GAS-PHASE PHOTOLYSIS AND GAMMA-RADIOLYSIS OF TETRAMETHYLENIMINE

The gas phase photolyses and γ-radiolyses of tetramethylenimine (TMI) have been studied in the pressure range 2-45 torr, at 300°K. The major products observed in the photolyses are ethylene and hydrogen. Methane and propylene which are minor products in the photolyses are significant products in the γ-radiolyses. It is proposed that low-lying excited states of TMI which are not produced in the photolyses (8.4 eV < hv < 11.8 eV) contribute to the formation of propylene in the γ-radiolyses. Photoionization quantum yields of TMI are 0.05, 0.18 and 0.28 at 147, 123.6 and 106.7-104.8 nm respectively. Comparison with the photoionization yield of cyclopentane suggests that the radiationless decay processes of TMI are slightly faster than those occurring in the isoelectronic cyclopentane. Using the γ-radiolyses mechanism derived in this work, the mass spectrum of TMI and other information from the literature, estimates of the ratio of neutral excited states to ions, gex/gion, in the γ-radiolyses is found to be in the range 1.1-1.3. © 1979.