Structure and dynamics in protic ionic liquids: A combined optical Kerr-effect and dielectric relaxation spectroscopy study

Abstract

The structure and dynamics of ionic liqs. (ILs) are unusual due to the strong interactions between the ions and counter ions. These microscopic properties det. the bulk transport properties crit. to applications of ILs such as advanced fuel cells. The terahertz dynamics and slower relaxations of simple alkylammonium nitrate protic ionic liqs. (PILs) are here studied using femtosecond optical Kerr-effect spectroscopy, dielec. relaxation spectroscopy, and terahertz time-domain spectroscopy. The obsd. dynamics give insight into more general liq. behavior while comparison with glass-forming liqs. reveals an underlying power-law decay and relaxation rates suggest supramol. structure and nanoscale segregation.