PHOTODISSOCIATION DYNAMICS OF THE METHYL RADICAL 3S RYDBERG STATE

The photodissociation dynamics of methyl radical have been investigated at 193.3 nm using photofragment translational spectroscopy. The formation of CH2 and H(2S) was the only dissociation pathway observed. Although it is not possible to assign the spin state of the methylene unambiguously, we believe that methylene is produced predominately in the ã 1A1 excited state. The translational energy distribution of the products is peaked at ∼13 kcal/mole which is consistent with the magnitude of the exit barrier on the excited state potential energy surface. The breadth of the distribution suggests that the methyl radicals dissociate from a wide range of geometries. From the photofragment angular distribution an anisotropy parameter of β=-0.9±0.1 was determined. © 1995 American Institute of Physics.