IL, e.g., C x mim BF4) as a solvent and reaction partner. It is puzzling, as the fluorine-rich crystalline solid is obtained in a "beaker chemistry" procedure, starting from simple compounds forming a stable solution (BF4 --containing IL, TiCl4, H2O) at room temperature, and a remarkably low reaction temperature (95 °C) is sufficient. Building on NMR experiments and modeling, we are able to provide a consistent explanation of the peculiar features of the synthesis: evidently, the hydrolysis of the IL anion BF4 - is a crucial step since the latter provides fluoride anions, which are incorporated into the crystal structure. Contrary to expectations, BF4 - does not hydrolyze in water at room temperature but interacts with TiCl4, possibly forming a TiCl4 complex with one or two coordinated BF4 - units. This interaction also prevents the heavy hydrolysis reaction of TiCl4 with H2O but-on the other side-spurs the hydrolysis of BF4 - already at room temperature, releasing fluoride and building F-containing Ti(OH) x Cl4-x F y complexes. The possible complexes formed were analyzed using DFT calculations with suitable functionals and basis sets. We show in addition that these complexes are also formed using other titanium precursors. As a further major finding, the heating step (95 °C) is only needed for the condensation of the Ti(OH) x Cl4-x F y complexes to form the desired solid product but not for the hydrolysis of BF4 -. Our study provides ample justification to state a "special IL effect", as the liquid state, together with a stable solution, the ionic nature, and the resulting deactivation of H2O are key requirements for this synthesis.
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Affiliation(s)
- Melanie Sieland
- Institute
of Physical Chemistry, Justus Liebig University, Heinrich-Buff-Ring 17, D-35392 Giessen, Germany
| | - Manuel Schenker
- Institute
of Physical Chemistry, Justus Liebig University, Heinrich-Buff-Ring 17, D-35392 Giessen, Germany
| | - Lars Esser
- Mulliken
Center for Theoretical Chemistry, Institut für Physikalische
und Theoretische Chemie, Rheinische Friedrich-Wilhelms-Universität
Bonn, Beringstrasse 4+6, D-53115 Bonn, Germany
| | - Barbara Kirchner
- Mulliken
Center for Theoretical Chemistry, Institut für Physikalische
und Theoretische Chemie, Rheinische Friedrich-Wilhelms-Universität
Bonn, Beringstrasse 4+6, D-53115 Bonn, Germany
| | - Bernd M. Smarsly
- Institute
of Physical Chemistry, Justus Liebig University, Heinrich-Buff-Ring 17, D-35392 Giessen, Germany
- Center
of Materials Research, Justus Liebig University, Heinrich-Buff-Ring 16, D-35392 Giessen, Germany
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24
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Kirchner B, Ingenmey J, von Domaros M, Perlt E. The Ionic Product of Water in the Eye of the Quantum Cluster Equilibrium. Molecules 2022; 27:molecules27041286. [PMID: 35209075 PMCID: PMC8877775 DOI: 10.3390/molecules27041286] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 02/06/2022] [Accepted: 02/09/2022] [Indexed: 11/16/2022] Open
Abstract
The theoretical description of water properties continues to be a challenge. Using quantum cluster equilibrium (QCE) theory, we combine state-of-the-art quantum chemistry and statistical thermodynamic methods with the almost historical Clausius-Clapeyron relation to study water self-dissociation and the thermodynamics of vaporization. We pay particular attention to the treatment of internal rotations and their impact on the investigated properties by employing the modified rigid-rotor-harmonic-oscillator (mRRHO) approach. We also study a novel QCE parameter-optimization procedure. Both the ionic product and the vaporization enthalpy yield an astonishing agreement with experimental reference data. A significant influence of the mRRHO approach is observed for cluster populations and, consequently, for the ionic product. Thermodynamic properties are less affected by the treatment of these low-frequency modes.
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Affiliation(s)
- Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, Institute for Physical and Theoretical Chemistry, Beringstr. 4, 53115 Bonn, Germany
- Correspondence:
| | - Johannes Ingenmey
- CNRS, Physico-Chimie des Électrolytes et Nanosystèmes Interfaciaux, Sorbonne Université, F-75005 Paris, France;
| | - Michael von Domaros
- Department of Chemistry, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35032 Marburg, Germany;
| | - Eva Perlt
- Otto Schott Institute of Materials Research, Faculty of Physics and Astronomy, Friedrich-Schiller-Universität Jena, Löbdergraben 32, 07743 Jena, Germany;
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25
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Philippi F, Goloviznina K, Gong Z, Gehrke S, Kirchner B, Pádua AAH, Hunt PA. Charge transfer and polarisability in ionic liquids: a case study. Phys Chem Chem Phys 2022; 24:3144-3162. [PMID: 35040843 DOI: 10.1039/d1cp04592j] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The practical use of ionic liquids (ILs) is benefiting from a growing understanding of the underpinning structural and dynamic properties, facilitated through classical molecular dynamics (MD) simulations. The predictive and explanatory power of a classical MD simulation is inextricably linked to the underlying force field. A key aspect of the forcefield for ILs is the ability to recover charge based interactions. Our focus in this paper is on the description and recovery of charge transfer and polarisability effects, demonstrated through MD simulations of the widely used 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide [C4C1im][NTf2] IL. We study the charge distributions generated by a range of ab initio methods, and present an interpolation method for determining atom-wise scaled partial charges. Two novel methods for determining the mean field (total) charge transfer from anion to cation are presented. The impact of using different charge models and different partial charge scaling (unscaled, uniformly scaled, atom-wise scaled) are compared to fully polarisable simulations. We study a range of Drude particle explicitly polarisable potentials and shed light on the performance of current approaches to counter known problems. It is demonstrated that small changes in the charge description and MD methodology can have a significant impact; biasing some properties, while leaving others unaffected within the structural and dynamic domains.
