INFRARED MULTIPHOTON DECOMPOSITION OF DIMETHYLNITRAMINE

The infrared multiphoton dissociation of dimethylnitramine in the gas phase by a pulsed CO2 laser has been studied in order to elucidate its photochemical decomposition mechanism under collisionless conditions and provide a qualitative understanding of the consequent chemical mechanism that leads to the final products. The experimentally determined steady-state rate coefficient for the unimolecular decomposition of dimethylnitramine was found to be k(st) = 105.5±0.1(I/MW cm-2) s-1 for laser intensities 2-10 MW cm-2. Scavenging experiments with Cl2, NOCl, NO, NO2, and (CD3)2NNO2 molecules have shown that the decomposition dynamics proceeds through scission of the N-NO2 bond, with no evidence of the HONO elimination or the isomerization to nitro-nitrite channel. Dimethylnitrosamine was the major final product which was mainly produced through oxidation of dimethylamino radical by dimethylnitramine. © 1990 American Chemical Society.