HMX/FOX-7共晶炸药分子动力学模拟

基于环四甲撑四硝胺(HMX)主要生长面和共晶形成氢键规则，搭建6种HMX/1基于环四甲撑四硝胺(HMX)主要生长面和共晶形成氢键规则，搭建6种HMX/11-二氨基22-二硝基乙烯(FOX-7)共晶模型。采用分子动力学(MD)模拟研究HMX/FOX-7共晶炸药形成的可能性。MD模拟过程中键长、键角、二面角发生严重扭曲。径向分布函数（RDF）考察HMX中氧原子和FOX-7中氢原子或HMX中氢原子和FOX-7中氧原子间的作用力。发现HMX和FOX-7分子间存在较强氢键和范德华力作用。根据最终HMX/FOX-7结构模型，进行结合能和X-射线粉末衍射（XRD）图谱计算。结果表明：6种共晶模型的结合能大小顺序为：E_b(0 2 0)>E_b(1 0 0)>E_b(随机)>E_b(111 )>E_b(102 )>E_b(0 11). 6种共晶模型的XRD衍射峰与纯组分HMX或FOX-7有很大区别。基于晶体生长形貌，结合能和径向分布函数的研究，FOX-7取代HMX（111 ）晶面的共晶模型易于形成。

Molecular Dynamic Simulation of Cyclotetramethylene Tetranitramine/1,1-Diamino-2.2-Dinitroethylene Co-crystal Explosive

Six models of cyclotetramethylene tetranitramine (HMX)/1,1-diamino-2.2-dinitroethylene(FOX-7) co-crystal were constructed based on the main growth faces of HMX crystal and the hydrogen bond rules of co-crystal formation. The probability of HMX/FOX-7 co-crystal formation was investigated using the molecular dynamics (MD) method. The distributions of bond length, angle, and dihedral angle were calculated during MD. As a result, a serious distortion was observed. The radical distribution function (RDF) was used to study the acting force between oxygen atoms in HMX and hydrogen atoms in FOX-7 or hydrogen atoms in HMX and oxygen atoms in FOX-7, which indicates that there are strong hydrogen bonds and Van Der Waals forces between HMX and FOX-7. Binding energies and X-ray powder diffraction (XRD) were calculated on the basis of the final HMX/FOX-7 co-crystal structure. The results show that the orders of binding energies of the six co-crystal models are E_b(020)>E_b(100)>E_b(randomness)>E_b(111 )>E_b (102 )>E_b(011), and the XRD peaks of six co-crystal models are quite different from pure HMX or FOX-7. In view of the research on crystal growth morphology, binding energy and RDF, the model of HMX molecular substituted by FOX-7 on the surface (111 ) of HMX is more liable to form.