CPMD investigation of alpha-RDX and epsilon-CL-20: the transition of deflagration to detonation depending on the self-produced radicals
CPMD investigation of alpha-RDX and epsilon-CL-20: the transition of deflagration to detonation depending on the self-produced radicals
复制标题
α-RDX 和 epsilon-CL-20 的 CPMD 研究：爆燃到爆轰的转变取决于自产生的自由基
DOI：
10.1039/d0cp00050g
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发表时间：
2020
影响因子：
3.3
通讯作者：
Wang Kun
中科院分区：
文献类型：
--
作者：
Zhang Tiantian;Chen Longjiu;Zhang Jianguo;Wang Kun
1，3，5-三硝基氢-1，3，5-三嗪（RDX）和2，4，6，8，10，12-六硝基-2，4，6，8，10，12-六氮杂异伍兹烷（CL-20）是典型的高能硝胺化合物。本文采用Car-Parrinello分子动力学（CPMD）方法模拟了凝聚态α-RDX和ε-CL-20的整体分解途径。它们似乎都有相似的不同的初始分解途径，这是N-NO2键的键断裂。有趣的是，我们发现，连续爆炸是非自发的，没有参与的自制的氢自由基的RDX或氧自由基的CL-20。随着温度的升高，逐渐产生更多的自由基，这进一步激活了熵增加的步骤，导致爆燃向爆震的不可控转变，形成NOx、考克斯和HCN。本文详细、系统地描述了单胞α-RDX和ε-CL-20在升温条件下的分解过程，其分解过程可概括为C3 H6 O 6 N6（RDX）→ NO + HNO + H2 + CO2 + HCHO + HNCN + N2 O和C6 H6 O 12 N12（CL-20）→ NO + HONO +5 HCN + CO2 + N2 O +3 NO2。
1,3,5-Trinitroperhydro-1,3,5-triazine (RDX) and 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) are the classic high energy nitramine compounds. Herein, we performed simulations of the overall decomposition pathways of condensed α-RDX and ε-CL-20 by applying the Car–Parrinello molecular dynamics (CPMD) method. Both of them appear to have similar distinct initial decomposition pathways, which are the bond cleavages of N–NO2 bonds. Interestingly, we find that the continuous explosion is nonspontaneous without the participation of self-produced hydrogen radicals of RDX or oxygen radicals of CL-20. Increased radicals are produced gradually with increasing temperature, which activates further entropy-increased steps, resulting in the uncontrollable transition of deflagration to detonation with the formation of NOx, COx and HCN. Herein, we provide a detailed and systematic description of the decomposition for unit-cell α-RDX and ε-CL-20 under increased temperature, which can be summarized as C3H6O6N6 (RDX) → NO + HNO + H2 + CO2 + HCHO + HNCN + N2O and C6H6O12N12 (CL-20) → NO + HONO + 5HCN + CO2 + N2O + 3NO2.