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Affiliation(s)
- Frederik Philippi
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, White City Campus, London W12 0BZ, UK
| | - Kateryna Goloviznina
- Laboratoire de Chimie, École Normale Supérieure de Lyon & CNRS, 69364 Lyon, France
| | - Zheng Gong
- Laboratoire de Chimie, École Normale Supérieure de Lyon & CNRS, 69364 Lyon, France
| | - Sascha Gehrke
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstr. 4+6, D-53115 Bonn, Germany.,Department of Physics and Astronomy, University College London, London, WC1E 6BT, UK
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstr. 4+6, D-53115 Bonn, Germany
| | - Agílio A H Pádua
- Laboratoire de Chimie, École Normale Supérieure de Lyon & CNRS, 69364 Lyon, France
| | - Patricia A Hunt
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, White City Campus, London W12 0BZ, UK.,School of Chemical and Physical Sciences, Victoria University of Wellington, Wellington, New Zealand.
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26
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Abstract
The theoretical treatment of ionic liquids must focus now on more realistic models while at the same time keeping an accurate methodology when following recent ionic liquids research trends or allowing predictability to come to the foreground. In this Perspective, we summarize in three cases of advanced ionic liquid research what methodological progress has been made and point out difficulties that need to be overcome. As particular examples to discuss we choose reactions, chirality, and radicals in ionic liquids. All these topics have in common that an explicit or accurate treatment of the electronic structure and/or intermolecular interactions is required (accurate methodology), while at the same time system size and complexity as well as simulation time (realistic model) play an important role and must be covered as well.
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Affiliation(s)
- Barbara Kirchner
- 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
| | - Andreas Gansäuer
- Kekulé-Institut für Organische Chemie und Biochemie, University of Bonn, Gerhard-Domagk-Straße 1, D-53121 Bonn, Germany
| | - Oldamur Hollóczki
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstraße 4+6, D-53115 Bonn, Germany.,Department of Physical Chemistry, Faculty of Science and Technology, University of Debrecen, Egyetem tér 1, H-4010 Debrecen, Hungary
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27
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Abstract
This special cross-journal collection of Organic and Biomolecular Chemistry (OBC) and Physical Chemistry Chemical Physics (PCCP) is dedicated to non-traditional solvent effects in organic reactions.
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Affiliation(s)
- Jason B Harper
- School of Chemistry, University of New South Wales, Sydney, NSW, 2052, Australia.
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstraβe 4 + 6, D-53115 Bonn, Germany.
| | - Paulina Pavez
- Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Santiago 6094411, Chile.
| | - Tom Welton
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, White City Campus, London W12 0BZ, UK.
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28
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Ramos TN, Hollóczki O, Kirchner B, Champagne B. Self-aggregation of stilbazolium ion pairs in liquid chloroform. A molecular dynamics study. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.117735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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29
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Taherivardanjani S, Elfgen R, Reckien W, Suarez E, Perlt E, Kirchner B. Benchmarking the Computational Costs and Quality of Vibrational Spectra from Ab Initio Simulations. Advcd Theory and Sims 2021. [DOI: 10.1002/adts.202100293] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Shima Taherivardanjani
- Mulliken Center for Theoretical Chemistry Institute for Physical and Theoretical Chemistry Beringstr. 4 Bonn D‐53115 Germany
| | - Roman Elfgen
- Mulliken Center for Theoretical Chemistry Institute for Physical and Theoretical Chemistry Beringstr. 4 Bonn D‐53115 Germany
| | - Werner Reckien
- Mulliken Center for Theoretical Chemistry Institute for Physical and Theoretical Chemistry Beringstr. 4 Bonn D‐53115 Germany
| | - Estela Suarez
- Institute for Advanced Simulation Jülich Supercomputing Centre, Forschungszentrum Jülich GmbH Wilhelm‐Johnen‐Straße Jülich D‐52425 Germany
| | - Eva Perlt
- Otto Schott Institute of Materials Research Faculty of Physics and Astronomy Friedrich‐Schiller‐Universität Jena Löbdergraben 32 Jena D‐07743 Germany
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry Institute for Physical and Theoretical Chemistry Beringstr. 4 Bonn D‐53115 Germany
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30
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Marchelli G, Ingenmey J, Hollóczki O, Chaumont A, Kirchner B. Hydrogen Bonding and Vaporization Thermodynamics in Hexafluoroisopropanol-Acetone and -Methanol Mixtures. A Joined Cluster Analysis and Molecular Dynamic Study. Chemphyschem 2021; 23:e202100620. [PMID: 34632686 PMCID: PMC9298724 DOI: 10.1002/cphc.202100620] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 09/28/2021] [Indexed: 12/23/2022]
Abstract
Binary mixtures of hexafluoroisopropanol with either methanol or acetone are analyzed via classical molecular dynamics simulations and quantum cluster equilibrium calculations. In particular, their populations and thermodynamic properties are investigated with the binary quantum cluster equilibrium method, using our in‐house code peacemaker 2.8, upgraded with temperature‐dependent parameters. A novel approach, where the final density from classical molecular dynamics, has been used to generate the necessary reference isobars. The hydrogen bond network in both type of mixtures at molar fraction of hexafluoroisopropanol of 0.2, 0.5, and 0.8 respectively is investigated via the molecular dynamics trajectories and the cluster results. In particular, the populations show that mixed clusters are preferred in both systems even at 0.2 molar fractions of hexafluoroisopropanol. Enthalpies and entropies of vaporization are calculated for the neat and mixed systems and found to be in good agreement with experimental values.
