运用从头算分子动力学模拟高温耦合爆轰压力条件下α-RDX的分解机理(英文)  

Decomposition Mechanisms ofα-RDX Crystal Under High Temperature Coupled with Detonation Pressure by Ab Initio Molecular Dynamics Simulations

作　　者：向东 吴琼[2] 朱卫华[1] XIANG Dong 1 , WU Qiong 2 , ZHU Wei-hua 1(1. School of Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China; 2. School of Materials Science and Engineering, Nanjing Institute of Technology, Nanjing 211167, Chin)

机构地区：[1]南京理工大学化工学院,江苏南京210094 [2]南京工程学院材料科学与工程学院,江苏南京211167

出　　处：《含能材料》2018年第6期477-482,共6页Chinese Journal of Energetic Materials

基　　金：The NSAF Foundation of National Natural Science Foundation of China and China Academy of Engineering Physics(U1530104); the Science Challenging Program

摘　　要：运用从头算分子动力学模拟了α-黑索今(RDX)晶体在高温(3000K)耦合爆轰压力(34.5GPa)下的初始和随后的分解机理。采用两种范德瓦尔斯修的修正方法(PBE-G06和PBE-TS)环境条件下对RDX的晶体结构进行了优化。结果表明,PBE-TS非常合适优化RDX。RDX分解中,C—H键均裂引发α-RDX分解。态密度的结果也证明了C—H键断键的现象。分解过程中发生了HONO的消去反应。产生NO_2、NO、N_2O、N_2、HONO、N_2O_4、H、O—H、H_2O和CO_2为主要反应,发生在早期阶段。同时,RDX引发后的三种不同的分解途径分别为(1)C—N断键引发该环中其它C—N键断裂;(2)N—NO_2断键并且释放NO_2气体;(3)H自由基和氧原子碰撞形成O—H键后释放O—H自由基。The initiation and subsequent decomposition mechanisms ofα-RDX crystal under high temperature（3000 K）coupled with detonation pressure（34.5 GPa）were studied by ab initio molecular dynamics simulations.The crystal structure of RDX was relaxed using two types of van der Waals corrections such as PBE-G06 and PBE-TS functional at ambient conditions.The results indicate that the PBE-G06 functional is much suitable for studyingα-RDX.Results show that the decomposition ofα-RDX is triggered by the homolysis of the C—H bond.The DOS clearly validates that the C—H bond is broken.The elimination reaction of HONO during the decomposition is observed.The primary reactions for producing NO2,NO,N2 O,N2,HONO,N2 O4,H,O—H,H2 O,and CO2 occur at very early stages.After the initiation of RDX,there are three different subsequent decomposition pathways.There are three main interesting subsequent decomposition paths include：（1）the C—N bond hemolysis triggers the other C—N bonds of this ring to break;（2）the dissociation of N—NO2 bond releases NO2 gas;（3）the H radical attacks the O atom to release O—H radical by forming O—H bond.

关 键 词：从头算分子动力学 α-黑索今(RDX) 初始反应 分解 

分 类 号：TJ5[兵器科学与技术—军事化学与烟火技术] O64[理学—物理化学]