(Taylor & Francis Ltd, 2003) Department of Chemistry; N/A; Yurtsever, İsmail Ersin; Kırmızıaltın, Serdal; Faculty Member; Undergraduate Student; Department of Chemistry; College of Sciences; College of Sciences; N/A; N/A
Vibrational spectra of oligothiophenes with structural defects are calculated within the density-functional-theory methodology. The effects of the defective ab linkages on the infrared (IR) and Raman spectra are characterized from calculations of all isomers up to the hexamer. The signatures of ab linked monomers can be found in IR spectra from broken symmetry arguments which result in absorptions localized in the defective region. The positions of the absorption peaks in the Raman spectra seem to be unaffected by the presence of such defects; however, strong reductions in the intensities are observed because of the shortening of the conjugation length.