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Affiliation(s)
- Gwydyon Marchelli
- Mulliken Center for Theoretical Chemistry, Rheinische Friedrich-Wilhelms-Universität Bonn, Beringstr. 4+6, D-53115, Bonn, Germany
| | - Johannes Ingenmey
- Mulliken Center for Theoretical Chemistry, Rheinische Friedrich-Wilhelms-Universität Bonn, Beringstr. 4+6, D-53115, Bonn, Germany
| | - Oldamur Hollóczki
- Mulliken Center for Theoretical Chemistry, Rheinische Friedrich-Wilhelms-Universität Bonn, Beringstr. 4+6, D-53115, Bonn, Germany
| | - Alain Chaumont
- Université de Strasbourg, CNRS, CMC UMR 7140, Laboratoire MSM, F-67000, Strasbourg, France
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, Rheinische Friedrich-Wilhelms-Universität Bonn, Beringstr. 4+6, D-53115, Bonn, Germany
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Zaby P, Ingenmey J, Kirchner B, Grimme S, Ehlert S. Calculation of improved enthalpy and entropy of vaporization by a modified partition function in quantum cluster equilibrium theory. J Chem Phys 2021; 155:104101. [PMID: 34525835 DOI: 10.1063/5.0061187] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
In this work, we present an altered partition function that leads to an improved calculation of the enthalpy and entropy of vaporization in the framework of quantum cluster equilibrium theory. The changes are based on a previously suggested modification [S. Grimme, Chem. Eur. J. 18, 9955-9964 (2012)] of the molecular entropy calculation in the gas phase. Here, the low energy vibrational frequencies in the vibrational partition function are treated as hindered rotations instead of vibrations. The new scheme is tested on a set of nine organic solvents for the calculation of the enthalpy and entropy of vaporization. The enthalpies and entropies of vaporization show improvements from 6.5 error to 3.3 kJ mol-1 deviation to experiment and from 28.4 error to 13.5 J mol-1 K-1 deviation to experiment, respectively. The effect of the corrected partition function is visible in the different populations of clusters, which become physically more meaningful in that larger clusters are higher populated in the liquid phase and the gas phase is mainly populated by the monomers. Furthermore, the corrected partition function also overcomes technical difficulties and leads to an increased stability of the calculations in regard to the size of the cluster set.
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Affiliation(s)
- Paul Zaby
- Mulliken Center for Theoretical Chemistry, University of Bonn, Bonn, Germany
| | - Johannes Ingenmey
- Mulliken Center for Theoretical Chemistry, University of Bonn, Bonn, Germany
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, University of Bonn, Bonn, Germany
| | - Stefan Grimme
- Mulliken Center for Theoretical Chemistry, University of Bonn, Bonn, Germany
| | - Sebastian Ehlert
- Mulliken Center for Theoretical Chemistry, University of Bonn, Bonn, Germany
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Szabadi A, Elfgen R, Macchieraldo R, Kearns FL, Lee Woodcock H, Kirchner B, Schröder C. Comparison between ab initio and polarizable molecular dynamics simulations of 1-butyl-3-methylimidazolium tetrafluoroborate and chloride in water. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.116521] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
Deep eutectic solvents as sustainable and new-generation solvents show potential in the field of cellulose dissolution. Although these novel materials are tested for numerous industrial, environmental, and medical applications, little is known about the structural features of cellulose interacting with deep eutectic solvents. In this work, the interplay of cellulose is studied in two deep eutectic solvents: choline acetate mixed with urea and choline chloride mixed with urea using classical molecular dynamics simulations. Dissolution of cellulose in the studied liquids was not observed to be in agreement with experimental work from the literature. However, a slight swelling in the chloride, as compared to the acetate-based solvent, is apparent. A possible rationale might be found in the stronger hydrogen bonding of the chloride anion compared to the acetate anion with the hydrogen atoms of the cellulose. Moreover, chloride approaches the outer glucose units comparatively more, which could be interpreted as the onset of entering and thus dissolving the cellulose as was previously observed. Specific hydrogen bonds between all units are analyzed and discussed in detail.
