Photochemical inhibition in cryogenic reaction systems

Abstract

If diffusion is slow or non-existent in a photochemical system where a large fraction of the incident light is absorbed and reaction is continued to high precentage conversion, account must be taken of both light intensity and consequent concentration gradients when deriving an expression for the rate of photolysis. It is shown how this can be done, in the absence of diffusion, for a parallel-sided film when allowance is made for reactant depletion and competitive light absorption by product species. A digital computer was used to compute product yield-irradiation time curves from the integrated forms of the appropriate rate equations and application of the method to the solid state photolysis of HI is discussed.