Low temperature transport properties of Cl-doped conducting polyaniline

A study on the electron transport property based an the measurement of the electrical conductivity of HCl doped conducting polyaniline both in the presence as well as in absence of magnetic field has been made in the temperature range of 1.8 K less than or equal to T less than or equal to 300 K. The conductivity of the samples has been observed to show an increasing trend with increasing temperature. The conductivity ratio [r = sigma (300 K)/sigma (1.8 K)] is large for the sample having higher dopant concentration. A transition from Mott (T-1/4) to Efros-Shklovskii (ES) (T-1/2) in the temperature dependent conductivity has been observed at 10 K. The electrical conductivity obeys T-3/4 law in presence of magnetic field. Such parameters as density of states, molecular vibrational frequency, hopping distance and localization length have been determined from the plot of conductivity versus temperature. (C) 2001 Elsevier Science Ltd. All rights reserved.