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Affiliation(s)
- Vahideh Alizadeh
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstraße 4+6, D-53115 Bonn, Germany
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstraße 4+6, D-53115 Bonn, Germany
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34
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Gehrke S, Ray P, Stettner T, Balducci A, Kirchner B. Water in Protic Ionic Liquid Electrolytes: From Solvent Separated Ion Pairs to Water Clusters. ChemSusChem 2021; 14:3315-3324. [PMID: 34169663 PMCID: PMC8456901 DOI: 10.1002/cssc.202100660] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 06/21/2021] [Indexed: 06/13/2023]
Abstract
The large electrochemical and cycling stability of "water-in-salt" systems have rendered promising prospective electrolytes for batteries. The impact of addition of water on the properties of ionic liquids has already been addressed in several publications. In this contribution, we focus on the changes in the state of water. Therefore, we investigated the protic ionic liquid N-butyl-pyrrolidinium bis(trifluoromethanesulfonyl)imide with varying water content at different temperatures with the aid of molecular dynamics simulations. It is revealed that at very low concentrations, the water is well dispersed and best characterized as shared solvent molecules. At higher concentrations, the water forms larger aggregates and is increasingly approaching a bulk-like state. While the librational and rotational dynamics of the water molecules become faster with increasing concentration, the translational dynamics are found to become slower. Further, all dynamics are found to be faster if the temperature increases. The trends of these findings are well in line with the experimental measured conductivities.
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Affiliation(s)
- Sascha Gehrke
- Mulliken Center for Theoretical ChemistryUniversity of BonnBeringstr. 4+6D-53115BonnGermany
- Department of Physics and AstronomyUniversity College LondonLondonWC1E 6BTUnited Kingdom
| | - Promit Ray
- Mulliken Center for Theoretical ChemistryUniversity of BonnBeringstr. 4+6D-53115BonnGermany
| | - Timo Stettner
- Institute for Technical Chemistry and Environmental ChemistryFriedrich-Schiller-University JenaPhilosophenweg 7aD-07743JenaGermany
- Center for Energy and Environmental Chemistry Jena (CEEC Jena)Friedrich-Schiller-University JenaPhilosophenweg 7aD-07743JenaGermany
| | - Andrea Balducci
- Institute for Technical Chemistry and Environmental ChemistryFriedrich-Schiller-University JenaPhilosophenweg 7aD-07743JenaGermany
- Center for Energy and Environmental Chemistry Jena (CEEC Jena)Friedrich-Schiller-University JenaPhilosophenweg 7aD-07743JenaGermany
| | - Barbara Kirchner
- Mulliken Center for Theoretical ChemistryUniversity of BonnBeringstr. 4+6D-53115BonnGermany
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Abstract
By simulating butan-2-ol dissolved in the chiral ionic liquid 1-ethyl-3-methylimidazolium (S)-alaninate, we investigate the chiral recognition of butan-2-ol in the ionic liquid. The hydrogen bonding between the chiral anion and both enantiomers of butan-2-ol is similar; however, both chiral molecules (anion and alcohol) induce an asymmetry in the achiral cation which leads to a more favorable environment for the alcohol in the heterochiral system as compared to the homochiral system and hence provides an energetic stabilization of the former.
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Affiliation(s)
- Jan Blasius
- Mulliken Center for Theoretical Chemistry, Rheinische Friedrich-Wilhelms-Universität Bonn, Beringstr. 4+6, D-53115 Bonn, Germany
| | - Paul Zaby
- Mulliken Center for Theoretical Chemistry, Rheinische Friedrich-Wilhelms-Universität Bonn, Beringstr. 4+6, D-53115 Bonn, Germany
| | - Oldamur Hollóczki
- Mulliken Center for Theoretical Chemistry, Rheinische Friedrich-Wilhelms-Universität Bonn, Beringstr. 4+6, D-53115 Bonn, Germany
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, Rheinische Friedrich-Wilhelms-Universität Bonn, Beringstr. 4+6, D-53115 Bonn, Germany
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Affiliation(s)
- Vahideh Alizadeh
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstraße 4+6, D-53115 Bonn, Germany
| | - Lars Esser
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstraße 4+6, D-53115 Bonn, Germany
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstraße 4+6, D-53115 Bonn, Germany
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Weber I, Ingenmey J, Schnaidt J, Kirchner B, Behm RJ. Influence of Complexing Additives on the Reversible Deposition/Dissolution of Magnesium in an Ionic Liquid. ChemElectroChem 2021. [DOI: 10.1002/celc.202001488] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Isabella Weber
- Institute of Surface Chemistry and Catalysis Ulm University Albert-Einstein-Allee 47 89081 Ulm Germany
- Helmholtz Institute Ulm (HIU) Electrochemical Energy Storage Helmholtzstraße 11 89081 Ulm Germany
- Karlsruhe Institute of Technology (KIT) P.O. Box 3640 76021 Karlsruhe Germany
| | - Johannes Ingenmey
- Mulliken Center for Theoretical Chemistry Bonn University Beringstraße 4 53114 Bonn Germany
| | - Johannes Schnaidt
- Institute of Surface Chemistry and Catalysis Ulm University Albert-Einstein-Allee 47 89081 Ulm Germany
- Helmholtz Institute Ulm (HIU) Electrochemical Energy Storage Helmholtzstraße 11 89081 Ulm Germany
- Karlsruhe Institute of Technology (KIT) P.O. Box 3640 76021 Karlsruhe Germany
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry Bonn University Beringstraße 4 53114 Bonn Germany
| | - R. Jürgen Behm
- Institute of Surface Chemistry and Catalysis Ulm University Albert-Einstein-Allee 47 89081 Ulm Germany
- Helmholtz Institute Ulm (HIU) Electrochemical Energy Storage Helmholtzstraße 11 89081 Ulm Germany
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38
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Esser L, Macchieraldo R, Elfgen R, Sieland M, Smarsly BM, Kirchner B. TiCl 4 Dissolved in Ionic Liquid Mixtures from ab Initio Molecular Dynamics Simulations. Molecules 2020; 26:molecules26010079. [PMID: 33375378 PMCID: PMC7795733 DOI: 10.3390/molecules26010079] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 12/15/2020] [Accepted: 12/16/2020] [Indexed: 11/22/2022] Open
Abstract
To gain a deeper understanding of the TiCl4 solvation effects in multi-component ionic liquids, we performed ab initio molecular dynamics simulations of 1-butyl-3-methylimidazolium [C4C1Im]+, tetrafluoroborate [BF4]−, chloride [Cl]− both with and without water and titanium tetrachloride TiCl4. Complex interactions between cations and anions are observed in all investigated systems. By further addition of water and TiCl4 this complex interaction network is extended. Observations of the radial distribution functions and number integrals show that water and TiCl4 not only compete with each other to interact mainly with [Cl]−, which strongly influences the cation-[BF4]− interaction, but also interact with each other, which leads to the fact that in certain systems the cation-anion interaction is enhanced. Further investigations of the Voronoi polyhedra analysis have demonstrated that water has a greater impact on the nanosegregated system than TiCl4 which is also due to the fact of the shear amount of water relative to all other components and its higher mobility compared to TiCl4. Overall, the polar network of the IL mixture collapses by including water and TiCl4. In the case of [Cl]− chloride enters the water continuum, while [BF4]− remains largely unaffected, which deeply affects the interaction of the ionic liquid (IL) network.
