SAFT-γ force field for the simulation of molecular fluids: 8. Hetero-segmented coarse-grained models of perfluoroalkylalkanes assessed with new vapour–liquid interfacial tension data. (16th September 2016)

• Record Type: Journal Article
• Authors: Morgado, Pedro; Lobanova, Olga; Müller, Erich A.; Jackson, George; Almeida, Miguel; Filipe, Eduardo J. M.
• Is Part Of: Molecular physics. Volume 114:Number 18(2016)
• Page Start: 2597
• Page End: 2614
• Publication Date: 2016-09-16
• Subjects: Molecular simulation -- interfacial properties -- intermolecular potential -- coarse graining; Molecules -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Molécules -- Périodiques; Chimie physique et théorique -- Périodiques; 539.6.05
• DOI: 10.1080/00268976.2016.1218077
• Languages: English
• ISSNs: 0026-8976

Abstract

ABSTRACT: The air–liquid interfacial behaviour of linear perfluoroalkylalkanes (PFAAs) is reported through a combined experimental and computer simulation study. The surface tensions of seven liquid PFAAs (perfluorobutylethane, F4 H2 ; perfluorobutylpentane, F4 H5 ; perfluorobutylhexane, F4 H6, perfluorobutyloctane, F4 H8 ; perfluorohexylethane, F6 H2 ; perfluorohexylhexane, F6 H6 ; and perfluorohexyloctane, F6 H8 ) are experimentally determined over a wide temperature range (276–350 K). The corresponding surface thermodynamic properties and the critical temperatures of the studied compounds are estimated from the temperature dependence of the surface tension. Experimental density and vapour pressure data are employed to parameterize a generic heteronuclear coarse-grained intermolecular potential of the SAFT-γ family for PFAAs. The resulting force field is used in direct molecular-dynamics simulations to predict the experimental tensions with quantitative agreement and to explore the conformations of the molecules in the interfacial region revealing a preferential alignment of the PFAA molecules towards the interface and an enrichment of the perfluoro groups at the outer interface region. Abstract :