Density Functional Theory Study of Electroactive Materials Based on Thiophene in Their Neutral and Doped States

Oligothiophenes provide interesting models for understanding the structural and electronic peculiarities which control the charge transport and optical properties in polythiophene. We have theoretically studied the effect of doping in oligothiophenes (nT, n=2-8) with the DFT method at UB3LYP level with 6-31G (d) basis set. Our attention was focused on the study of the geometrical and electronic properties in the neutral and doped states. We showed that the doping process modify both bond lengths and torsion angles as well as electronic properties by enhancing the planarity and reduction of the band Gap.