Cooperative charge transport

Electroactive donors, such as TTF or triarylpyrazoline, can be bound in high yield to polymeric matrices. The TTF linear polymers show interesting cooperative properties (i.e., ion-radical cluster formation) that is not observed for the isolated monomers in solution or the low coverage polymers. Furthermore, thin solid films of these donors bound to cross-linked polymer backbones display remarkably facile charge transport through the film bulk which is accompanied by dramatic and reversible optical changes. 

Cooper pairs which are formed by two electrons.) Although the -> conductivity of the electronically conducting phase is a critical factor in all electrochemical experiments and applications, electrochemists are mostly interested in the ionic charge transport in electrolyte solutions or surface layers [i-iii]. Mixed, electronic and ionic conductivity occurs, e.g., in polymer-modified electrodes [ix], and in many -> solid electrolytes (see also... 

Hereby, B, A and Tq are material-dependent parameters. The parameter is proportional to the activation energy of ionic transport. In a system with a strict coupling between dynamic viscosity and conductivity, as described by the Stokes-Einstein equation, the parameter B in (8.8) is equal to the parameter B in (8.10). In a system with a higher probability for the motion of ionic charge carriers than for viscous flow events, as it can be found in case of cooperative proton transport mechanisms, the strict coupling between dynamic viscosity and conductivity does not hold [56-58]. In this case the parameter Bg in (8.10) will be smaller than B in (8.8). Combining (8.8) and (8.10) and considering the concentration dependence of cr, by introduction of the molar conductivity one will yield a fractional Walden rule (-product) as shown in (8.11). 

When we deal with the real polymer systems, disorder effects have to be taken into consideration. This is because in the (quasi) one-dimensional system the disorder tends to make the electronic states localized in cooperation with the electron-lattice coupling [12]. If the disorder is severe, the charges will be transported via hopping among the localized states accompanied by disorder potential as in the case of classical amorphous or non-crystalline media. This will be discussed in sections 2.3.2 and 2.3.3 in relation to the charge transport and recombination in the materials. 

For percolating microemulsions, the second and the third types of relaxation processes characterize the collective dynamics in the system and are of a cooperative nature. The dynamics of the second type may be associated with the transfer of an excitation caused by the transport of electrical charges within the clusters in the percolation region. The relaxation processes of the third type are caused by rearrangements of the clusters and are associated with various types of droplet and cluster motions, such as translations, rotations, collisions, fusion, and fission [113,143]. 

The authors are glad to thank many scientists, who have contributed to the results. The TEXTOR team, where the measurements were performed and highly reproducible plasmas were provided, especially to Dr. W. Biel, who did the experiments on the transport properties of TEXTOR, Prof. L. Vainshtein, Dr. A. Urnov and F. Goryaev provided us with the results of atomic data calculation. Dr. N. Badnell trained one of us (O. M.) to get the results on dielectronic recombination using atomic codes. Dr. S. Fritzsche put our attention to the cascades within the Li-like ions and Prof. R. Janev discussed the charge exchange recombination processes. Princeton Plasma Physics Laboratory supported the measurements on TEXTOR, both by cooperation with Dr. M. Bitter, and loan of X-ray detectors. 

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