Xiao Yiwen, Chen Lang, Geng Deshen, Yang Kun, Lu Jianying, Wu Junying
State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 100081, China.
Phys Chem Chem Phys. 2020 Dec 7;22(46):27002-27012. doi: 10.1039/d0cp04511j.
The contradiction between energy and safety of explosives is better balanced by the host-guest inclusion strategy. Understanding the reaction mechanism of the host-guest explosive is necessary. To deeply analyze the role of the small guest molecules in the host-guest system, a quantum-based molecular dynamics method was used to calculate the initial decomposition reaction of the new host-guest explosive ICM-102/HNO3 against the pure ICM-102 at several high temperatures. The incorporation of HNO3 had no significant influence on the initial decomposition step of ICM-102. Conversely, the earliest intramolecular hydrogen transfer reaction is delayed partly because the H and O atoms of HNO3 connect with the O and H atoms of ICM-102, respectively. As the reaction proceeds, guest molecules get heavily involved in the reaction and increase the reaction rate. The generation rate and quantity of the small oxidizing molecules in the final product were increased significantly in the ICM-102/HNO3 system. These mechanisms revealed that HNO3 molecules inhibit the early stages of the initial decomposition of ICM-102 to some extent, and play an important role in accelerating the decomposition subsequently.
主客体包合策略能更好地平衡炸药的能量与安全性。了解主客体炸药的反应机理很有必要。为深入分析客体小分子在主客体体系中的作用,采用基于量子的分子动力学方法,计算了新型主客体炸药ICM - 102/HNO₃在几个高温下相对于纯ICM - 102的初始分解反应。HNO₃的加入对ICM - 102的初始分解步骤没有显著影响。相反,最早的分子内氢转移反应部分延迟,因为HNO₃的H和O原子分别与ICM - 102的O和H原子相连。随着反应进行,客体分子大量参与反应并提高反应速率。ICM - 102/HNO₃体系中最终产物中小氧化分子的生成速率和数量显著增加。这些机理表明,HNO₃分子在一定程度上抑制了ICM - 102初始分解的早期阶段,并在随后加速分解中起重要作用。