Spectral Research into Intramolecular Photoinduced Electron Transfer of Porphyrin-Anthraquinone Hybrids

Abstract

A series of covalently linked porphyrin (Por)-anthraquinone (AQ) hybrids Por-Cn-AQ (n=1, 4, 10) with flexible different length carbon chains were synthesized and their intramolecular photoinduced electron transfer (PET) properties were investigated mainly by steady-state fluorescence and decayed luminescence spectra. We studied the PET mechanism using density functional theory (DFT). We found that PET occurs from the porphyrin moiety to the anthraquinone moiety of these dyads and that the PET efficiency is influenced considerably by the length of the linkage between the two moieties in the hybrids. From both the experimental and theoretical results, we can conclude that the PET of these dyads is seemingly most compatible with a"through-bond"(super-exchange) mechanism.