Discovery of energetic-energetic cocrystal polymorphs with high-energy, low-sensitivity

Herein, a first example of energetic-energetic cocrystal polymorphs with a 1:1 molar ratio was discovered by cocrystallizing CL-20 (2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane) with 1,3-DNP (1,3-dinitropyrazole). These two energetic cocrystal polymorphs (cocrystal 1 and cocrystal 2 ) exhibit distinct crystal packing styles, which leads to significant variations in their physicochemical properties. Notably, cocrystal 2 has a high density of 1.963 g∙cm -3 at 170 K, exhibiting high detonation performances (9187 m∙s -1 ; 38.68 GPa) comparable to HMX (1,3,5,7-tetranitro-1,3,5,7-tetrazocane) meanwhile displaying an improved safety (10 J) relative to RDX (1,3,5-trinitro-1,3,5-triazinane), making it a potential high-energy, low-sensitivity energetic material. This work opens up a new strategy to deeply tune properties of energetic materials by constructing energetic-energetic cocrystal polymorphs. These energetic cocrystal polymorphs represent a new field of energetic materials that has not yet been studied. The first example of energetic-energetic cocrystal polymorphs was discovered by cocrystallizing CL-20 (2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane) with 1,3-DNP (1,3-dinitropyrazole). These energetic-energetic cocrystal polymorphs represent a new field of energetic materials that has not yet been studied.