Practice of Kinetics (Comprehensive Chemical Kinetics, Volume 1)

4 ANALYSIS 93p4Fig. 65. Eltenton's RV and ion source. From ref. 311.used from a mechanistic point of Gew. Thus, it has been shown that the formationof CHZ3O9 via reaction (61) may be discounted310.One method for the detection of free radicals depends upon the principle that theelectron energy required to ionise the free radical is less than that required to producethe ionised radical from the parent or other compound. Eltenton3" used thismethod to detect free radicals in pyrolytic and combustion reactions up to pressures,in the RV, of 160torr. His RVandion source are shown inFig. 65. The ionisation andion accelerating chambers were evacuated by two, separate, large diffusion pumps(Pz and P3), while the filament and the analysing chambers were separately evacuatedby smaller pumps (P4). The RV consisted of a spirally-wound double quartztube Q down the centre of which the reactant was introduced. The reaction zoneReferences pp. 104-111