In this letter photoinduced interactions of methyl viologen (MV2+) with 9-aminoacridine hydrochloride hydrate (9AA-HCl) have been studied. In homogeneous medium, both photoinduced electron transfer (PET) and excited-state proton transfer (ESPT) are occurring whereas in micellar medium only PET is prevalent. Magnetic field effect confirms that the PET takes place primarily in the triplet state. Discrepancy in theoretically calculated and experimentally obtained B-1/2 values indicates the presence of electron hopping mechanism. Amalgamation of this letter with our previous report indicates that 9AA-HCl may either act as an electron donor or acceptor in PET reactions under suitable condition of redox potentials. (C) 2014 Elsevier B.V. All rights reserved.