Nanostructured Organic Thin Films: Electronic Energetics and Devices

We report on the optoelectronic properties of vacuum sublimed organic thin films of the oligothienyls (Tn) model systems. The Davydov splitting (DS) of the lowest exciton is about 0.3 eV and decreases with the conjugation length when going from T 4 to T 6. The lowest DS component is partially forbidden due to the crystal packing and the spectral activity occurs via Herzberg-Teller (HT) vibronic coupling. We show the real time dynamics of the HT coupling by coherent vibrational spectroscopy and the role of aggregates in the energy ...