Ultrafast photochemistry with two product channels: Wavepacket motion through two distinct conical intersections
Chemical Physics Letters 683 (2017) 128–134
Light induced bond cleavage is an ubiquitous process in large molecules, yet its quantum nature is not fully understood. We present a comprehensive description of the ultrafast light induced CACl bond cleavage in diarylmethyl chlorides combining femtosecond transient absorption measurements with ab initio calculations. We observe a delayed appearance of radicals (80 fs) and cations (125 fs). The excited state wavepacket moves initially toward two conical intersections and the passing through these intersections determines the partitioning into the differing product channels. Different locations of the conical intersections explain the observed delay times.