Decomposition of a 1,3,5-Triamino-2,4,6-trinitrobenzene Crystal at Decomposition Temperature Coupled with Different Pressures: An ab Initio Molecular Dynamics Study

We performed ab initio molecular dynamics simulations to investigate the initiation mechanisms and subsequent decompositions of a 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) crystal at initial decomposition temperature coupled with different pressures. The initial decomposition step of TATB was found to be the unimolecular intramolecular hydrogen transfer; moreover, this initiation mechanism is independent of the variation of the pressure. However, the intramolecular hydrogen transfer becomes easier to occur when the pressure increases from 1 to 3 GPa and from 4 to 5 GPa, while the situation is just the opposite with the increment of pressure from 3 to 4 GPa and from 5 to 20 GPa. The pressure accelerates subsequent decomposition of TATB with the increase of pressure from 1 to 3 GPa and from 4 to 5 GPa, while it would decelerate the decomposition when the pressure increases from 3 to 4 GPa and from 5 to 20 GPa. The deceleration of the pressure on the decomposition of TATB may be caused by inhibiting initia...