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Citation
Tags
HERO ID
3860592
Reference Type
Journal Article
Title
Perfluoropolyethers: Development of an All-Atom Force Field for Molecular Simulations and Validation with New Experimental Vapor Pressures and Liquid Densities
Author(s)
Black, JE; Silva, GMC; Klein, C; Iacovella, CR; Morgado, P; Martins, LFG; Filipe, EJM; Mccabe, C
Year
2017
Is Peer Reviewed?
Yes
Journal
Journal of Physical Chemistry B
ISSN:
1520-6106
EISSN:
1520-5207
Publisher
AMER CHEMICAL SOC
Location
WASHINGTON
Volume
121
Issue
27
Page Numbers
6588-6600
Language
English
PMID
28557461
DOI
10.1021/acs.jpcb.7b00891
Web of Science Id
WOS:000405764000015
Abstract
A force field for perfluoropolyethers (PFPEs) based on the general optimized potentials for liquid simulations all-atom (OPLS-AA) force field has been derived in conjunction with experiments and ab initio quantum mechanical calculations. Vapor pressures and densities of two liquid PFPEs, perfluorodiglyme (CF3-O-(CF2-CF2-O)2-CF3) and perfluorotriglyme (CF3-O-(CF2-CF2-O)3-CF3), have been measured experimentally to validate the force field and increase our understanding of the physical properties of PFPEs. Force field parameters build upon those for related molecules (e.g., ethers and perfluoroalkanes) in the OPLS-AA force field, with new parameters introduced for interactions specific to PFPEs. Molecular dynamics simulations using the new force field demonstrate excellent agreement with ab initio calculations at the RHF/6-31G* level for gas-phase torsional energies (<0.5 kcal mol(-1) error) and molecular structures for several PFPEs, and also accurately reproduce experimentally determined densities (<0.02 g cm(-3) error) and enthalpies of vaporization derived from experimental vapor pressures (<0.3 kcal mol(-1)). Additional comparisons between experiment and simulation show that polyethers demonstrate a significant decrease in enthalpy of vaporization upon fluorination unlike related molecules (e.g., alkanes and alcohols). Simulation suggests this phenomenon is a result of reduced cohesion in liquid PFPEs due to a reduction in localized associations between backbone oxygen atoms and neighboring molecules.
Tags
PFAS
•
Additional PFAS (formerly XAgency)
Literature Search November 2019
PubMed
Web of Science
Not prioritized for screening
Perfluoropentanesulfonic acid
•
Expanded PFAS SEM (formerly PFAS 430)
Perfluoropentanesulfonate
•
^Per- and Polyfluoroalkyl Substances (PFAS)
PFPeS (2706-91-4)
Literature Search
Pubmed
•
PFPeS
Literature Search
Pubmed
Screening Results
Excluded/Not on Topic
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