RENORMALIZATION APPROACH FOR TRANSPORT AND ELECTRONIC-PROPERTIES OF CONDUCTING POLYMERS

By means of the renormalization approach, we have developed a map that allows us to investigate transport and electronic properties in polya niline chains in terms of an effective lattice. This lattice may conta in impurities of two kinds: the first has the form of a couple of site s (dimer) with the same or different site energies according to the sy mmetry of the rings of the polymer it simulates; the other can occur w ithout constraint in the number of sites involved. In the case of more sophisticated descriptions of the polymer, the dimer model can be ina dequate and impurities of four sites have to be introduced in the map. We compare the results for the scattering properties of a single impu rity with those of a finite sample of the chain, and we show the depen dence of the results on the energies assigned to the carbon and nitrog en atoms of the polymer.