Conwell

However, although it allowed a correct description of the current-voltage characteristics, this model presents several inconsistencies. The main one concerns the mechanism of trap-free transport. As noted by Wu and Conwell [1191, the MTR model assumes a transport in delocalized levels, which is at variance with the low trap-free mobility found in 6T and DH6T (0.04 cm2 V-1 s l). Next, the estimated concentrations of traps are rather high as compared to the total density of molecules in the materials (see Table 14-4). Finally, recent measurements on single ciystals [15, 80, 81] show that the trap-free mobility of 6T could be at least ten times higher than that given in Table 14-4. 

This almost distance independent hole transfer over (A T)n sequences where adenines are charge carriers is very surprising. Maybe the transfer of a positive charge between adenines of an (A T)n sequence is extremely fast, as recent calculations of M.D. Sevilla predicted [20], One could also speculate that the positive charge is delocalized over more than one A T base pair so that polaron hopping, which is discussed in this volume by G.B. Schuster as well as E.N. Conwell, might make the hole transport in oxidized (A T)n sequences very efficient. 

Ducatman AM, Conwell DE, Crawl J Germ cell tumors of the testicle among aircraft repairman, y Urol 136 834-836, 1986... 

E. M. Conwell, Introduction to Highly Conducting Quasi-One-Dimensional Organic Crystals... 

J. P. Pouquet, Structural Instabilities E. M. Conwell, Transport Properties C. S. Jacobsen, Optical Properties... 

Conwell, E. (1988). In Semiconductors and Semimetals Highly Conducting Quasi-One-Dimensional Organic Crystals, ed. E. Conwell, Vol. 27. Boston Academic Press. 

Gartstein YN, Conwell EM (1994) High-field hopping mobility of polarons in disordered molecular-solids - a Monte-Carlo study. Chem Phys Lett 217 41... 

The formation and transport properties of a large polaron in DNA are discussed in detail by Conwell in a separate chapter of this volume. Further information about the competition of quantum charge delocalization and their localization due to solvation forces can be found in Sect. 10.1. In Sect. 10.1 we also compare a theoretical description of localization/delocalization processes with an approach used to study large polaron formation. Here we focus on the theoretical framework appropriate for analysis of the influence of solvent polarization on charge transport. A convenient method to treat this effect is based on the combination of a tight-binding model for electronic motion and linear response theory for polarization of the water surroundings. To be more specific, let us consider a sequence... 

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