Organic semiconductor electronic structures

Other types of carbon (amorphous or transitional forms with turbostratic structure) consist of fragments of graphitelike regions cross-linked to a three-dimensional polymer by carbon chains. Unlike graphite, the transitional forms are organic semiconductors with electrical properties determined by delocalized rr-electrons. 

C.J. Tonzola, M.M. Alam, W. Kaminsky, and S.A. Jenekhe, New //-type organic semiconductors synthesis, single crystal structures, cyclic voltammetry, photophysics, electron transport, and electroluminescence of a series of diphenylanthrazolines, J. Am. Chem. Soc., 125 13548-13558 (2003). 

Tanaka S, Kanai K, Kawahe E, Iwahashi T, Nishi T, Ouchi Y, Seki K (2005) Doping effect of tetrathianaphthacene molecule in organic semiconductors on their interfacial electronic structures studied by UV photoemission spectroscopy. Jpn J Appl Phys 44 3760... 

In conclusion, radiation chemical matrix isolation technique gives precise information on the electronic structure of charge carriers, which is useful for the molecular design of organic semiconductors as electronic and optical materials. 

Using physical organic chemical rationalizations, we were able to modify the electronic structure of a poly(heterocycle). The result was poly(isothianaphthene) a polymer which is already a semiconductor in the neutral (undoped) state. In the fully doped state, PITN is a transparent conducting polymer. 

As in the MD method, PES for KMC can be derived from first-principles methods or using empirical energy functionals described above. However, the KMC method requires the accurate evaluation of the PES not only near the local minima, but also for transition regions between them. The corresponding empirical potentials are called reactive, since they can be used to calculate parameters of chemical reactions. The development of reactive potentials is quite a difficult problem, since chemical reactions usually include the breaking or formation of new bonds and a reconfiguration of the electronic structure. At present, a few types of reactive empirical potentials can semi-quantitatively reproduce the results of first-principles calculations these are EAM and MEAM potentials for metals and bond-order potentials (Tersoff and Brenner) for covalent semiconductors and organics. 

This chapter summarizes some of our recent work in printing techniques and plastic electronics. It also presents new data from printed transistors that use several different organic semiconductors in a variety of device geometries. In all cases, we observed good performance. pCP for the source/drain electrodes is attractive because it provides a simple and potentially low-cost route to high resolution (i.e. small channel lengths, L) structures that can be used to build transistors which... 

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