Inhomogeneously disordered

Figure 5 Schematic view of the inhomogeneous disorder in these doped poiymers, with individual polymer chains passing through both ordered regions (typically 3-10 nm across) and disordered regions (of length s ).

Inhomogeneous Disorder-Induced Insulator-Metal Transition Quantum Hopping in Metallic Polymers ... 

Inhomogeneous Disorder-Induced Insulator-Metal Transition... 

FIGURE 15.3 (a) Schematic picture of the inhomogeneously disordered state of metallic and insulating conducting... 

The dielectric function and optical conductivity provide insight into the nature of the disorder in the metallic state. In this section, s(a>) and ) for the PAN-CSA samples are compared with the localization-modified Drude model for homogeneously disordered systems and a model for inhomogeneous disorder. 

Epstein, A.J., et al. 1994. Inhomogeneous disorder and the modified drude state of conducting polymers. Synth Met 65 149. 

Induced circular dichroism (ICD), 9-16 Infrared active vibrations Theory, 22-5 Inherent one-dimensional (ID) nature, 16-2 Inherently nonhomogeneous character, 16-2 Inhomogeneous disorder model, 15-8, 15-10-15-14 comparison with experimental results... 

Inhomogeneous Disorder Stmctural configuration for a polymer solid which consists of a mixture of ordered (crystalline) and disordered regions of the polymer. 

In contrast, if the disorder is inhomogeneous with large variations on the length scale of or larger than the characteristic electron localization lengths, then the behavior expected for a composite system may be expected. The inhomogeneous disorder model... 

To determine the nature of the metallic state in conducting polymers, it is necessary to use a wide variety of probes. Direct current transport measurements provide insight into the insulating or metallic nature of electrons at the Fermi level. Measurement of high frequency transport provides an important probe away from the Fermi energy to help discriminate between the homogeneously and inhomogeneously disordered metallic states... 

Fig. 3.4 (a) Schematic picture of the temperature dependence of the various scattering times in the inhomogeneous disorder model and the respective localization domains, (b) The corresponding diffusion constant expected for the inhomogeneous quasi-one-dimensional system. (From Ref. 87.)... 

For a truly metallic system, the dc conductivity will remain finite as 0 [65] and the logarithmic derivative of the conductivity (W = d n positive slope at low T[76]. In contrast, for an unpercolated system, the dc conductivity will decrease rapidly at low T and the W plot will have a negative slope, characteristic of hopping systems. In the inhomogeneous disorder model, the W plot will show a crossover in the low T slope for the W plot from negative to positive, though the IMT is not necessarily a monotonic function... 

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