Havriliak-Negami relaxation
- 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 polymersfn|1, by adding two exponential parameters to the Debye equation:
:
where is the permittivity at the high frequency limit, where is the static, low frequency permittivity, and is the characteristic relaxation time of the medium. The exponents and describe the asymmetry and broadness of the corresponding spectra.
Notes
* 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
* Debye relaxation
* Dielectric relaxation
* Dielectric spectroscopy
* Dipole
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