Theoretical study on N‐oxide pentazolate high‐energy‐density materials: Toward excellent energetic performance and good stability

Abstract

The limited energetic performance has been one of major factors restricting the development of pentazolate materials. In this study, the cyclo-N 5 À ring was combined with nitroxide coordinate bonds to form a novel cyclo-N 5 O À anion with higher oxygen contents. From the N-oxide pentazolate anion, nine cyclo-N 5 O À energetic salts (A1-A9) and three covalent compounds (B1-B3) were presented. Density functional theory (DFT) methods were employed to investigate the structures and energetic performance of all compounds. Based on the calculation results, the cyclo-N 5 O À salts A1-A9 exhibit enhanced densities and higher detonation performance than cyclo-N 5 À salts in the previous work. Compounds B1-B3 also feature high densities (1.84-1.94 g cm À3 ) and excellent heats of formation (1011.9-1057.6 kJ mol À1 ). Among all materials, compounds A1, A9, and B1 exhibit remarkable detonation performance (D: 10 138, 9911, 9950 m s À1 ; P: 43.9, 40.9, 41.4 GPa), which are much superior to CL-20. All compounds feature good impact stabilities (h 50 : 11-55 cm). Such excellent energetic performance demonstrates that N-oxide pentazolate derivatives are expected to be promising candidates as high-energy-density materials.