1 April 1992 Photodissociation dynamics of ethylene sulfide and allene at 193 nm studied by time-of-flight mass spectroscopy
Author Affiliations +
Photodissociation dynamics of ethylene sulfide (C2H4S, thiirane) and allene (C3H4) at 193 nm is studied by time-of-flight (TOF) photofragment mass spectroscopy. In the photodissociation of C2H4S, the two fragments, S and SH, from two dissociation processes, C2H4S + hv yields S(1D) + C2H4 (1) and yields SH + C2H3 (2), were detected. Translational energy distributions of the S(1D) fragment from reaction (1) exhibit two components, a low and a high energy component, indicating the contribution of two different dissociation channels; a direct dissociation and a long-lived near-statistical dissociation producing a vibrationally excited counter fragment C2H4. This interpretation was confirmed by the observed center-of- mass (CM) angular distributions which exhibit two S(1D) components with different lifetimes. Translational energy and CM angular distributions of SH from reaction (2) are found to indicate that the excited molecule is long-lived and near-statistical, and is consistent with the dissociation process of CH2-CH-SH intermediate formed after ring opening and subsequent 1,2-hydrogen migration. The energy flow in the excited ethylene sulfide by 193 nm photon impact which results in forming S atom and SH fragments is discussed. Photodissociation dynamics of allene (C3H4) has also been studied using the same technique. The primary dissociation product channel detected at m/e equals 39 is C3H3 + H and the minor channel C3H2 + H2 has also been detected at mass m/e equals 38.
© (1992) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Kiyohiko Tabayashi, Kiyohiko Tabayashi, Kosuke Shobatake, Kosuke Shobatake, "Photodissociation dynamics of ethylene sulfide and allene at 193 nm studied by time-of-flight mass spectroscopy", Proc. SPIE 1638, Optical Methods for Time- and State-Resolved Chemistry, (1 April 1992); doi: 10.1117/12.58137; https://doi.org/10.1117/12.58137

Back to Top