THE PHOTOACOUSTIC CALORIMETRY OF PHOTOSEN SITIZED REACTIONS INDUCED BY SINGLET OXYGEN

Pulsed photoacoustic spectroscopy has been used for the determination of quantum yields of singlet oxygen ((1) Delta(g)) production and for the measurement of type II photosensitized reactions. The thermodynami c and kinetic analysis of the photoacoustic signal generation demonstr ates the importance of the lifetime of the excited state in the measur ement of these parameters and opens the way to an experimental methodo logy. First measurements bf quantum yields of singlet oxygen have been obtained for various sensitizers in methyl alcohol. The possibility o f measuring the yield and energy of photo-oxygenation in solutions and more complex media is considered.