UC Berkeley

Photodissociation of the i-C₃H₇O radical is investigated using fast beam photofragment translational spectroscopy. Neutral i-C₃H₇O radicals are produced through the photodetachment of a fast beam of i-C₃H₇O^- anions and are subsequently dissociated at 248 nm (5.0 eV). The dominant product channels are CH₃ + CH₃CHO and OH + C₃H₆ with some contribution from H + C₃H₆O. The CH₃ and H loss channels are attributed to dissociation on the ground electronic state of i-C₃H₇O, but in a nonstatistical manner because calculated RRKM dissociation rates exceed the rate of energy randomization. Translational energy and angular distributions for OH loss are consistent with ground state dissociation, but the branching ratio for this channel is considerably higher than predicted from RRKM rate calculations. Additionally, i-C₃H₇O undergoes three-body fragmentation to CH₃ + CH₃ + HCO and CH₃ + CH₄ + CO. These three-body channels are attributed to dissociation of i-C₃H₇O to CH₃ + CH₃CHO, followed by secondary dissociation of CH₃CHO on its ground electronic state.