Singlet oxygen-sensitized delayed emissions from hydrogen peroxide/gallic acid/potassium ferricyanide systems containing organic solvents

Fourier-transform chemiluminescence spectra of H2O2/gallic acid/K3[Fe(CN)6] systems containing organic solvents were measured. Emission bands with peaks around 530 and 700 nm were observed in systems containing solvents with a carbonyl group such as N,N-dimethylformamide, and those with a hydroxyl group such as methanol, respectively. The relative band intensities depended strongly on the concentration of these organic solvents. The emission species are attributed to gallic acid–ferricyanide complexes excited by energy transfer from singlet oxygen dimol, (1O2)2. The effects of organic solvents are interpreted in terms of intermolecular interactions of gallic acid–ferricyanide complexes, water molecules and organic solvents.