Cover Picture: ZAAC ‐ Journal of Inorganic and General Chemistry 3‐4/2010

The cover picture shows the molecular structure of the highly explosive compound 1,7‐diamino‐1,7‐dinitrimino‐2,4,6‐trinitro‐2,4,6‐triazaheptane ( APX ). In the background the detonation of APX is shown. The compound was synthesized in high yield and purity and was characterized by multinuclear NMR ( 1 H, 13 C, 14 N) and vibrational spectroscopy. APX crystallizes in the orthorhombic space group P b nc with a crystal density of ρ = 1.911 g·cm −3 . It decomposes at 174°C. Impact (IS), friction (FS) and electrostatic discharge (ESD) sensitivities were determined experimentally (IS ≥ 3 J,FS ≥ 80 N and ESD ≥ 0.1 J). Polymer bonded mixtures of APX with 5% PVAA resin proved to be less sensitive towards mechanical stimuli (IS ≥ 5J, FS ≥ 160 N). The detonation parameters (EXPLO5 code) were calculated using combined quantum chemical (CBS‐4M) methods and a chemical equilibrium calculation based on the steady‐state model of detonation ( V det = 9540 m·s −1 , p C−J = 395 kbar, Q v = −5935 kJ·kg −1 ). The experimentally determined detonation velocity (fiber optic technique) agrees well with the theoretical values, which indicate that APX shows better detonation performance than HMX (1,3,5,7‐Tetranitro‐1,3,5,7‐tetraazoctane). More details are discussed in the article by T. M. Klapütke et al. on p. 463ff.