Theoretical Studies on Thermolysis Mechanism and Stability of trans‐1,4,5,8‐Tetranitro‐1,4,5,8‐tetraazadecalin Isomers

Abstract

AbstractA systematic study on the thermolysis mechanism and stability of a series of energetic cyclic nitramines, trans‐1,4,5,8‐tetranitro‐1,4,5,8‐tetraazadecalin isomers, was performed by density functional theory (DFT) and semiempirical molecular orbital (MO) calculations. Bond dissociation energies (BDE) and activation energies (Ea) of the thermolysis processes were computed at the B3LYP/6‐31G∗︁∗︁ and PM3 levels, respectively. The effect of nitroamino groups on the thermal stability and pyrolysis mechanism of the title compounds was evaluated by the BDE and Ea. The correlations among BDE, Ea, bond overlap populations, energies of the frontier orbitals, and energy gaps were examined in detail. The results indicate that thermal stabilities and decomposition mechanisms of the title compounds derived from the BDE, Ea and static electronic parameters are basically consistent. Homolysis of the N–NO2 bond is the initial step in the thermolysis of the title compounds, the meta‐isomers are more stable than the para‐isomers, and the ortho‐isomers are the most sensitive.