Artículo
Abstract:
Acid ionization in aprotic media is studied using molecular dynamics techniques. In particular, models for HCl ionization in acetonitrile and dimethylsulfoxide are investigated. The proton is treated quantum mechanically using Feynman path integral methods and the remaining molecules are treated classically. Quantum effects are shown to be essential for the proper treatment of the ionization. The potential of mean force is computed as a function of the ion pair separation and the local solvent structure is examined. The computed dissociation constants in both solvents differ by several orders of magnitude which are in reasonable agreement with experimental results. Solvent separated ion pairs are found to exist in dimethylsulfoxide but not in acetonitrile. Dissociation mechanisms in small clusters are also investigated. Solvent separated ion pairs persist even in aggregates composed of rather few molecules, for instance, as few as 30 molecules. For smaller clusters or for large ion pair separations cluster finite-size effects come into play in a significant fashion. © 1996 American Institute of Physics.
Registro:
| Documento: | Artículo |
| Título: | Molecular dynamics study of solvation effects on acid dissociation in aprotic media |
| Autor: | Laria, D.; Kapral, R.; Estrin, D.; Ciccotti, G. |
| Filiación: | Departamento Química de Reactores, Comisión National de Energía Atómica, 1429 Capital Federal, Argentina Chemical Physics Theory Group, Department of Chemistry, University of Toronto, Toronto, Ont. M5S 1A1, Canada INQUIMAE, Facultad de Ciencias Exactas y Naturales, Pabellón II, 1428 Capital Federal, Argentina Dipartimento di Fisica, Università La Sapienza, Piazzale Aldo Mow, 2, 00185 Roma, Italy |
| Año: | 1996 |
| Volumen: | 104 |
| Número: | 17 |
| Página de inicio: | 6560 |
| Página de fin: | 6568 |
| DOI: | http://dx.doi.org/10.1063/1.471375 |
| Título revista: | Journal of Chemical Physics |
| Título revista abreviado: | J Chem Phys |
| ISSN: | 00219606 |
| CODEN: | JCPSA |
| Registro: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00219606_v104_n17_p6560_Laria |
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Citas:
---------- APA ----------
Laria, D., Kapral, R., Estrin, D. & Ciccotti, G. (1996) . Molecular dynamics study of solvation effects on acid dissociation in aprotic media. Journal of Chemical Physics, 104(17), 6560-6568.http://dx.doi.org/10.1063/1.471375
---------- CHICAGO ----------
Laria, D., Kapral, R., Estrin, D., Ciccotti, G. "Molecular dynamics study of solvation effects on acid dissociation in aprotic media" . Journal of Chemical Physics 104, no. 17 (1996) : 6560-6568.http://dx.doi.org/10.1063/1.471375
---------- MLA ----------
Laria, D., Kapral, R., Estrin, D., Ciccotti, G. "Molecular dynamics study of solvation effects on acid dissociation in aprotic media" . Journal of Chemical Physics, vol. 104, no. 17, 1996, pp. 6560-6568.http://dx.doi.org/10.1063/1.471375
---------- VANCOUVER ----------
Laria, D., Kapral, R., Estrin, D., Ciccotti, G. Molecular dynamics study of solvation effects on acid dissociation in aprotic media. J Chem Phys. 1996;104(17):6560-6568.http://dx.doi.org/10.1063/1.471375
