Extending the compensated Arrhenius formalism to concentrated alcohol electrolytes: Arrhenius vs. non-Arrhenius behavior

The compensated Arrhenius formalism is applied to ionic conductivities in alcohol-based electrolytes at concentrations where the salt makes a non-negligible contribution to the static dielectric constant of the solution. The temperature-dependent behavior of the conductivity depends on the amount of added salt. Non-Arrhenius behavior is observed for low to moderate salt concentrations, while Arrhenius behavior occurs at high concentrations. The compensated Arrhenius formalism provides insight into this behavior by analyzing the effect of salt concentration on the temperature dependence of the exponential prefactor. When the compensated Arrhenius prefactors are plotted against the solution static dielectric constants using the Ea obtained from the compensated Arrhenius equation, the prefactors lie on a single master curve. In contrast, a similar plot based on the Ea obtained from a simple Arrhenius plot of the same conductivity data does not yield a master curve.Application of the compensated Arrhenius formalism requires the construction of a reference curve. It is essential that the range of static dielectric constant values spanned by the reference curve encompasses the range of temperature-dependent static dielectric constant values of the selected alcohol electrolyte. This will allow an accurate interpolation to obtain the appropriate reference conductivity. A detailed description is given for the method used to construct an appropriate reference conductivity curve.