Theoretical predictions of the decomposition mechanism of 1,3,3-trinitroazetidine (TNAZ)

Abstract

A theoretical study of the decomposition pathways of 1,3,3-trinitroazetidine (TNAZ) is described. Possible decomposition transition-states, intermediates, and products are identified and structures, energies, and vibrational frequencies are determined at the B3LYP/6-31G(d,p) level for these species. Four major pathways are apparent. Two pathways are initiated by the fission of the N–NO2 and C–NO2 bonds to yield radical intermediates, while the other two pathways involve the molecular elimination of HONO. Energy profiles for the pathways and possible routes to some of the experimentally observed species of TNAZ decomposition are presented. The energy required to initiate the NO2 bond fission pathways are 4–8 kcal/mol lower than the HONO elimination pathways. In the gas phase, the NO2 elimination pathways will be the dominant routes for TNAZ decomposition. In the condensed phase, however, this trend may be reversed.