CL-20/MAM共晶的分子动力学模拟

Molecular Dynamics Simulation of CL-20/MAM Cocrystal

摘要

共晶技术是实现含能材料高能量与低感度平衡的重要途径。本文采用分子动力学模拟方法系统研究了六硝基六氮杂异伍兹烷/N-甲基- N^'-甲氧基偶氮氧化物（CL-20/MAM）共晶的形成机理与性能：静电势分析与构型优化结果表明，CL-20 五元环上的H原子与MAM分子中-NO 基团的O原子之间存在稳定的氢键作用，相互作用能最低为-21.06kcal/mol ；通过多晶型预测得到共晶密度为1.668 g/cm³，与实验值 1.721 g/cm³ 接近；晶体形貌模拟结果显示，主导生长晶面为（002），其表面积约为晶体总表面积的52.87% ；径向分布函数分析结果显示，在原子间距为2.28、2.46 与3.87Å处可见明显的特征峰，证实共晶分子间主要通过氢键和范德华力实现稳定的非共价结合。CL-20/MAM共晶具有低能量结构特征与稳定晶体形貌，可在保持 CL-20高能量密度的同时显著降低其感度，研究结果可为设计新型高能低感CL-20基共晶材料提供理论依据。

Abstract

Eutectic technology serves as a crucial approach to balance high energy density and low sensitivity of energetic materials.In this study，molecular simulation methods were employed to systematically investigate the formation mechanism and properties of the hexanitrohexaazaisowurtzitane/methoxy (methyl) diazene oxide (CL-20/MAM) cocrystal.Results of electrostatic potential analysis and configuration optimization indicate that stable hydrogen bonding interactions exist between the H atom on the five-membered ring of CL-20 and the O atom of theNO groups in MAM molecule，with a minimum interaction energy of -21.06kcal/mol .The eutectic density predicted via polymorph prediction is 1.668 g/cm³ ，which is close to the experimental value of 1.721 g/cm³ . Crystal morphology simulation reveals that the dominant growth lattice plane is (002) ，accounting for approximately 52.87% of the total surface area of the crystal.Radial distribution function （RDF）analysis shows that distinct characteristic peaks can be observed at atomic distances of 2.28,2.46 ，and 3.87Å ，confirming that the eutectic molecules are stably bound through non-covalent interactions，primarily hydrogen bonding and van der Waals forces.The CL-20/MAM cocrystal exhibits low-energy structural characteristics and a stable crystal morphology，significantly reducing the sensitivity of CL-20 while retaining its high energy density.These findings provide a theoretical basis for the design of novel high-energy and low-sensitivity CL-20-based eutectic materials.

关键词

CL-20/MAM 共晶 / 分子动力学模拟 / 高能低感

Key words

CL-20/MAM cocrystal / molecular dynamics simulation / high energy density and low sensitivity

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基金资助

辽宁省教育厅高等学校基本科研项目(LJ242510144007)