A chaotic approach to the interpretation of redox processes in conducting polymers

Charge transfer in conducting polymers involves an insulator/conductor transition produced by the oxidation state change of the film. The accumulation, of positive charges in the films is compensated by cation expulsion and/or anion incorporation. This implies the diffusion/migration of ions and electrons inside the film and the exchange of solvent with the electrolyte. These phenomena are characteristically nonlinear, dissipative processes which must also be strongly influenced by feedback. Nonlinearity, dissipation and feedback in a dynamical system are clearly contained in a quadratic logistic equation. Thus, it is of much interest to show that this equation can describe the flow of ions and associated phenomena, like changes in absorbance, in a film promoted by a potential scan into the active region.