Computer-aided design and property prediction of novel insensitive high-energy heterocycle-substituted derivatives of cage NNNAHP.

A series of new derivatives of cage 2,4,6,8,10,12,13,14,15-nanonitro-2,4,6,8,10,12,13,14, 15-nanoazaheptacyclo[5.5.1.13,11,15,9] pentadecane (NNNAHP) were designed by incorporating combination of heterocyclic and non-heterocyclic substituents and studied by using density functional theory. The results indicate that the -tetrazine and -N(NO2)2 are very beneficial structural fragments to increase their heat of formation. The introduction of different heterocyclic and non-heterocyclic groups can produce different effects on different properties: large densities (1.88-2.06 g cm-3), high detonation velocities (8.17-9.83 km s-1), excellent detonation pressures (30.55-46.02GPa), and outstanding heat of detonations (1169.80-1637.19 cal g-1). The analysis of bond dissociation energy values show that the N(cage)-NO2 is the weakest bond, and it may turn into a trigger bond during detonation. Almost all the derivatives are thermally more stable than the parent compound. All the substituted derivatives are insensitive as compared with the parent compound. According to excellent detonation properties, high thermal stability, and good insensitivity, 10 compounds may be chosen as potential high-energy density compounds.