Touching the density limits of energetic materials by molecular design

Abstract

In this study, we designed a novel class of caged energetic compounds that integrate the high cage strain characteristics of cubane with the high nitrogen content of isowurtzitane, along with modified nitro explosive groups, to achieve high energy density. Among the designed compounds, CEM-3 demonstrates a molecular density of 2.03 g cm⁻³, accompanied by a detonation velocity and a detonation pressure of 9660 m s⁻¹ and 44.4 GPa, respectively, and its detonation properties are comparable to those of HNIW. CEM-4 possesses a molecular density of 2.08 g cm⁻³, with a detonation velocity and a detonation pressure of 9884 m s⁻¹ and 47.1 GPa, respectively. Its detonation performance surpasses that of both HNIW and ONC, while its safety performance (evaluated by h₅₀) also outperforms that of HNIW and ONC. CEM-5 achieves a molecular density of 2.14 g cm⁻³, which approaches the density limits of the energetic compounds within the CHNO class.