Conductivity and thermoelectric power of the newly processed polyacetylene

Abstract

Temperature dependent electrical conductivity and thermoelectric power are measured for the newly processed polyacetylene film doped with transition metal halides. Results of both four-probe and Montgomery methods for the dc conductivity measurement are presented. The four-probe results are somewhat anomalous. At present, the Montgomery measurement results show the maximum conductivit, δ max = 30,000 S/cm at T = 220K in the FeCl 3 deped stretch-oriented-polyacetylene. Quasi-linear temperature dependent thermoelectric power are observed for the samples indicating that the doped polyacetylenes are metallic. Although high anisotropies are observed in electrical conductivity for these samples, the thermoelectric power data are isotropic, which suggest that the fibrillar orientation is not perfect in one direction. The possibility of Kondo-effect like couplings in these samples are discussed.