Ultrafast photochemistry in OClO molecules analyzed by femtosecond time-resolved photoelectron spectroscopy Original Research Article

Applying the coincident detection of photoions and photoelectrons with femtosecond time resolution we have analyzed the energetics and the dynamics of the ultrafast processes initiated by excitation of OClO molecules with 50 fs laser pulses at 398 nm. The major channel leading to the excitation of the à 2A2 electronic state is characterized by spin–orbit coupling to the 2A1 electronic state within 7 ps, the subsequent transition to the 2B2 state within 250 fs and, finally, the fragmentation to ClO+O and Cl+O2 within about 750 fs. A minor channel is tentatively assigned to the direct excitation of the 2A1 state.