Improved united-atom force field for 1-Alkyl-3-methylimidazolium chloride

  • Liu Z
  • Chen T
  • Bell A
 et al. 
  • 58

    Readers

    Mendeley users who have this article in their library.
  • 47

    Citations

    Citations of this article.

Abstract

We have developed a united atom (UA) nonpolarizable force field for 1-alkyl-3-methyl-imidazolium chloride ([C(n)mim][Cl], n = 1, 2, 4, 6, 8), a potential solvent for the pretreatment of lignocellulosic biomass. The charges were assigned by fitting the electrostatic potential surface (ESP) of the ion pair dimers. The Lennard-Jones parameters of the hydrogen atoms on the imidazolium ring were adjusted to agree with the ab initio optimized geometries of isolated ion pairs. Molecular dynamics (MD) simulations were performed for a wide range of temperatures to validate the force field. Substantial improvements were found in both the dynamical properties and the fluid structures, as compared to those predicted using our previously developed UA force field (UA2006) (Phys. Chem. Chem. Phys. 2006, 8, 1096). Liquid densities were found to lie within 2% experimental data. The simulated heats of vaporization decreased about 30% relative to that predicted using the UA2006 force field. The site-site radial distribution functions between the hydrogen atoms on the imidazolium ring and the chloride anions were in good agreement with those determined by ab initio molecular dynamics. The newly developed force field gives a much better description of the self-diffusion coefficients and shear viscosities, which usually deviate by 1 order of magnitude when determined using other force fields.

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document

Authors

  • Alexis BellUniversity of California Berekeley Department of Chemical and Biomolecular Engineering

    Follow
  • Zhiping Liu

  • Ting Chen

  • Berend Smit

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free