Dynamics of electronic energy transfer from the S2 state of azulene to the S2 state of zinc porphyrin

Abstract

Electronic energy transfer between the S₂ state of azulene as donor and the S₂ state of zinc porphyrin as acceptor in dichloromethane and CTAB micelles has been investigated. In dichloromethane high S₂–S₂ energy transfer efficiency, which cannot be explained using the Förster theory, is observed. An inhomogeneous distribution of acceptors surrounding the donor, leading to short-range exchange interaction and higher multipole interaction is proposed. In CTAB micelles, Förster's mechanism is found to agree well with the observed energy transfer efficiency when a surface-uniform distance distribution between donor and acceptor is assumed. The implications of S₂–S₂ energy transfer in our system for designing efficient molecular devices is discussed.