Volume 154, 2012

Critical behaviour and vapour-liquid coexistence of 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide ionic liquidsvia Monte Carlo simulations

Abstract

Atomistic Monte Carlo simulations are used to compute vapour–liquid coexistence properties of a homologous series of [Cnmim][NTf2] ionic liquids, with n = 1, 2, 4, 6. Estimates of the critical temperatures range from 1190 K to 1257 K, with longer cation alkyl chains serving to lower the critical temperature. Other quantities such as critical density, critical pressure, normal boiling point, and accentric factor are determined from the simulations. Vapour pressure curves and the temperature dependence of the enthalpy of vapourisation are computed and found to have a weak dependence on the length of the cation alkyl chain. The ions in the vapour phase are predominately in single ion pairs, although a significant number of ions are found in neutral clusters of larger sizes as temperature is increased. It is found that previous estimates of the critical point obtained from extrapolating experimental surface tension data agree reasonably well with the predictions obtained here, but group contribution methods and primitive models of ionic liquids do not capture many of the trends observed in the present study

Supplementary files

Article information

Article type
Paper
Submitted
05 May 2011
Accepted
01 Jun 2011
First published
23 Sep 2011

Faraday Discuss., 2012,154, 53-69

Critical behaviour and vapour-liquid coexistence of 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide ionic liquids via Monte Carlo simulations

N. Rai and E. J. Maginn, Faraday Discuss., 2012, 154, 53 DOI: 10.1039/C1FD00090J

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements