| Abstract: | The mechanisms of chemical dedoping of conductive polypyrrole with the initial conductivity values differing by an order of magnitude have been studied using EPR spectroscopy. An analysis of the temperature dependences of the electrical resistance of the initial highly conductive samples and dedoped samples has revealed a transition from three-dimensional conduction in the initial samples to one-dimensional conduction in the dedoped samples. This transition is caused by the transformation of transverse bipolarons into longitudinal bipolarons and ipolarons. It has been established that transverse and longitudinal quasiparticles are stabilized by counterions involving iron ions in different spin states: the spin of iron in the counterion of a transverse bipolaron is 2 and iron is inactive in the EPR spectrum, whereas in the counterion of longitudinal quasiparticles, the spin of iron is 5/2 and iron becomes paramagnetic. |
