An Electronically Integrating Actinometer for Quantum Yield Determinations of Photochemical Reactions

Abstract

An electronically integrating actinometer is described which is designed to provide routinely continuous reading under daylight conditions of the light flux absorbed in the photochemical sample solution and to exclude experimental errors due to manual handling in chemical actinometry. The detector system is based on the measuring of the flux difference in front and behind the sample cell using the absorption-fluorescence capacity of rhodamine B scintillator coupled with silicon semiconductor photoelements. The differential flux measurement is independent of incident wavelength and proportional to the light quanta absorbed, and it can be programmed to proceed until a preset number of light quanta is absorbed.