Conductivity and Solvation Dynamics in Ionic Liquids

It was shown recently that a simple dielectric continuum model predicts the integral solvation time of a dipolar solute to be inversely proportional to the electrical conductivity cro of an ionic solvent or solution. In this Letter, we provide a more general derivation of this connection and show that available data on coumarin 153 (C153) in ionic liquids generally support this prediction. The relationship between solvation time and conductivity can be expressed by In(/ps) = 4.37 - 0.92 In (sigma(0)/S m(-1)) in 34 common ionic liquids.