Delocalization length, electronic properties and vibrational spectra of neutral α,α′ -dimethyl end-capped oligothiophenes

We present FT-Raman and FT-IR spectra of neutral α,α′-dimethyl end-capped oligothiophenes (to six thiophene units) as solid samples and in solution. Gas-phase potential to internal rotation of α,α′-dimethylbithiophene has been predicted by ab initio calculations at the RHF/ 6-31G** level, as a model for the theoretical study of the conformational flexibility of these molecules.