Hi all. I'm trying to use IS to extract the ionic conductivity in light-emitting electrochemical cells based on ionic transition metal compounds, in particular an Ir(III) ionic complex dissolved in a volatile organic solvent and deposited by spin coating, enclosed between (hopefully) ion-blocking contacts. Sometimes a certain amount of ionic liquid is added to the solution. By performing IS on the final device I obtain spectra like the one attached (in the Bode form, conductance and capacitance are displayed vs. frequency). One of my colleagues told me that the feature of the conductance spectra enclosed in the ellipse should be due to the contribution of the ions to the conductivity. Now, I'm using the equivalent circuit in the figure to extract the ionic conductivity. What happens is: 1) the fits seem to be insensible to the value of Rion 2) the Rion that I obtain is almost always of the same order of magnitude of the Rel, the electron leakage. And that should not be. I feel that I'm doing something wrong, but can't see where the error lies. I would like someone with more experience to give me an hint that could point me in the right direction. Please, take in account that I'm a beginner in this field.

Thank you in advance. Have a nice day.