First-principles study of crystalline mono-amino-2,4,6-trinitrobenzene, 1,3-diamino-2,4,6-trinitrobenzene, and 1,3,5-triamino-2,4,6-trinitrobenzene

The electronic structure and thermodynamic properties of crystalline mono-amino-2,4,6-trinitrobenzene (MATB), 1,3-diamino-2,4,6-trinitrobenzene (DATB), and 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) have been comparatively studied using density functional theory in the local density approximation. An analysis of electronic structure shows that the CNO2 bonds in the three solids are easier to be broken in the thermal decomposition than the CNH2 bonds. The calculated thermodynamic properties show that the order of their thermodynamic stability is TATB > DATB > MATB and their decomposition reactions are favorable under high temperature. Finally, an attempt is made to correlate the impact sensitivity of the three solids with their band gap. The result shows that there is the relationship between the band gap and impact sensitivity.