An organic solid supporting electronic charge transport; conjugation, intermolecular packing and disorder influence its properties.
Molecular excitations in organic semiconductors often retain strong local character. Weak screening supports Frenkel excitons or intermolecular charge-transfer admixtures, so a photon can create a bound neutral excitation rather than free carriers. Transition dipoles, spin selection rules, molecular packing and Franck-Condon factors set the bright spectral features. Disorder and thermal vibrations broaden them. Electronic overlap can also produce more delocalized excitons; the molecular limit is a useful model, not a definition covering every organic solid.
A soluble fullerene derivative, commonly the C60-based phenyl-C61-butyric acid methyl ester, used as an electron acceptor in organic photovoltaic blends. Different fullerene cage sizes give related derivatives.
A conjugated polymer with hexyl-substituted thiophene repeat units, often used as a model electron-donor semiconductor. Regioregularity and packing influence its optical and transport response.
Articles by others on the same topic
Organic semiconductors are materials that possess semiconductor properties and are primarily composed of carbon-based compounds. These materials can conduct electricity due to the presence of pi-conjugated systems, where electrons can move freely along the molecular chains.