Cole–Cole equation

The Cole–Cole equation is a relaxation model that is often used to describe dielectric relaxation in polymers.

It is given by the equation

where ${\displaystyle \varepsilon ^{*}}$ is the complex dielectric constant, ${\displaystyle \varepsilon _{s}}$ and ${\displaystyle \varepsilon _{\infty }}$ are the "static" and "infinite frequency" dielectric constants, ${\displaystyle \omega }$ is the angular frequency and ${\displaystyle \tau }$ is a time constant.

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