Transfer of Electronic Excitation Energy in Solid Solutions of Perylene in N-Isopropylcarbazole

Abstract

The electronic excitation energy transfer from the host material to guest molecules has been studied in the system perylene/N-isopropyl carbazole by measuring the fluorescence intensity ratio guest/host over a great range of guest concentrations. Exciton diffusion and single-step transfer are discussed as possible transfer mechanisms; it is shown that the former process prevails in this system. According to the hopping model, the number of steps during the lifetime of the exciton is calculated to be 4 × 104, and the average displacement from the starting point amounts to 1350 Å.