Thermopower and conductivity of metallic polyaniline

Abstract The temperature dependences of conductivity and thermopower of the metallic polyaniline salts are presented, along with the dependence of conductivity on chemical potential and doping level. As the degree of protonation increases, the sign of the thermopower changes from positive to negative. Although the structure of the polyaniline is known to be complex, we propose a model which can interpret the thermopower sign-cross-over behavior in a relatively simple way.