Laser Spectroscopic Investigations on the Photoionization and Photosubstitution Reactions of 9-Phenylanthracene and Perylene

摘要

Photosubstitution reactions of aromatic compounds have been studied extensively by Havinga, Cornelisse and their co-workers. They found that electron transfer or charge transfer is an important step in the reaction mechanism. They have suggested that the electron ejection takes place from the lowest excited triplet state of the aromatic molecule. However, the intermediacy of singlet excited states was not ruled out. We have studied the photoionization and photosubstitution reactions of 9-phenylanthracene and perylene in polar solvents. Although solvent polarity is an important factor in the photoionization yield, we have observed that the ratio of positive and negative ions is determined by some microscopic solute-solvent interactions. Results indicate that the ionizing state is populated from the lowest singlet excited state of the aromatic molecule. (ERA citation 09:046318)