Detalle de: Singlet fission in pentacene dimers

Significance In the present work, we show compelling evidence for the unprecedented intramolecular singlet fission at room temperature and in dilute solutions within a set of three different regioisomeric pentacene dimers. Pump–probe experiments, which were complemented by theoretical calculations using high-level ab initio multireference perturbation theory methods, corroborate triplet quantum yields as high as 156 ± 5%. To this end, electronic couplings between the two pentacenes in the dimers, by virtue of through-bond or through-space interactions, are decisive in tuning the rates of singlet fission.