My samples are polymeric nanocomposite films. The data is in the from of real and imaginary parts of impedance.
Dear Muhammad,
You can calculate the dielectric constant from the capacity, which may be estimated from the imaginary part of the impedance Z". If you have a semi-circle you can use the maximum (or local maximum) and multiply this by 2(pi)f so you have an estimate of the capacity. If no semi-circle is apparent, such as you can look at the low frequency behavior and plot Z"against 2(pi)f. Of course there might be multiple time constants in your experiment with dielectric constants relating to the bulk solvent and the film respectively. In that case it might be helpful to consider an equivalent circuit (it's always helpful) which fits your data. Using different solvents may be useful to identify the different components of the system.
Best regards, Mike
You have to know the so-called geometrical capacitance (C0) as well. For parallel plate condensers or for coaxial cylinders it can be calculated from the area and the electrode distance.
What is the infomation yields the analizer? If it gives the capasitance of a mesuring cell, it allows to find only the module of dielectric constant. In this case you should find the phase shift to calculate the real and imaginary parts of permittivity (e=e'+je"). If the analizer expands e into e' and e", you should determine the padameters of the measuring cell, as said above.
Sample's thickness and area of parallel plates holder is known. For further clarification, I am attaching one file generated by our frequency response analyzer.
Thanks to all the ineterseted peoples.
Could you get me informztion about the type of yours anaslyser. I shell find the necessary information in i-net.
Best wishes.
Thakyou Dr. A A Lukichev for your interest
"Frequency Response/Impedance Vector Network Analyzer SA series" Core Technology group
Thakyou Dr. A A Lukichev for your interest
"Frequency Response/Impedance Vector Network Analyzer SA series" Core Technology group
I had a look at the data, but I had some difficulty in importing the file. In particular I'm not sure about the frequency. However assuming point 5 is measured at frequency of about 160 kHz, I find a capacity of about 100 pF for the first semi-circle (with some reservation). Did you perform multiple independent measurements (including different samples) of the polymer film?
Best regards, Mike
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