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Affiliation(s)
- Lars Esser
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstrasse 4+6, D-53115 Bonn, Germany; (L.E.); (R.M.); (R.E.)
| | - Roberto Macchieraldo
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstrasse 4+6, D-53115 Bonn, Germany; (L.E.); (R.M.); (R.E.)
| | - Roman Elfgen
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstrasse 4+6, D-53115 Bonn, Germany; (L.E.); (R.M.); (R.E.)
| | - Melanie Sieland
- Institute of Physical Chemistry, Justus Liebig University, Heinrich-Buff-Ring 17, D-35392 Giessen, Germany; (M.S.); (B.M.S.)
| | - Bernd Michael Smarsly
- Institute of Physical Chemistry, Justus Liebig University, Heinrich-Buff-Ring 17, D-35392 Giessen, Germany; (M.S.); (B.M.S.)
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstrasse 4+6, D-53115 Bonn, Germany; (L.E.); (R.M.); (R.E.)
- Correspondence:
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Kirchner B, Blasius J, Esser L, Reckien W. Predicting Vibrational Spectroscopy for Flexible Molecules and Molecules with Non‐Idle Environments. Advcd Theory and Sims 2020. [DOI: 10.1002/adts.202000223] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Barbara Kirchner
- Mulliken Center for Theoretical Chemistry Rheinische Friedrich‐Wilhelms‐Universität Bonn Beringstr. 4+6 D‐53115 Bonn Germany
| | - Jan Blasius
- Mulliken Center for Theoretical Chemistry Rheinische Friedrich‐Wilhelms‐Universität Bonn Beringstr. 4+6 D‐53115 Bonn Germany
| | - Lars Esser
- Mulliken Center for Theoretical Chemistry Rheinische Friedrich‐Wilhelms‐Universität Bonn Beringstr. 4+6 D‐53115 Bonn Germany
| | - Werner Reckien
- Mulliken Center for Theoretical Chemistry Rheinische Friedrich‐Wilhelms‐Universität Bonn Beringstr. 4+6 D‐53115 Bonn Germany
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Macchieraldo R, Ingenmey J, Kirchner B. Understanding the Complex Surface Interplay for Extraction: A Molecular Dynamics Study. Chemistry 2020; 26:14969-14977. [PMID: 32668054 PMCID: PMC7756757 DOI: 10.1002/chem.202002744] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2020] [Revised: 07/13/2020] [Indexed: 11/22/2022]
Abstract
By means of classical molecular dynamics simulation the interfacial properties of methanol and n‐dodecane, which are two potential candidate solvents for use in non‐aqueous liquid–liquid extraction, were assessed. The question of how the interface changes depending on the concentration of extractant (tri‐n‐butyl phosphate) and salt (LiCl) is addressed. Two different models to represent systems were used to evaluate how LiCl and tri‐n‐butyl phosphate affect mutual miscibility, and how the last‐named behaves depending on the chemical environment. Tri‐n‐butyl phosphate increases the mutual solubility of the solvents, whereas LiCl counteracts it. The extractant was found to be mostly adsorbed on the interface between the solvents, and therefore the structural features of the adsorption were investigated. Adsorption of tri‐n‐butyl phosphate changes depending on its concentration and the presence of LiCl. It exhibits a preferential orientation in which the butyl chains point at the n‐dodecane phase and the phosphate group points at the methanol phase. For high concentrations of tri‐n‐butyl phosphate, its molecular orientation is preserved by diffusion of the excess molecules into both the methanol and n‐dodecane phases. However, LiCl hinders the diffusion into the methanol phase, and thus increases the concentration of tri‐n‐butyl phosphate at the interface and forces a rearrangement with subsequent loss of orientation.
