Detonation properties and sensitivities of a series of -NHNH-/-N = N- bridged tetrazole-based energetic materials

To obtain novel high-energy density compounds with superior detonation properties and sensitivity to those of RDX, a series of furazan/tetrazole/tetrazine-tetrazole-N = N-tetrazole-furazan/tetrazole/tetrazine and furazan/tetrazole/tetrazine-tetrazole-NHNH-tetrazole-furazan/tetrazole/tetrazine-based energetic materials were designed. Their structures were optimised by Gaussian software with density functional theory at B3LYP/6-311G (d,p) level. Based on the optimised structures, their frontier orbital energies, heats of formation and detonation properties were calculated. The results indicate that the compound with tetrazole-tetrazole-N = N-tetrazole-tetrazole parent structure and -N3 energetic group has the highest value of heat of formation while the compound with tetrazine-tetrazole-NHNH-tetrazole-tetrazine parent structure and -C(NO2)3 energetic group possess the highest values of detonation velocity and detonation pressure. Most of the designed compounds have higher values of h50 than those of RDX (28 cm) and HMX (32 cm), and series E had higher average values of impact sensitivity. Finally, taking detonation properties and impact sensitivity into consideration, six compounds (A2, A8, C8, D2, F7 and F8) were selected as potential candidate materials for high-energy density materials, and their electronic and physicochemical properties were investigated.