Computational Insight Into Nitro and Nitro‐NNO‐azoxy‐Based Oxadiazole Compounds

ABSTRACT Density functional theory was employed to design a series of energetic compounds with an oxadiazole backbone, incorporating –NO 2 and –N 3 O 3 (Nitro‐NNO‐azoxy) explosophoric functionalities. In oxadiazole isomers, the influence of the –N 3 O 3 group on molecular stability is less comprehensively understood compared to compounds with the –NO 2 group. To investigate this, we examined the structure‐property relationships of 14 compounds with oxadiazole backbones, analyzing their electronic structures, heats of formation, detonation properties, and stability. Results reveal these compounds have high positive heats of formation, ranging from 119.8 to 754.0 kJ/mol. The –N 3 O 3 group significantly enhances heat of formation, density, and detonation characteristics. An analysis of the energy gap (Δ E ) in frontier molecular orbitals, free volume (Δ V ), heat of detonation ( Q ), and electrostatic potential indicates moderate sensitivity of the compounds. The compounds display better impact insensitivity than RDX and HMX while maintaining thermal stability. With the –N 3 O 3 explosophoric group, oxadiazole compounds have higher densities (above 1.84 g/cm 3 ) and exhibit strong detonation properties ( D > 8.45 km/s, p > 32.4 GPa), making them promising candidates for energetic materials.