Photodissociation of Iso-Propoxy (I-C3H7O) Radical at 248 Nm

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 using 248 nm (5.0 eV). The dominant product channels are CH₃ + CH₃CHO and OH + C₃H₆ with some contribution from H + C₃H₆O. CH₃ and H loss are attributed to dissociation on the ground electronic state of i-C₃H₇O, but in a nonstatistical manner because 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. These results corroborate what has been observed previously in C₂H₅O dissociation at 5.2 eV that yields CH₃, H, and OH loss. 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.