Thermodynamic, Dynamic, and Structural Properties of Ionic Liquids Comprised of 1-butyl-3-methylimidazolium Cation and Nitrate, Azide, or Dicyanamide Anions

摘要

Molecular dynamics simulations ionic liquids comprised of (bmim) cation and nitrate (NO3), azide (N3), or dicyanamide (N(CN)2) anions were conducted using the polarizable APPLE&P force field. Comparison of thermodynamic properties such as densities, enthalpies of vaporization, and ion binding energies as well as structural correlations obtained from simulations at atmospheric pressure and temperature range 298-393 K showed that IL with the N(CN)2 anion shows significantly different characteristics compared to ILs with the N3 and NO3 anions. This trend is further manifested in dynamical properties characterized by self-diffusion coefficients and molecular rotational relaxation times. We also examine the dynamic correlations between the ions' translational and rotational motions as well as discuss the anisotropy of the latter.