The Effect of Counterions on the Interactions of Charged Oligothiophenes.

N. E. SINGH-MILLER, D. A. SCHERLIS, N. MARZARI.

JOURNAL OF PHYSICAL CHEMISTRY B - (Print)

AMER CHEMICAL SOC

Año: 2006 vol. 110 p. 24822 - 24826

1520-6106

The functionality of conjugated polymer systems often relies on oxidations or reductions, in most cases mediatedby the presence of counterions. The effect that the common counterion hexafluorophosphate (PF6-) has onthe intermolecular interactions between charged oligothiophenes is investigated here using ab initio quantumchemistry methods. Counterions are explicitly included in the simulations of oxidized oligothiophenes and inthe dimerization process. Our calculations provide quantitative and qualitative insight into the intermolecularinteractions in oligothiophene-counterion systems and show that the intermolecular ð-stacking of oligothiophenesis not adversely affected by the presence of counterions and that in fact oligothiophene dimerizationis further stabilized by their presence.