Magnetic Field Effects on the Dynamics of Radical Pairs in Micelles: A New Approach to Understanding the “Cage Effect”

Abstract

ABSTRACT The effect of temperature on the photolysis of dibenzyl ketone and 4‐methyldibenzyl ketone in sodium dodecyl sulfate micelles was studied by laser flash photolysis and product distributions derived from steady‐state photolysis. At high temperatures, the product distribution and radical decay kinetics are primarily due to random encounters of radicals, and the “cage effect” cannot be rationalized by geminate recombination reactions that occur before the radicals escape from the micelles. A mechanism is proposed in which the enhancement of the crosstermination product derived from random encounters is due to the different partitioning of each radical species between the micelles and the aqueous phase, thereby leading to different rates for the self‐termination reactions.