A NEW METHOD FOR DETERMINING QUANTUM YIELDS OF PHOTOCHEMICAL-REACTIONS IN POWDERED ADSORBENT-ADSORBATES

It has been shown that the rate of a photoinduced reaction and the pro pagation of the irradiation light in a powdered adsorbent-adsorbate ca n be described by a nonlinear system of partial differential equations . Based on a series expansion of the concentration and the light inten sities, then equations are derived relating the quantum yields of the photoreactions considered to the experimental reflectance-time curve. The proposed method, thus, enables the quantum yields to be determined without solving the differential equations numerically, and can be re garded as a generalization of the ''initial-slope-method'' developed p reviously for homogeneous samples to the case of light scattering medi a.