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Aqueous partial molar volumes from simulation and individual group contributions / Ashish V. Sangwai in Industrial & engineering chemistry research, Vol. 47 n°15 (Août 2008) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 47 n°15 (Août 2008) . - p. 5169–5174 Titre : Aqueous partial molar volumes from simulation and individual group contributions Type de document : texte imprimé Auteurs : Ashish V. Sangwai, Auteur ; Henry S. Ashbaugh, Auteur Année de publication : 2008 Article en page(s) : p. 5169–5174 Note générale : Bibliogr. p. 5174 Langues : Anglais (eng) Mots-clés : Partial  molar  volumes;  Kirkwood−Buff  theory Résumé : Partial molar volumes (PMVs) for a range of organic solutes in aqueous solution are evaluated from molecular simulations using Kirkwood−Buff theory. Long-range oscillatory variations in the Kirkwood−Buff integrals are suppressed using the techniques of Lockwood, Rossky, and Levy [J. Phys. Chem. B, 1999, 103, 1982−1990 and J. Phys. Chem. B, 2000, 104, 4210−4217], enhancing convergence of the calculated partial molar volumes to within the first hydration shell. Contributions from individual constituent groups, such as methylene carbons and alcohol oxygens, are evaluated using proximal correlation functions extended here to heterogeneous molecular species. We find the simulation partial molar volumes are systematically greater than experiment, with the difference between simulation and experiment increasing with solute size. These differences are attributed to possible deficiencies in the volumetric properties of the interaction potentials employed. Nevertheless, we find that the structure of water near identical groups on different solutes is effectively indistinguishable, as quantified by proximal correlation functions. As a result, we propose a new group contribution correlation for the PMV rooted in Kirkwood−Buff theory and the proximity approximation. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie0714448 [article] Aqueous partial molar volumes from simulation and individual group contributions [texte imprimé] / Ashish V. Sangwai, Auteur ; Henry S. Ashbaugh, Auteur . - 2008 . - p. 5169–5174. Bibliogr. p. 5174 Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 47 n°15 (Août 2008) . - p. 5169–5174 Mots-clés : Partial  molar  volumes;  Kirkwood−Buff  theory Résumé : Partial molar volumes (PMVs) for a range of organic solutes in aqueous solution are evaluated from molecular simulations using Kirkwood−Buff theory. Long-range oscillatory variations in the Kirkwood−Buff integrals are suppressed using the techniques of Lockwood, Rossky, and Levy [J. Phys. Chem. B, 1999, 103, 1982−1990 and J. Phys. Chem. B, 2000, 104, 4210−4217], enhancing convergence of the calculated partial molar volumes to within the first hydration shell. Contributions from individual constituent groups, such as methylene carbons and alcohol oxygens, are evaluated using proximal correlation functions extended here to heterogeneous molecular species. We find the simulation partial molar volumes are systematically greater than experiment, with the difference between simulation and experiment increasing with solute size. These differences are attributed to possible deficiencies in the volumetric properties of the interaction potentials employed. Nevertheless, we find that the structure of water near identical groups on different solutes is effectively indistinguishable, as quantified by proximal correlation functions. As a result, we propose a new group contribution correlation for the PMV rooted in Kirkwood−Buff theory and the proximity approximation. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie0714448