Addition of Radicals to Molecular Oxygen

The formation of peroxy-radicals and their subsequent reactions play an important role in the oxidation of hydrocarbons at moderate temperatures. The reaction (17) which in the solid phase must strictly involve a third body (the matrix M) has been studied with the rotating cryostat. 

The experimental technique has been described in Section HO. The hydrocarbon radical, R-, is prepared in a suitable matrix and then bombarded by molecular oxygen which is admitted through a third jet. 

spectrum of the peroxy-radical is very different from that of the parent radical, so that the extent of reaction can be determined directly from the composite e.s.r. spectrum of the deposit. For example the spectra of t-butyl and t-butylperoxy radicals and of a deposit containing a mixture of the two radicals are shown in Fig. 14. 

As discussed in an earlier Section (HIE) attempts to form the phenyl-peroxy radical by addition of oxygen to the phenyl radical have been inconclusive. 

speetra of the peroxy-radicals have implications with respect to their reactivity. The two important features of the e.s.r. speetra, which are common to all the radieals, are (i) the absence of any hyperfine interaction with atoms in the substituent group and (ii) the constancy 

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