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Havriliak-Negami relaxation

Havriliak-Negami relaxation is an empirical modification of the Debye relaxation model, accounting for the asymmetry and broadness of the dielectric dispersion curve. The model was first used to describe the dielectric relaxation of some polymers1, by adding two exponential parameters to the Debye equation:

\hat{\varepsilon}(\omega) = \varepsilon_{\infty} + \frac{\Delta\varepsilon}{(1+(i\omega\tau)^{\alpha})^{\beta}},

where \varepsilon_{\infty} is the permittivity at the high frequency limit, \Delta\varepsilon = \varepsilon_{s}-\varepsilon_{\infty} where \varepsilon_{s} is the static, low frequency permittivity, and τ is the characteristic relaxation time of the medium. The exponents α and β describe the asymmetry and broadness of the corresponding spectra.


  • Note 1: Havriliak, S. and Negami, S., A complex plane representation of dielectric and mechanical relaxation processes in some polymers, Polymer 8 (4), pg. 161, 1967

See also

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Havriliak-Negami_relaxation". A list of authors is available in Wikipedia.
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