Quantum Chemical Analysis of Electronic Structure and N- and P-Type Charge Transport in Perfluoroarene-Modified Oligothiophene Semiconductors
Density-functional theory (DFT) is employed to investigate the structural, electronic, and transport properties of several isomeric fluoroarene-oligothiophene-based semiconductors. Three oligothiophene systems varying in the perfluoroarene group positions within the molecule are studied to understand the electronic structure leading to the observed mobility values and to the n- or p-type behavior in these structures. Analyses of both intermolecular interactions in dimers and extended interactions in crystalline structures afford considerable insight into the electronic properties and carrier mobilities of these materials, as well as the polarity of the charge carriers. From the calculated carrier effective masses, we find that sterically governed molecular planarity plays a crucial role in the transport properties of these semiconductors. Our calculations correlate well with experimentally obtained geometries, highest-occupied molecular orbital (HOMO)/lowest-unoccupied molecular orbital (LUMO) energies, and the experimental carrier mobility trends among the systems investigated.
S. E. Koh et al., "Quantum Chemical Analysis of Electronic Structure and N- and P-Type Charge Transport in Perfluoroarene-Modified Oligothiophene Semiconductors," Journal of Physical Chemistry B, American Chemical Society (ACS), Jan 2006.
The definitive version is available at http://dx.doi.org/10.1021/jp064840x
United States. Office of Naval Research
National Science Foundation (U.S.)
Keywords and Phrases
Oligothiophene Systems; Density-Functional Theory; Electronic structure
Article - Journal
© 2006 American Chemical Society (ACS), All rights reserved.