Estimation of Ionic Conductivity and Viscosity of Ionic Liquids Using a QSPR Model

Abstract

QSPR model for ionic conductivity and viscosity of ionic liquids were constructed using a polynomial expansion method. These equations could be applied to cations of alkyl amine, pyrrole, piperidine, pyridine, and imidazole, with the following anions: TFSI, Br, Cl, PF6, BF4, CF3SO3, CF3COO, CH3COO, CF3BF3, C2F5BF3, C3F7BF3, C4F9BF3, EtOSO3, C4F9SO3, CF3SO2NCOCF3, and C3F7COO. To determine the coefficients in nonlinear polynomial expansion equations, genetic algorithms were adapted. The calculated results gave a reasonable correlation accuracy of ionic conductivity and viscosity. After building the polynomial expansion equations, quantitative analyses were done for each descriptor, and the physicochemical meaning of each descriptor was examined. These results suggest that the ionic conductivity of each ionic liquid is governed not only as a liquid electrolyte but also as a solid electrolyte.