Theoretical study of perfluorinated oligothiophenes: electronic and structural properties

A quantum-chemical study at the Hartree-Fock, (HF), second order Moeller-Plesset perturbation theory, (MP2), and density functional theory, (DFT), levels was performed on perfluorinated oligothiophenes with the aim to predict the potential utility of these materials in the development of electronic devices based on organic n-type semiconductors. The electronic properties analyzed, such as ionization potential, HOMO-LUMO energy difference and electron affinities suggest that perfluorinated oligothiophenes are more difficult to oxidize, and have a larger band gap in comparison with their non-substituted parent compounds. Structural changes on bond lengths and bond angles between perfluorinated and non-substituted oligothiophenes were also observed. Thus, the incorporation of fluorine atoms into oligomers structure could be an effective way to design materials with n-type conductivity. (C) 2004 Elsevier Ltd. All rights reserved.