Crystal structure of the 1:1 cocrystal 5,5′-(triaz-1-ene-1,3-di­yl)bis­(3-nitro-1H-1,2,4-triazole)–tri­ethylammonium nitrate

Abstract

The tri­ethyl­ammonium nitrate cocrystal of 5,5′-(triaz-1-ene-1,3-di­yl)bis­(3-nitro-1H-1,2,4-triazole), obtained unintentionally from 3-amino-5-nitro-1,2,4-triazole (ANTA), exhibits extensive hydrogen bonding and modulation by pseudo-translation with Z* = 4.

The tri­ethyl­ammonium nitrate cocrystal of 5,5′-(triaz-1-ene-1,3-di­yl)bis­(3-nitro-1H-1,2,4-triazole), C₄H₃N₁₁O₄·C₆H₁₆N·NO₃ (3), was obtained unintentionally as the product of an attempted synthesis of a heterocyclic C-bromo­nitrilimine from 3-amino-5-nitro-1,2,4-triazole (ANTA). In the solid state at 150 K, the structure of 3 is modulated by a pseudo-translation along [010] with Z* = 4 (Z = 8 in P1). Exact translational symmetry is broken by a slight modulation of the triazene mol­ecules and nitrate anions, and by disorder of two of the four tri­ethyl­ammonium cations. An extensive hydrogen-bonding network connects the components of the structure and enables a relatively high density of 1.516 g cm⁻³. This feature, as well as its high nitro­gen content, make this rare triazene-bridged 1,2,4-triazole and possible related similar compounds of inter­est as potential energetic materials.