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Affiliation(s)
- Roberto Macchieraldo
- Mulliken Center for Theoretical Chemistry, Rheinische Friedrich-Wilhelms-Universität Bonn, Beringstrasse 4+6, 53115, Bonn, Germany
| | - Johannes Ingenmey
- Mulliken Center for Theoretical Chemistry, Rheinische Friedrich-Wilhelms-Universität Bonn, Beringstrasse 4+6, 53115, Bonn, Germany
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, Rheinische Friedrich-Wilhelms-Universität Bonn, Beringstrasse 4+6, 53115, Bonn, Germany
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41
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Affiliation(s)
- Jan Blasius
- Mulliken Center for Theoretical Chemistry, Rheinische Friedrich-Wilhelms-Universität Bonn, Beringstr. 4+6, D-53115 Bonn, Germany
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, Rheinische Friedrich-Wilhelms-Universität Bonn, Beringstr. 4+6, D-53115 Bonn, Germany
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Marchelli G, Ingenmey J, Kirchner B. Activity coefficients of binary methanol alcohol mixtures from cluster weighting. ChemistryOpen 2020; 9:774-785. [PMID: 32714740 PMCID: PMC7377217 DOI: 10.1002/open.202000171] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Revised: 06/16/2020] [Indexed: 11/10/2022] Open
Abstract
The hydrogen bond network of different small alcohols is investigated via cluster analysis. Methanol/alcohol mixtures are studied with increasing chain length and branching of the molecule. Those changes can play an important role in different fields, including solvent and metal extraction. The extended tight binding method GFN2-xTB allows the evaluation and geometry optimization of thousands of clusters built via a genetic algorithm. Interaction energies and geometries are evaluated and discussed for the neat systems. Thermodynamic properties, such as vaporization enthalpies and activity coefficients, are calculated with the binary quantum cluster equilibrium (bQCE) approach using our in-house code peacemaker 2.8. Combined distribution functions of the distances against the angles of the hydrogen bonds are evaluated for neat and mixed clusters and weighted by the equilibrium populations achieved from bQCE calculations.
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Affiliation(s)
- Gwydyon Marchelli
- Mulliken Center for Theoretical ChemistryRheinische Friedrich-Wilhelms-Universität BonnBeringstr. 4+6D-53115BonnGermany
| | - J. Ingenmey
- Mulliken Center for Theoretical ChemistryRheinische Friedrich-Wilhelms-Universität BonnBeringstr. 4+6D-53115BonnGermany
| | - B. Kirchner
- Mulliken Center for Theoretical ChemistryRheinische Friedrich-Wilhelms-Universität BonnBeringstr. 4+6D-53115BonnGermany
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Blasius J, Elfgen R, Hollóczki O, Kirchner B. Glucose in dry and moist ionic liquid: vibrational circular dichroism, IR, and possible mechanisms. Phys Chem Chem Phys 2020; 22:10726-10737. [PMID: 32150178 DOI: 10.1039/c9cp06798a] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ionic liquids and their mixtures with water show remarkable features in cellulose processing. For this reason, understanding the behavior of carbohydrates in ionic liquids is important. In the present study, we investigated three d-glucose isomers (α, β and open-chain) in 1-ethyl-3-methylimidazolium acetate in the presence and absence of water, through ab initio molecular dynamics simulations. In the complex hydrogen bonding network of these mixtures, the most interesting observation is that upon water addition every hydrogen bond elongates, except the glucose-glucose hydrogen bond for the open-chain and the α-form which shortens, clearly showing the beginning of the crystallization process. The ring glucose rearranges from on-top to in-plane and the open form changes from a coiled to a more linear arrangement when adding water which explains the contradiction that the center of mass distances of the glucose molecules with other glucose molecules grow while the hydrogen bonds shorten. The appearance of coiled open forms indicates that the previously suggested isomerization between these forms is possible and might play a role in the solubility of the related carbohydrates. The calculated IR and VCD spectra reveal insight into the intermolecular interactions, with good to excellent agreements with experimental spectra. Investigating the role of the cation, distances between the acidic carbon atom of the cation and the glucose carbon atom where ring closure and opening occurs are found, which are way shorter than dispersion-like interactions between aliphatic hydrocarbons.
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Affiliation(s)
- Jan Blasius
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstraße 4 + 6, D-53115 Bonn, Germany.
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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
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Clark R, von Domaros M, McIntosh AJS, Luzar A, Kirchner B, Welton T. Effect of an external electric field on the dynamics and intramolecular structures of ions in an ionic liquid. J Chem Phys 2019; 151:164503. [PMID: 31675893 DOI: 10.1063/1.5129367] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Simulations of the ionic liquid 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide in an external electric field have been performed using a Drude particle polarizable force field. The structure of the ions has been analyzed, with close attention paid to the configurations of the ions. The "charge arm" concept is used to explain certain changes of these configurations that would be difficult to rationalize otherwise, e.g., trans → cis isomerization of the bis(trifluoromethylsulfonyl)imide anion and extension of the alkyl chain of the cation. It has also been shown that the ions orient themselves so that their charge arms align with and stretch out along the field, and these effects occur at lower external electric field strengths than cause a change in the inherent diffusion of the ions. The dynamics of the system parallel and perpendicular to the field were analyzed, and it was found that the applied field affected the diffusion normal to the field. This is explained as a secondary effect of a change in the ion cage formed by the surrounding counterions of a given ion in the ionic liquid. The breakdown of the ion cages was rationalized by correlating changes to the inherent diffusion of the ions with other changes to the diffusion and bulk structure of the liquid, as well as considering the average forces on the ions compared to the force the ions would be expected to experience in an electric field. Parallel to the field, a drift was observed at every electric field studied. In electric fields with no changes to the ion cage structure, the relationship between the drift and electric field was found to be linear, becoming nonlinear as the ion cage structure breaks down.
