Comments on the fitting of Cole-Cole/Havriliak-Negami equation with the dielectric data under the influence of parasitic effects in order to extract correct parameters of the materials

Extracting correct results from the electrical data acquired from the measuring instruments are many times very tedious exercise. Most often extreme low and high frequency measured data are affected due to the parasitic combined effects of resistance, inductance of connecting wires and capacitance between them, electrode resistance, ionic conductivity of the materials, electrodes polarization effect and many more. Due to these parasitic effects/artefacts, sometimes even negative values of the capacitance/permittivity and resistance/loss are observed and we inadvertently relate these values with the unusual properties of the materials. Proper presentation of the experimental data with the existing models like Cole-Cole or Havriliak-Negami equation is also equally important. If presentation is not proper then it is very difficult to draw appropriate conclusion. Here, errors in the reporting of the experimental data in the light of above issues are discussed which would be useful for researchers working in the area of dielectric properties of the materials. (C) 2021 Elsevier B.V. All rights reserved.