Molecular Dynamics Simulations of n-Hexane at 1-Butyl-3-Methylimidazolium bis(trifluoromethylsulfonyl) Imide Interface

0394742 - ÚCHP 2014 RIV US eng J - Journal Article
Lísal, Martin - Izák, Pavel
Molecular Dynamics Simulations of n-Hexane at 1-Butyl-3-Methylimidazolium bis(trifluoromethylsulfonyl) Imide Interface.
Journal of Chemical Physics. Roč. 139, č. 1 (2013), 014704. ISSN 0021-9606. E-ISSN 1089-7690
R&D Projects: GA ČR(CZ) GAP106/12/0569; GA MŠMT LH12020
Institutional support: RVO:67985858
Keywords : temperature ionic liquids * electric double-layer * rutile 110 surface
Subject RIV: CF - Physical ; Theoretical Chemistry
Impact factor: 3.122, year: 2013

Molecular dynamics simulations of n-hexane adsorbed onto the interface of 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide ([bmim][Tf2N]) are performed at three n-hexane surface densities, ranged from 0.7 to 2.3 mu mol/m(2) at 300 K. For [bmim][Tf2N] room-temperature ionic liquid, we use a non-polarizable all-atom force field with the partial atomic charges based on ab initio calculations for the isolated ion pair. The net charges of the ions are +/- 0.89e, which mimics the anion to cation charge transfer and polarization effects. The OPLS-AA force field is employed for modeling of n-hexane. The surface tension is computed using the mechanical route and its value decreases with increase of the n-hexane surface density. The [bmim][Tf2N]/n-hexane interface is analyzed using the intrinsic method, and the structural and dynamic properties of the interfacial, sub-interfacial, and central layers are computed. We determine the surface roughness, global and intrinsic density profiles, and orientation ordering of the molecules to describe the structure of the interface. We further compute the survival probability, normal and lateral self-diffusion coefficients, and re-orientation correlation functions to elucidate the effects of n-hexane on dynamics of the cations and anions in the layers.
Permanent Link: http://hdl.handle.net/11104/0222916