Greetings. I don't know how to use an equation with a complex frequency term, specifically this one (aka Debye expression) for frequency-dependent permittivity:(adsbygoogle = window.adsbygoogle || []).push({});

epsilon(omega) = epsilon_{infinity}+ delta-epsilon/(1 + j*omega*tau)

where epsilon(omega) is the permittivity at omega angular frequency, epsilon_{infinity}is the limit of permittivity at high frequency (omega*tau >>1), tau is the time it takes to polarize the dielectric, delta-epsilon = epsilon_{s}- epsilon_{infinity}(where epsilon_{s}is the permittivity at omega*tau<< 1), a measure of a permittivity dispersion region that is driven by tau (different factors drive tau at different frequency ranges, q.v., e.g., http://en.wikipedia.org/wiki/Complex_permittivity#Complex_permittivity), and j = -1^{1/2}.

How do I put frequency values in for omega, such as in what units, and crank it to get permittivity at a given frequency out? General comments on using complex frequency are welcome, too.

Thanks (and hopefully in my first post I described the problem so it's not gibberish :-).

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# How to compute complex relative permittivity

Can you offer guidance or do you also need help?

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