The decomposition of solid azides by electron bombardment

The decomposition of barium and sodium azide at room temperature brought about by electron bombardment using accelerating potentials of 100 to 200V and also the effect of short-period pre-bombardment on the rate of the subsequent thermal decomposition of the barium salt has been studied. Although many characteristics of the reaction are similar to those obtained in the previous investigations using ultra-violet light, there are some marked differences. These are attributed to the higher energies used in the primary beam so that ‘free’ electrons and not excitons are produced and to the large excess of electrons always available during bombardment. The theory proposed previously to explain the effects of pre-irradiation and prolonged photolysis, can, however, be extended to take into account these differences, and thereby provide an adequate mechanism of decomposition.