Mechanism for the fluorescence quenching of dipyrenyl calix[4]arene upon complexation of Fe3+

Abstract

The investigations on fluorescence of dipyrenyl calix[4]arene in free state as well as of its Fe3+ complex have been carried out with changes in pH, temperature, solvent. The results show that dipyrenyl calix[4]arene exhibits monomer and excimer emissions depending on nature of solvent. Based on the way of fluorescence changes under different conditions, the fluorescence quenching of dipyrenyl calix[4]arene upon complexation of Fe³⁺ is attributed to the electron transfer from the excited pyrene to Fe³⁺ ion