Can cage-like cations function as antagonistic ions towards pentazolate anions?

Abstract

Although numerous non-metallic pentazolate (cyclo-N₅⁻) salts have been synthesized and investigated, no cyclo-N₅⁻ salt containing cage-like cations has been reported to date. To identify how cage-like cations impact the structures and properties of cyclo-N₅⁻ salts, we synthesized and examined two cyclo-N₅⁻ salts (C₁₀H₁₈N₆ and C₆H₁₄N₁₂) based on cage-like cations. Furthermore, the structures and performances of these cyclo-N₅⁻ salts were compared. The results suggest that the cyclo-N₅⁻ salts based on cage-like cations possess good insensitivity (IS > 40 N, FS > 360 J), which provides a good idea for developing new energetic salts with low sensitivity. Furthermore, we compared C₆H₁₄N₁₂ with chain-like cationic pentazolate salt based on a similar structure and reported that C₆H₁₄N₁₂ demonstrated improved density and detonation performance. This result indicates that selecting cage-like cations as antagonistic ions to cyclo-N₅⁻ anions may be an improved choice compared to chain-like cations having similar structures.