Computational investigation on 2,6-diamino-3,5-dinitropyridine-1-oxide crystal

Abstract

Density functional theory calculations were performed on crystalline 2,6-diamino-3,5-dinitropyridine-1-oxide (ANPyO). The conduct bands are generally quite flat, while the valence bands are uneven. The carbon, oxygen and amino nitrogen atoms make up the narrow lower energy levels. While the carbon, amino nitrogen and atoms in nitro group make up the higher energy levels. Change of electronic charges for the decrease of the cell edge a and c are almost the same, but different from the decrease of the cell edge b, indicating an anisotropic effect related to compressions. The C-Nitro and the N-O (N-oxide) bonds are the weakest, and tend to rupture upon external stimulation. The Mulliken population for the N-O (N-oxide) bond in crystal is much smaller than that in molecule, indicating that the molecular packing weakens this bond. Judged by the fact of N-O (N-oxide) bond being weaker than C-Nitro bond, ANPyO is sensitive to mechanic impact than 1,3,5-triamino-2,4,6-trinitrobenzene, which is in good agreement with experiment. The crystal lattice energy is predicted to be -166.03 kJ/mol, after being corrected for basis set superposition error.

Interplay of thermochemistry and Structural Chemistry, the journal (volume 21, 2010) and the discipline

“…In the theoretical study by He et al [173], periodic DFT calculation was used to investigate crystalline 2,6-diamino-3,5-dinitropyridine-1-oxide, an important explosive and raw materials for preparing high energetic explosive. The insight into chemical molecular properties was obtained by analyzing band structures, densities of states and charge distributions.…”

Charged Forms of 2,6-Dinitro-1-oxidopyridin-1-ium-3,5-diamine - A DFT Treatment

“…Note that in reference [1], 3,5-diamino-2,6-dinitropyridine-N-oxide also was named as DADNPO. The constitutional isomer of it, namely 2,6-diamino-3,5-dinitropyridine-N-oxide (DADNPO) (II) has ample number of references in the literature [2][3][4][5][6][7], contrary to the presently considered 3,5-diamino isomer (I). Chavez mentioned 3,5-diamino-2,6-dinitropyridine-N-oxide in his book chapter that he and his coworkers attempted to prepare the 2,6dinitro-3,5-diaminopyridine 1-oxide but they were unsuccessful [8].…”