Higher performing and less sensitive CN₇⁻-based high-energy-density material

The highest nitrogen-containing binary C-N anion, 5-azido-tetrazolate (CN₇⁻), has attracted significant attention owing to its high-energy content. Due to its relative instability and high sensitivity, it is an ongoing challenge to develop more stable and less sensitive novel materials based on CN₇⁻. Towards this goal, we have stabilized the CN₇⁻ anion without compromising its energetic performance by formation of its NH₃OH⁺ salt containing an additional NH₂OH molecule, [NH₃OH][CN₇][NH₂OH] (2). It possesses the best detonation performance and the lowest mechanical sensitivity among all known CN₇⁻-based materials. The structure-property relationship was elucidated through a careful investigation of the noncovalent interactions in the crystal lattice and the important role of the NH₂OH moiety. In addition, the structurally related compound [NH₃OH][CN₇] (1) was also studied.