Photofragmentation of CH3Cl+ at 366 nm

Abstract

The photofragmentation of methyl chloride cation was examined at a wavelength of 366 nm, using the anisotropy associated with the trapping efficiency of an ion cyclotron resonance spectrometer. The direction of the transition dipole moment as determined from the angular distribution of the CH⁺₃ photofragments is parallel to the carbon–chlorine bond. This was interpreted as supporting the contention that the optical transition involved in the dissociation process is ²E←²E. The average kinetic energy of the CH⁺₃ fragment was estimated to be 0.58 eV, indicating that some of the excess energy remaining after dissociation is partitioned into the internal modes of the methyl cation fragment.