Aspects of Take Temperature Dependence of Electrical Conductivity in Polymeric Materials

The temperature dependence of the electrical conductivity of a number of polymeric organic and inorganic materials is described by a function, G(E,T), that is the derivative of the Fermi function. The mathematical justification for the use of this function in place of the Fermi function is described. Use of the G(E,T) function in the appropriate conductivity equation allows one to reproduce the temperature dependence of electrical conductivity in materials as diverse as (SN) and germanium single crystals, The function is found to be applicable to experimental conductivity data that collectively span a range of about 20 orders of magnitude, and a total temperature range of approximately 1000 K for the materials cited. The G(E,T) function adequately simulates the commensurate-incommensurate transition that is observed in materials such as (TMTSF)₂PF₆ and TTF-TCNQ. The importance of lattice order and the degree of single crystal perfection on derived properties of the conductivity curve are discussed. The G(E,T) function is applicable to other electron transport properties. The temperature dependence of electrical capacitance of SrTiO₃ is cited as an example,