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Affiliation(s)
- Ryan Clark
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, White City Campus, London W12 0BZ, United Kingdom
| | - Michael von Domaros
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstr. 4+6, D-53115 Bonn, Germany
| | - Alastair J S McIntosh
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, White City Campus, London W12 0BZ, United Kingdom
| | - Alenka Luzar
- Department of Chemistry, Virginia Commonwealth University, 1001 West Main St., Richmond, Virginia 23284-2006, USA
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstr. 4+6, D-53115 Bonn, Germany
| | - Tom Welton
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, White City Campus, London W12 0BZ, United Kingdom
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Stettner T, Gehrke S, Ray P, Kirchner B, Balducci A. Water in Protic Ionic Liquids: Properties and Use of a New Class of Electrolytes for Energy-Storage Devices. ChemSusChem 2019; 12:3827-3836. [PMID: 31237420 DOI: 10.1002/cssc.201901283] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Indexed: 06/09/2023]
Abstract
In this work, the properties of "water-in-PIL" (PIL=protic ionic liquid) electrolytes are reported based on 1-butylpyrrolidinium bis(trifluoromethanesulfonyl)imide (PyrH4 TFSI). Taking advantage of experimental and theoretical investigations, it is shown that the amount of water inside the electrolyte has a dramatic effect on the viscosity, conductivity, density, cation-anion interplay, and electrochemical stability of PyrH4 TFSI. The impact of water on the properties of this ionic liquid also affects its use as an electrolyte for electrochemical double-layer capacitors (EDLCs). It is shown that the presence of water improves the transport properties of PyrH4 TFSI, with a beneficial effect on the capacitance retention of the devices in which these electrolytes are used. However, at the same time, water reduces the operative voltage of EDLCs containing this PIL as the electrolyte and, furthermore, it has a strong impact on the inactive components of these systems. To suppress this latter problem, and to realize EDLCs with high stability, the use of inactive components stable in aqueous environment appears necessary.
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Affiliation(s)
- Timo Stettner
- Institute for Technical Chemistry and Environmental Chemistry, Friedrich Schiller University, Philosophenweg 7a, 07743, Jena, Germany
- Center for Energy and Environmental Chemistry Jena (CEEC Jena), Friedrich Schiller University, Philosophenweg 7a, 07743, Jena, Germany
| | - Sascha Gehrke
- Mulliken Center for Theoretical Chemistry, Rheinische Friedrich-Wilhelms-Universität, Beringstr. 4+6, 53115, Bonn, Germany
| | - Promit Ray
- Mulliken Center for Theoretical Chemistry, Rheinische Friedrich-Wilhelms-Universität, Beringstr. 4+6, 53115, Bonn, Germany
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, Rheinische Friedrich-Wilhelms-Universität, Beringstr. 4+6, 53115, Bonn, Germany
| | - Andrea Balducci
- Institute for Technical Chemistry and Environmental Chemistry, Friedrich Schiller University, Philosophenweg 7a, 07743, Jena, Germany
- Center for Energy and Environmental Chemistry Jena (CEEC Jena), Friedrich Schiller University, Philosophenweg 7a, 07743, Jena, Germany
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Alizadeh V, Geller D, Malberg F, Sánchez PB, Padua A, Kirchner B. Cover Feature: Strong Microheterogeneity in Novel Deep Eutectic Solvents (ChemPhysChem 14/2019). Chemphyschem 2019. [DOI: 10.1002/cphc.201900621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Vahideh Alizadeh
- Mulliken Center for Theoretical ChemistryUniversity of Bonn Beringstraße 4+6 D-53115 Bonn Germany
- Department of ChemistryInstitute for Advanced Studies in Basic Sciences (IASBS) Zanjan Iran
| | - David Geller
- Mulliken Center for Theoretical ChemistryUniversity of Bonn Beringstraße 4+6 D-53115 Bonn Germany
| | - Friedrich Malberg
- Mulliken Center for Theoretical ChemistryUniversity of Bonn Beringstraße 4+6 D-53115 Bonn Germany
| | - Pablo B. Sánchez
- Dpto. Física Aplicada, Facultad de CienciasUniversidad de Vigo Campus Lagoas-Marcosende s/n 36310 VIGO – Spain
| | - Agilio Padua
- École Normale Supérieure de LyonLaboratoire de Chimie 46 allée d'Italie 69364 Lyon cedex 07 France
| | - Barbara Kirchner
- Mulliken Center for Theoretical ChemistryUniversity of Bonn Beringstraße 4+6 D-53115 Bonn Germany
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Alizadeh V, Geller D, Malberg F, Sánchez PB, Padua A, Kirchner B. Strong Microheterogeneity in Novel Deep Eutectic Solvents. Chemphyschem 2019; 20:1786-1792. [DOI: 10.1002/cphc.201900307] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 05/16/2019] [Indexed: 12/13/2022]
Affiliation(s)
- Vahideh Alizadeh
- Mulliken Center for Theoretical ChemistryUniversity of Bonn Beringstraße 4+6 D-53115 Bonn Germany
- Department of ChemistryInstitute for Advanced Studies in Basic Sciences (IASBS) Zanjan Iran
| | - David Geller
- Mulliken Center for Theoretical ChemistryUniversity of Bonn Beringstraße 4+6 D-53115 Bonn Germany
| | - Friedrich Malberg
