The motivation for this study came from measurements of dielectric material on a Novocontrol Technologies dielectric spectrometer. Just like in electrochemicqal spectroscopy the instrument can provide output of real and imaginary impedance, but it conveniently provides direct output of permittivity values, for example. It is these features that lead us to realize that under incorrect assumptions interpretation of the results can lead to erroneous conclusions about material properties. An example of apparent frequency-dependent material permittivity will be provided.

In order to reduce the vast volume of impedance output data (e.g., autonomous recording of e.g., frequency spectrum swept over wide temperature range) we tried recently emerging approach of data treatment, DRT. DRT - distribution of relaxation times can simplify initial data survey evaluation as it does not require any a priori assumption about an equivalent circuit, for example. In this abstract is an illustration of a result obtained from a particular dielectric medium studied at various temperatures, evaluated by (a) calculating its capacitance from impedance data and (b) by applying the DRT evaluation routine. The similarity of the two graphs should be apparent; the absolute values of the y scales are however different as they represent different parameters.

Acknowledgments

This work was supported by a specific research grant of the Brno Technical University; project FEKT-S-20-62060 and in part by the Czech Science Foundation project GA ČR GA19-23718S.

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