ABSTRACT

We have performed quantum-based molecular dynamics (MD) simulations to investigate the initial chemical processes of the TATB under different temperatures. A self-consistent charge density-functional tight-binding (SCC-DFTB) method was employed.The results show that a large number of clusters (such as C₁₂H₁₂O₈N₁₀, C₁₂H₁₂O₁₂N₁₂, C₁₂H₁₂O₆N₉, C₁₈H₁₈O₁₆N₁₇) formed in the initial reaction process, which indicates that the initial heating mainly results in the binding of TATB adjacent molecules rather than their decomposition. Moreover, the stability sequence of bonds is C-C > N-H > C-NH₂ > C-NO₂ in our research, C-NO₂ is the main reaction path at 1500 K, and C-NO₂ and C-NH₂ are the main reaction path at 2000 K. When temperature increase to 2500 K and 3000 K, the homolytic cleavage of the N-NO₂ and C-NH₂ bonds is suppressed, and the C-H bond dissociation becomes the primary pathway for TATB decomposition in its early stages.

摘要

我们进行了基于量子的分子动力学 (MD) 模拟，以研究 TATB 在不同温度下的初始化学过程。采用自洽电荷密度泛函紧束缚（SCC-DFTB）方法。结果表明，大量簇（如C ₁₂ H ₁₂ O ₈ N ₁₀、C ₁₂ H ₁₂ O ₁₂ N ₁₂、 C ₁₂ H ₁₂ O ₆ N ₉ , C ₁₈ H ₁₈ O ₁₆ N ₁₇) 在初始反应过程中形成，这表明初始加热主要导致 TATB 相邻分子的结合而不是它们的分解。此外，我们研究中键的稳定性顺序为CC > NH > C-NH ₂  > C-NO ₂，C-NO ₂是1500 K时的主要反应路径，C-NO ₂和C-NH ₂是主要反应路径在2000 K。当温度升高到2500 K和3000 K时，N-NO ₂和C-NH ₂键的均裂被抑制，CH键解离成为TATB早期分解的主要途径阶段。