Rotational Effects on the Channel Three Decay in Benzene: in Support of the Preisomerization Mechanism.

The "Channel 3" phenomena in benzene were investigated concerning a model scheme as an extension of that applied for a typical intermediate case molecule, pyrazine. Using a multiple doorway-states formalism, the difficulties in interpreting such as insufficient density of states for the intermediate dark levels were eliminated based on a preisomerization diagram involving a benzene isomer, most probably benzvalene. By a detailed examination of information about the title subject in the literature concerning both experiments and theory, several questions were raised and answered while making proposals for further study.