One-dimensional localization effects in three-dimensional structures of highly-conducting polymers

Starting with a model of weakly overlapping metallic chains we developed a transport theory for degenerate electrons in an irregular structure of fibril-form polymers. The anisotropy of intrafibril kinetic characteristics is enhanced by highly anisotropic scattering by dopants. Therefore, in spite of the weak backward impurity scattering, the 1d localization effects can be profound on an intrinsic level. The kinetic state of the 3d polymer structure is determined by the interfibril electron transfer-rate and the density of cross-links. The role of phonons consists mainly in breaking of localization at higher temperatures. In the dielectric phase at low temperatures the transport is provided by phonon-assisted hopping. The interplay between weak interfibril hopping and fast intrafibril incoherent diffusion leads to the specific temperature dependence for the conductivity and the dielectric properties. These results describe very well the experimental dependencies for dc-conductivity and mw-dielectric constant in heavily doped polyacetylene and polyaniline.