Design and properties prediction of modified CL-20 energetic derivatives

We designed a series of energetic compounds based on the CL-20 molecular skeleton, and the properties including molecular geometric structures, electronic structures, density, heat of formation, detonation performances, and impact sensitivity were evaluated using density functional theory (DFT). The results indicate that five molecules have higher density values than that of Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX; 1.91 g/cm³) and A4 has a larger density value (2.07 g/cm³) than that of CL-20 (2.04 g/cm³). In addition, most of the molecules have better detonation performances and stability than those of CL-20, with A4 showing much greater detonation velocity (9.93 km/s) and pressure (47.32 GPa) than those of CL-20 with a h₅₀ value of 14.02 cm. Taking both excellent detonation performance and low sensitivity into consideration, all seven compounds except for A3 and A5 are considered as potential energetic compounds. These theoretically calculated results would be conducive to the design and synthesis of novel nitramine energetic compounds.