- Mulliken Center for Theoretical ChemistryUniversity of Bonn Beringstraße 4+6 D-53115 Bonn Germany
| | - Pablo B. Sánchez
- Dpto. Física Aplicada, Facultad de CienciasUniversidad de Vigo Campus Lagoas-Marcosende s/n 36310 VIGO – Spain
| | - Agilio Padua
- École Normale Supérieure de LyonLaboratoire de Chimie 46 allée d'Italie 69364 Lyon cedex 07 France
| | - Barbara Kirchner
- Mulliken Center for Theoretical ChemistryUniversity of Bonn Beringstraße 4+6 D-53115 Bonn Germany
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Macchieraldo R, Gehrke S, Batchu NK, Kirchner B, Binnemans K. Tuning Solvent Miscibility: A Fundamental Assessment on the Example of Induced Methanol/ n-Dodecane Phase Separation. J Phys Chem B 2019; 123:4400-4407. [PMID: 31032613 PMCID: PMC6590496 DOI: 10.1021/acs.jpcb.9b00839] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
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In
this work, we assess the fundamental aspects of mutual miscibility
of solvents by studying the mixing of two potential candidates, methanol
and n-dodecane, for nonaqueous solvent extraction.
To do so, 1H NMR spectroscopy and molecular dynamics simulations
are used jointly. The NMR spectra show that good phase separation
can be obtained by adding LiCl and that the addition of a popular
extractant (tri-n-butyl phosphate) yields the opposite
effect. It is also demonstrated that in a specific case the poor phase
separation is not due to the migration of n-dodecane
into the more polar phase, but due to the transfer of the extractant
into it, which is especially relevant when considering industrial
applications of solvent extraction. With the aid of molecular dynamics
simulations, explanations of this behavior are given. Specifically,
an increase of all hydrogen-bond lifetimes is found to be consequent
to the addition of LiCl which implies an indirect influence on the
methanol liquid structure, by favoring a stronger hydrogen-bond network.
Therefore, we found that better phase separation is not directly due
to the presence of LiCl, but due to the “hardening”
of the hydrogen-bond network.
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Affiliation(s)
- Roberto Macchieraldo
- Mulliken Center for Theoretical Chemistry , University of Bonn , Beringstrasse 4+6 , D-53115 Bonn , Germany
| | - Sascha Gehrke
- Mulliken Center for Theoretical Chemistry , University of Bonn , Beringstrasse 4+6 , D-53115 Bonn , Germany.,Max Planck Institute for Chemical Energy Conversion , Stiftstrasse 34-36 , D-45413 Mülheim an der Ruhr , Germany
| | - Nagaphani K Batchu
- Department of Chemistry , KU Leuven , Celestijnenlaan 200F, bus 2404 , B-3001 Heverlee , Belgium
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry , University of Bonn , Beringstrasse 4+6 , D-53115 Bonn , Germany
| | - Koen Binnemans
- Department of Chemistry , KU Leuven , Celestijnenlaan 200F, bus 2404 , B-3001 Heverlee , Belgium
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Abstract
A thorough analysis of molecular vibrations in the binary system hydrogen chloride/water is presented considering a set of small mixed and pure clusters. In addition to the conventional normal-mode analysis based on the diagonalization of the Hessian, anharmonic frequencies were obtained from the perturbative VPT2 and PT2-VSCF method using hybrid density functional theory. For all normal modes, potential energy curves were modeled by displacing the atoms from the minimum geometry along the normal mode vectors. Three model potentials, a harmonic potential, a Morse potential, and a fourth order polynomial, were applied to fit these curves. From these data, it was possible not only to characterize distinct vibrations as mainly harmonic, anharmonic, or involving higher order terms but also to extract force constants, k, and anharmonicity constants, xe. By investigating all different types of intramolecular vibrations including covalent stretching or bending vibrations and intermolecular vibrations such as librations, we could demonstrate that while vibrational frequencies can be obtained applying scaling factors to harmonic results, useful anharmonicity constants cannot be predicted in such a way and the usage of more elaborate vibrational methods is necessary. For each particular type of molecular vibration, we could however determine a relationship between the wavenumber or wavenumber shift and the anharmonicity constant, which allows us to estimate mode dependent anharmonicity constants for larger clusters in the future.
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Affiliation(s)
- Eva Perlt
- Department of Chemistry , University of California, Irvine , 1102 Natural Sciences II , Irvine , California 92697-2025 , United States
| | - Sarah A Berger
- Institute of Physical and Theoretical Chemistry, NAWI Graz , Graz University of Technology , Stremayrgasse 9 , 8010 Graz , Austria
| | - Anne-Marie Kelterer
- Institute of Physical and Theoretical Chemistry, NAWI Graz , Graz University of Technology , Stremayrgasse 9 , 8010 Graz , Austria
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry , University of Bonn , Beringstrasse 4 , D-53115 Bonn , Germany
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