Effect of charge transfer interaction and disorderness on transport properties of polyaniline systems

Films of pure polyaniline and polyaniline-tetracyanoquinodinodimethane have been prepared. The optical absorption spectra of both the samples in the emeraldine base forms are explained in light of the three-dimensional exciton model. A temperature dependence study of the electrical conductivity of the samples shows an interesting crossover phenomenon ${\mathrm{(T}}_c\text{=143}$ K) which may be considered as competition of the two opposingly directed factors, namely, charge transfer interaction and the disorderness parameter $\mathrm{(r).}$ While charge transfer interaction is evident from optical absorption spectroscopy, the extent of disorderness is reflected by the results of CHN microanalysis and temperature dependent electrical conductivity measurement.