Investigation of exciton coupling in oligothiophenes by circular dichroism spectroscopy

The solid-state photophysical properties of semiconducting polymers result from the interplay between the intrinsic features of the polymer chains and interchain interactions. Exciton coupling, which in principle can be estimated from circular dichroism (CD) spectra, is one of the major interchain interactions affecting the optical properties of semiconducting polymers. Here the authors present a combined experimental and theoretical investigation of the chiroptical properties of oligothiophenes. The results confirm that the CD spectrum provides an independent estimate of the exciton coupling