Photodissociation of isobutene at 193 nm

Abstract

The collisionless photodissociation dynamics of isobutene (i-C 4 H 8 ) at 193 nm via photofragment translational spectroscopy are reported. Two major photodissociation channels were identified: H + C 4 H 7 and CH 3 + CH 3 CCH 2 . Translational energy distributions indicate that both channels result from statistical decay on the ground state surface. Although the CH 3 loss channel lies 13 kcal mol À1 higher in energy, the CH 3 : H branching ratio was found to be 1.7 (5), in reasonable agreement with RRKM calculations.