Molecular dynamics study of the ionic liquid 1-n-butyl-3-methylimidazolium hexafluorophosphate

We report the results of a molecular, dynamics study of the ionic liquid 1-n-butyl-3-methylimidazolium hexafluorophosphate [bmim][PF6], a widely studied ionic liquid. An all-atom force field is developed using a combination of density functional theory calculations and CHARMM 22 parameter values. Molecular dynamics simulations are carried out in the isothermal-isobaric ensemble at three different temperatures. Quantities computed include infrared frequencies, molar volumes, volume expansivities, isothermal compressibililties, self-diffusivities, cation-anion exchange rates, rotational dynamics, and radial distribution functions. Computed thermodynamic properties are in good agreement with available experimental values.