Direct and alternate current conductivity and magnetoconductivity of oxalic acid doped polyaniline

The results on the measurement of conductivity of oxalic acid doped polyaniline in the temperature range 77≤T≤300K, applying magnetic field up to 1 T in the frequency range 20–1 MHz are being reported. The dc conductivity has been interpreted by variable range hopping theory. The magnetoconductivity is positive, which is well explained by orbital magnetoconductivity theory. The frequency dependence of conductivity has been described by power law and the frequency exponent ‘ss’ is found to be decreasing with temperature. The dielectric permittivity is large, which has been interpreted by the grain and grain boundary effect. Magnetic field dependence ac conductivity shows a positive variation. A firm theoretical explanation of magnetic field dependence of ac conductivity is still lacking. The different parameters like Mott characteristic temperature and localization length were calculated from the experimental data, the values of these parameters depend strongly on the resistivity ratio.