Solvation free energies of ion dissociations in dichloromethane: En route to accurate computations
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Autor:in (Körperschaft)
Publikationsdatum
13.06.2025
Typ der Arbeit
Studiengang
Typ
01A - Beitrag in wissenschaftlicher Zeitschrift
Herausgeber:innen
Herausgeber:in (Körperschaft)
Betreuer:in
Übergeordnetes Werk
Journal of Physical Chemistry B
Themenheft
DOI der Originalpublikation
Link
Reihe / Serie
Reihennummer
Jahrgang / Band
129
Ausgabe / Nummer
25
Seiten / Dauer
6276-6288
Patentnummer
Verlag / Herausgebende Institution
American Chemical Society
Verlagsort / Veranstaltungsort
Auflage
Version
Programmiersprache
Abtretungsempfänger:in
Praxispartner:in/Auftraggeber:in
Zusammenfassung
Calculating accurate free energies for solution-phase reactions is notoriously difficult. In our previous joint experimental and computational studies, we observed a striking failure of quantum mechanical calculations with popular implicit solvent models to even qualitatively reproduce the experimental trends of dissociation free energies of numerous proton-bound pyridine dimers in organic solvents [Pollice, R. . J. Am. Chem. Soc. 2017, 139(37), 13126–13140]; [Pollice, R. . Angew. Chem., Int. Ed. 2019, 58(40), 14281–14288]. In this article, we expand the computational study of the dissociation of proton-bound pyridine dimers in the gas phase and in dichloromethane (DCM). In an effort to determine the prerequisites for reproducing the experimental trends and magnitudes of the dissociation free energies (ΔGdiss) in solvent, we investigated the impact of accounting for the ensemble free energy, umbrella sampling, thermodynamic integration, and explicit solvation using semiempirical quantum mechanics and molecular mechanics. We estimated the effect of conformational free energy contributions with semiempirical quantum mechanics (SE). Molecular dynamics (MD) with explicit solvation and classical molecular mechanics (MM) was used as a method to treat not only the solute but also the solvent configurational entropy. We found that explicit solvation with MM is indeed capable of reproducing ΔGdiss in DCM for our test system within an acceptable error margin. We analyze and discuss the results and limitations of our approach for calculating the solvation free energy.
Schlagwörter
Chemical calculations, Free energy, Oligomers, Solvation, Solvents
Fachgebiet (DDC)
Veranstaltung
Startdatum der Ausstellung
Enddatum der Ausstellung
Startdatum der Konferenz
Enddatum der Konferenz
Datum der letzten Prüfung
ISBN
ISSN
1520-6106
1520-5207
1520-5207
Sprache
Englisch
Während FHNW Zugehörigkeit erstellt
Ja
Zukunftsfelder FHNW
Publikationsstatus
Veröffentlicht
Begutachtung
Peer-Review der ganzen Publikation
Open Access-Status
Closed
Lizenz
Zitation
Savoy, A., Paenurk, E., Pollice, R., Hünenberger, P. H., & Chen, P. (2025). Solvation free energies of ion dissociations in dichloromethane: En route to accurate computations. Journal of Physical Chemistry B, 129(25), 6276–6288. https://doi.org/10.1021/acs.jpcb.5c01446