Comment on 'relaxation spectroscopy of electrolyte solutions: LiClO4 in tetraethyleneglycol dimethylether'

The frequency dependent complex permittivity of LiClO4 solutions in tetraethyleneglycol dimethylether (tetraglyme) with concentrations up to 1.5 mol/1 is measured at 20 °C over a broad frequency range (5 MHz to 72 GHz). Apart from the conductivity contribution, there are two distinguishable absorption regions. The relaxation at higher frequencies is due to the solvent. The lower frequency feature is due to ionic processes. It comprises two spectral components, which both are unlikely to be caused by rotational tumbling motion of well-defined ionic species (e.g. ion pairs) but rather seem to involve some other processes such as confined translational modes of ionic motion.