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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] [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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2
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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] [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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3
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Frömbgen T, Blasius J, Alizadeh V, Chaumont A, Brehm M, Kirchner B. Cluster Analysis in Liquids: A Novel Tool in TRAVIS. J Chem Inf Model 2022; 62:5634-5644. [PMID: 36315975 DOI: 10.1021/acs.jcim.2c01244] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We present a novel cluster analysis implemented in our open-source software TRAVIS and its application to realistic and complex chemical systems. The underlying algorithm is exclusively based on atom distances. Using a two-dimensional model system, we first introduce different cluster analysis functions and their application to single snapshots and trajectories including periodicity and temporal propagation. Using molecular dynamics simulations of pure water with varying system size, we show that our cluster analysis is size-independent. Furthermore, we observe a similar clustering behavior of pure water in classical and ab initio molecular dynamics simulations, showing that our cluster analysis is universal. In order to emphasize the application to more complex systems and mixtures, we additionally apply the cluster analysis to ab initio molecular dynamics simulations of the [C2C1Im][OAc] ionic liquid and its mixture with water. Using that, we show that our cluster analysis is able to analyze the clustering of the individual components in a mixture as well as the clustering of the ionic liquid with water.
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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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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] [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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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] [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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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: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [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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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] [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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8
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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: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [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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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] [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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Kirchner B, Blasius J, Esser L, Reckien W. Predicting Vibrational Spectroscopy for Flexible Molecules and Molecules with Non‐Idle Environments. ADVANCED THEORY AND SIMULATIONS 2020. [DOI: 10.1002/adts.202000223] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [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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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: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [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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