Influence of Oxygen on the Transfer Efficiency and Fluorescent Yield of Organic Solutions

The quenching action of oxygen on the transfer efficiency and fluorescent yield of organic solutions is investigated in systems in which the transferring solvent is undiluted and in systems in which it is diluted by an inert solvent. It is shown that quenching by oxygen is a process competing with energy transfer from the solvent to the solute, with emission of solute fluorescence, and with self‐quenching of the solute. Experimental evidence for the assumption that transfer of energy takes place by a direct interaction between excited solvent molecules and accepting solute molecules is augmented.