Computational studies on the heats of formation, energetic properties, and thermal stability of energetic nitrogen-rich furazano[3,4-b]pyrazine-based derivatives

The heats of formation (HOF), energetic properties, and thermal stability for a series of furazano[3,4-b]pyrazine derivatives with different substituents or nitrogen-containing heterocycles were studied by using density functional theory. It is found that -N ₃ or nitrogen-containing heterocycle is an effective structural unit for improving the HOF values of the derivatives. The calculated detonation velocities and detonation pressures indicate that the substitution of -NO ₂, -NF ₂, or NO ₂-substituted heterocycle is very useful for enhancing their detonation performance. An analysis of the bond dissociation energies for several relatively weak bonds suggests that most of the derivatives have good thermal stability. By and large, the N-O bond in the furazano[3,4-b]pyrazine ring is the weakest one and the ring cleavage may happen in thermal decomposition. Considered the detonation performance and thermal stability, three compounds may be considered as the potential candidates of high energy density materials.