Dispersion and absorption in dielectrics: II. Direct current characteristics

  • Cole K
  • Cole R
  • 210


    Mendeley users who have this article in their library.
  • 333


    Citations of this article.


The dispersion and absorption of a considerable number of liquid and dielectrics are represented by the empirical formulaε*−ε∞=(ε0−ε∞)/[1+(iωτ0)1−α]. In this equation, ε* is the complex dielectric constant, ε0 and ε∞ are the ``static'' and ``infinite frequency'' dielectric constants, ω=2π times the frequency, and τ0 is a generalized relaxation time. The parameter α can assume values between 0 and 1, the former value giving the result of Debye for polar dielectrics. The expression (1) requires that the locus of the dielectric constant in the complex plane be a circular arc with end points on the axis of reals and center below this axis. If a distribution of relaxation times is assumed to account for Eq. (1), it is possible to calculate the necessary distribution function by the method of Fuoss and Kirkwood. It is, however, difficult to understand the physical significance of this formal result. If a dielectric satisfying Eq. (1) is represented by a three‐element electrical circuit, the mechanism responsible for the dispersion is equivalent to a complex impedance with a phase angle which is independent of the frequency. On this basis, the mechanism of interaction has the striking property that energy is conserved or ``stored'' in addition to being dissipated and that the ratio of the average energy stored to the energy dissipated per cycle is independent of the frequency.

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document


  • Kenneth S. Cole

  • Robert H. Cole

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free