Temperature dependence of conductivity

If the temperature dependence of conductivity is known in a given solvent, an estimate of an unknown A0 at higher temperatures may be obtained which is much better than that measurable at lower temperatures with the help of the Walden rule ... 

Barthel, J. Temperature Dependence of Conductance of Electrolytes in Nonaqueous Solutions 13... 

FIGURE 25.8 Temperature dependence of conductivity for typical silver ion conductors, Agl and RbAg4l5, compared with those for YSZ and an aqueous solution of H2SO4. (From Gelings and Bouwmeester, 1997, Fig. 6.5, with permission from CRC Press LLC via CCC.)... 

Some transition metal complexes are excellent conductors. Thin films of cyto-chrome-C3, which contains four heme moieties coordinated by protein, exhibited a high conductivity with mixed valence state (Fe /Fe ) and showed an increase in conductivity as the temperature was decreased (2 x 10 S cm at 268 K) [68-70]. The temperature dependence of conductivity in the highly conductive region is the opposite of that of semiconductors and may preclude the ionic conduction as a dominant contribution. However, since the high conductivity is realized in the presence of hydrogenase and hydrogen, the system is not strictly a single but rather a multicomponent molecular solid. 

Figure 6.42 Temperature dependence of conductivity for various PEO-based polymer electrolytes containing divalent cations. Reprinted, by permission, from L. V. Interrante, L. A. Casper, and A. B. Ellis, eds.. Materials Chemistry, p. 110. Copyright 1995 by the American Chemical Society.

Flo. 9. Temperature dependence of conductivity of semiconductor pellets with and without added 10% wt of silver powder. The logarithm of structure-independent conductivity is plotted as a function of the reciprocal absolute temperature (degrees Celsius on top of the figure). Full lines are measured, dotted parts extrapolated (79). (Copyright by the Universite de Liege. Reprinted with permission.)... 

How does the granular metal conductivity depend on composition What is the difference between the temperature dependencies of conductivity for v>v c and x[Pg.633]

Thus it follows that the temperature dependence of conductivity is similar to that for band conduction (Eq. (2.37)), but for different reasons. 

The temperature dependence of conductivity chain axis [14]. Although oj /charge transport, is nearly identical in both cases (oj and interchain transport plays the limiting role in bulk charge transport properties. 

Nevertheless, there are cases in which conductivity is not governed by disorder, or at least in a less drastic way. This is the case of highly conducting polyacetylene [27]. Conductivity approaching the value of copper at room temperature has been reported, and a high value is still observed at low temperature. Recently, polyaniline with camphor sulfonic add (CSA) as the counterion has been reported to present an almost flat temperature dependence of conductivity [28]. Such examples are quite rare, but they are of major importance for an understanding of the intrinsic conduction process. 

In most CPs the temperature dependence of conductivity has behavior resembling Mott s VRH law, that is,... 

Tens of conductive LB films have been developed so far, including metallic and superconductive LB films. These LB films are classified into the categories anion radical salt, charge-transfer complex, cation radical salt, conducting polymer, and transition metal complex in this section. The LB films, with metallic temperature dependences of conductivity, and the fullerene LB films, which exhibit a superconducting transition, are discussed separately. 

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