CL-20/TNT/DNB三元共晶的分子动力学模拟

摘要

为了探索研究CL-20(六硝基六氮杂异伍兹烷)/TNT(2,4,6-三硝基甲苯)/DNB(1,3-二硝基苯)三元共晶形成的可能性,分别构建了CL-20/TNT/DNB三元共晶结构和CL-20/TNT、CL-20/DNB组成的二元共混物结构,以及CL-20、TNT、DNB三元混合结构.采用分子动力学方法模拟计算了三元共晶体系、二元共混体系和三元混合体系的结合能、内聚能密度、径向分布函数和力学性能.对计算结果进行比较和分析可以得到:CL-20/TNT/DNB共晶结构的结合能大于CL-20/TNT/DNB共混结构、CL-20/TNT与CL-20/DNB二元共混结构的结合能;CL-20/TNT/DNB共混结构、CL-20/TNT与CL-20/DNB二元共混结构内聚能密度小一些,即共混体系克服分子间作用力相对容易,体系稳定性较差;而CL-20/TNT/DNB共晶结构的内聚能密度大一些,体系中分子间的相互作用力较强,体系结构稳定性较好,共晶体系中存在作用强度大、长度也小的氢键作用,有利于CL-20/TNT/DNB共晶体系的形成,对体系感度的降低也有一定意义.%In order to explore the possibility of CL-20/TNT/DNB ternary cocrystal formation,CL-20/TNT/DNB cocrystal structure,blend structure of CL-20/TNT and CL-20/DNB,CL-20/TNT/DNB blends structure were con-structed respectively.The binding energy, cohesive energy density, radial distribution function and mechanical properties of the three systems were calculated by molecular dynamics simulation.By comparing and analyzing the calculated results, it can be concluded that the binding energy of CL-20/TNT/DNB cocrystal structure is larger than that of CL-20/TNT/DNB blends structure, blend structure of CL-20/TNT and CL-20/DNB.CL-20/TNT/DNB blends structure,blend structure of CL-20/TNT and CL-20/DNB has less cohesive energy density.That is to say,for blends system,it is relatively easy to overcome intermolecular forces.The system stability is poor.Howev-er,the cohesive energy density of CL-20/TNT/DNB cocrystal structure is larger,and the interaction between mole-cules is stronger.The system stability is better.In the cocrystal system,there is a hydrogen bond with high strength and small length,which is beneficial to the formation of CL-20/TNT/DNB cocrystal,and has a certain significance to decrease the sensitivity of cocrystal system.