Mechanism for intramolecular proton transfer involving hypericin

This paper pertains to the characterization of the transient species arising from intramolecular proton transfer involving hypericin. In this regard, a calculation showed that the dipole moment for the transition state associated with proton transfer was 11.63 D, which was much higher than the value (3.49 D) for the ground state. This suggests that a charge separation process such as proton dissociation or electron transfer is involved in the formation of the transient species.