Supramolecular electronic coupling in chiral oligothiophene nanostructures

The effects of supramolecular assembly on the photoluminescence (PL) decay rates of oligothiophenes nanostructures was investigated. A series of three functionalized oligothiophenes were investigated, using time-integrated and time-resolved PL spectroscopy, that were shown to self-assemble into chiral supramolecular stacks in semipolar solvents. The functionalized oligothiophenes are model systems for investigating intermolecular electronic coupling effects because the supramolecular assembly process in solution is thermotropically reversible with a well-defined transition temperature. The supramolecular organization of a series of functionalized oligothiophenes led to a strong intermolecular interactions and all spectral features agreed with an H-aggregate arrangement. The degree of electronic interactions were found to decrease with increasing size of the oligomer.