The mechanism of unimolecular decomposition of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane. A computational DFT study.

By using the B3LYP level of density functional theory, possible decomposition reaction pathways of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) in the gas phase have been investigated. We have found several types of reactions for this process: homolytic cleavage of an N-N bond to form the NO2* group; HONO elimination; C-C and C-N bonds breaking leading to ring opening; and H-migration. On the basis of the results of computation scanning of the potential energy surface, the most favorite pathway of CL-20 unimolecular decomposition that results in the formation of the stable aromatic compound 1,5-dihydrodiimidazo[4,5-b:4',5'-e]pyrazine has been proposed.