Wilhelm-Ostwald-Institut für Physikalische und Theoretische Chemie, Universität Leipzig, Linnéstr. 2, D-04103 Leipzig, Germany.
Chemphyschem. 2012 May 14;13(7):1845-53. doi: 10.1002/cphc.201100917. Epub 2012 Mar 1.
We present a comprehensive density functional study, using the Perdew-Burke-Ernzerhof (PBE) functional, to elucidate the effect of including or neglecting the dispersion correction on the structure and dynamics of the ionic liquid 1-ethyl-3-methylimidazolium thiocyanate. We have investigated the structure of the liquid phase and observed that specific interactions between the anions and cations of the ionic liquid were not accurately represented if the dispersion was neglected. The dynamics of the system is more accurately described if the dispersion correction is taken into account and its omission also leads to an incorrect representation of the hydrogen-bonding dynamics. Finally, the power spectrum is predicted and in good agreement with experimental results. Thus, we conclude that it is possible to represent the structure and dynamics of systems containing ionic liquids accurately using ab initio molecular dynamics and a correction for dispersion.
我们使用 Perdew-Burke-Ernzerhof（PBE）泛函进行了全面的密度泛函研究，以阐明在结构和动力学研究中包含或忽略色散校正对 1-乙基-3-甲基咪唑𬭩硫氰酸盐离子液体的影响。我们研究了液相的结构，并观察到如果忽略色散，离子液体的阴阳离子之间的特定相互作用将无法准确表示。如果考虑到色散校正，则可以更准确地描述系统的动力学，而忽略它也会导致对氢键动力学的不正确表示。最后，预测了功率谱，并与实验结果吻合良好。因此，我们得出结论，使用从头算分子动力学和色散校正可以准确表示包含离子液体的系统的结构和动力学。
