Triplet-exciton generation mechanism in a new soluble (red-phase) polydiacetylene - art. no. 187402

The time scale of covalent state relaxation and singlet fission into triple t pairs is determined in a solution of-isolated polydiacetylene chains show ing a remarkably sharp excitonic transition by applying the transient trans mission difference spectroscopy technique with sub-10 fs optical pulses. Ph otoexcitation into, the band of ionic states is followed by a branching wit hin the first 100 fs which populates the band of covalent states. The latte r start. to dissociate into triplet excitations, completing the process in about 300 fs.