Chemiluminescence accompanying the co-oxidation of a mixture consisting of cumene and tetraline

The co-oxidation of a mixture of cumene with tetraline shows a minimum rate of oxygen consumption provided a small percentage of tetraline occurs in the cumene. At the same composition of the mixture the maximum chemiluminescence appears. The luminescence intensity of the mixture consisting of the above solvents changes with temperature much more markedly than that of one obtained experimentally with pure solvents. This result excludes the interpretation hitherto accepted, according to which the preferential termination of unequal peroxy radicals plays a decisive part in this process. The influence of the presence of tetraline on the fragmentation reaction of cumyl oxy radicals is discussed as an important cause of the phenomenon observed.