FT-Raman Studies of Charged Defects Created on Methyl End-Capped Oligothiophenes by Doping with NOBF4

Oligothiophenes have been investigated extensively as models of polythiophenes with defect-free chemical structures. Here the authors report on the FT-Raman spectra of α-methyl-substituted oligomers of thiophene (see Figure for the chemical structure) doped with NOBF4, a relatively strong acceptor. The Raman spectra of the second oxidized species for longer chain oligomers are found to closely reproduce the spectra of the charge carriers in doped polythiophene.