PHOTODISSOCIATIVE PATHWAYS OF C2H2 AT 121.6 NM REVEALED BY A DOPPLER-SELECTED TIME-OF-FLIGHT (A 3-D MAPPING) TECHNIQUE

The photodissociation dynamics of C2H2 near the H-atom Lyman-a transit ion was investigated by a newly developed, Doppler-selected time-of-fl ight technique. The aim of this study is to elucidate the detailed dyn amics via the directly measured fragment 3-D distribution. An alternat ive, preliminary analysis of a fraction of the data is presented here which already reveals a rich dynamics involved in the photodissociatio n. A strong propensity against the formation of the ground electronic CxH((X) over tilde 2 Sigma) state, a prominent C-H stretching excitati on in the production of the C2H((A) over tilde) state, and two distinc t dissociation pathways being likely involved in the title process hav e been found.