Photodissociation of ethylene sulfide at 193 nm: A photofragment translational spectroscopy study with VUV synchrotron radiation and ab initio calculations

Photodissociation of ethylene sulfide at 193 nm has been studied using phot ofragment translational spectroscopy and ab initio theoretical calculations . Tunable synchrotron radiation was used as a universal;out selective probe of the reaction products to reveal new aspects of the photodissociation dy namics. The channel giving S + C2H4 was found to be dominated by production of;ground-state sulfur atoms (S(P-3):S(D-1) = 1.44:1), mostly through a sp in-forbidden process. The results also suggest the presence of a channel gi ving S(P-3) in conjunction with triplet ethylene C2H4 (B-3(tu)) and allow i nsight into the energy of the latter species near its equilibrium geometry, in which the two methylene groups occupy perpendicular planes, in addition , a channel leading to the production of HS with C2H2 also has been observe d. Our experimental results are supported and elaborated by theoretical cal culations.