H-atom scrambling and cis–trans isomerization of dideuteroethylene photosensitized by several organic compounds

Abstract

H-atom scrambling and cis–trans isomerization of dideuteroethylene have been observed with various photosensitizers: benzene, toluene, p-xylene, o-xylene, m-xylene, mesitylene, fluorobenzene, and benzotrifluoride. The pressure dependences are satisfactorily explained in terms of the two excited state mechanism previously proposed.Using Kassel's equation for the rate of unimolecular reactions, the energies of the triplet states of the sensitizers have been estimated. The values obtained coincide with the spectroscopic values.