Low-frequency electrical conductivity of poly(phenylacetylene)-iodine in tetrahydrofuran solutions: effect of iodine concentration

The electrical conductivity of poly(phenylacetylene)-iodine in tetrahydrofuran solution has been measured at the frequency of 10 kHz, in the temperature range from −15 to 40 °C as a function of iodine concentration. The data have been analysed on the basis of the counterion fluctuation model developed for highly charged polyelectrolyte aqueous solutions. The dependence of the electrical conductivity on the iodine concentration suggests that the conduction mechanism is governed by the interaction of the polymer with iodine molecules, resulting in a charge-transfer complex in solution, the effectiveness of which is maximum at some well-defined concentrations corresponding to six polymer units for each I5− ion.