Charge transport models

Nelson J, Kwiatkowski JJ, Kirkpatrick J, Frost JM (2009) Modeling charge transport in organic photovoltaic materials. Acc Chem Res 42 1768... 

The Poisson equation can also be used in modelling - charge transport phenomena in - semiconductors and -> conductive polymers [iv, v]. 

Modeling Charge Transport within the Conjugated Polymer Film... 

In this section we derive expressions for the rates of electron transfer within the Fermi Golden Rule approximation. As we described for exciton transport in Section 9.2.4, these rates can be used to model charge transport using the density matrix formalism. There is a wide and thorough discussion of this topic in May and Kiihn (2000). 

Applying some equatioo for the potential distribution as determined by probe technique together with the TSD method [130] and assuming a diffusion model charge transport, we obtained Eq. (17) analytically (131). 

One of the easiest ways to model charge transport in a random distribution of localized states is via Monte Carlo simulation [7, 8]. The essential input parameter is the width a of the DOS, which is usually assumed to be of Gaussian shape ... 

According to the Scher-MontroU model, the dispersive current transient (Fig. 5b) can be analyzed in a double-log plot of log(i) vs log(/). The slope should be —(1 — ct) for t < and —(1 + a) for t > with a sum of the two slopes equal to 2, as shown in Figure 5c. For many years the Scher-MontroU model has been the standard model to use in analyzing dispersive charge transport in polymers. 

The development of microelectronics cannot be envisaged without a comprehensive modeling of the devices. The modeling of OFETs is currently hampered by several features. First, charge transport in organic semiconductors is still not completely understood. The situation is clear at both ends of the scale. In high mobility materials (//>IOcnr V-1 s l), transport occurs within delocalized levels when temperature... 

There have been several other models presented over the last few years, which describe charge transport in LEDs based on soluble PPVs 85] and in Alq3 82). 

One has to consider that in Eqs. (9.15)—(9.17) the mobility /t occurs as a parameter. As it will be pointed out below, // shows a characteristic dependence on the applied electric field typical for the type of organic material and for its intrinsic charge transport mechanisms. For the hole mobility, //, Blom et al. obtained a similar log///,( ) const. [E dependency [88, 891 from their device modeling for dialkoxy PPV as it is often observed for organic semiconductors (see below). 

Charge transfer kinetics for electronically conducting polymer formation, 583 Charge transport in polymers, 567 Chemical breakdown model for passivity, 236... 

In particular, considering a ballistic model for the charge transport through a dot, it was possible to demonstrate that the current through it should be represented as a series of equidistant peaks whose positions correspond to the steps in the coulomb staircase. 

Moreover, as a consequence of their transient character, a hierarchy of clusters in dynamic equilibrium that may differ in shape and size can be hypothesized [253], Mass, momentum, and charge transport within a cluster of reversed micelles is expected to be strongly enhanced as compared to that among isolated reversed micelles. It has been shown that the dynamics of a network of interacting reversed micelles is successfully described by a model developed by Cates [35,69,254],... 

Fig. 1 The w-stack of double helical DNA. In this idealized model of B-DNA the stack of heterocyclic aromatic base pairs is distinctly visible within the sugar-phosphate backbone (schematized by ribbons) a view perpendicular to the helical axis b view down the helical axis. It is the stacking of aromatic DNA bases, approximately 3.4 A apart, that imparts the DNA with its unique ability to mediate charge transport. Base stacking interactions, and DNA charge transport, are exquisitely sensitive to the sequence-depen-dent structure and flexibility of DNA...

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