Determination of formation constants at elevated temperatures by laser-induced photoacoustic spectroscopy

A photoacoustic spectrometer has been developed for high-sensitivity optical absorption measurements of aqueous solutions at temperatures from ambient to 90 C. The light source is a Nd:YAG-pumped dye laser, and the photoacoustic signal is detected with a piezoelectric transducer coupled to a thermostatted quartz cell. The temperature dependence of the observed photoacoustic signal is compared to a theoretical model, and the application of the instrument to the determination of formation constants of metal-ligand complexes at elevated temperatures is discussed. Measurements of the temperature dependence of the formation constant for AmCO3+ are reported