To explore how intermolecular hydrogen bond (H-bond) interactions enhance the density and stability of energetic molecular systems, the intermolecular H-bonding nature of different dimer isomers derived from a new-generation ecofriendly energetic molecule, 3,6-dihydrazino-s-tetrazine is studied. First-principles calculations showed that the critical point of the electron localization function on H-bonds (H…N) lines increased with the enhancement of the H-bond strength, confirming that covalent properties of H-bonds are more important as their strength is stronger. Further energy decomposition analysis indicates that the induced effect accounts for more than 18% of intermolecular interaction attraction terms in planar isomers, reflecting the indispensable covalent-like feature of H-bonds in energetic molecular systems. Moreover, molecular orbitals exhibit clear delocalization characteristics penetrating H-bond regions, which also provide important evidence for covalent-like features of H-bonds. These findings provide new insights to further understand and even regulate the insensitivity of energetic materials.

中文翻译：

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高能分子 3,6-二肼基-s-四嗪 (DHT) 中分子间氢键的类共价特征

为了探索分子间氢键（H-键）相互作用如何增强高能分子系统的密度和稳定性，来自新一代环保高能分子 3,6-dihydrazino-s- 的不同二聚体异构体的分子间 H-键性质研究了四嗪。第一性原理计算表明，氢键 (H…N) 线上电子局域化函数的临界点随着氢键强度的增强而增加，证实了氢键的共价性质更重要，因为它们的强度是更强。进一步的能量分解分析表明，在平面异构体中，诱导效应占分子间相互作用吸引项的18%以上，反映了高能分子系统中氢键不可或缺的类共价特征。而且，分子轨道表现出清晰的离域特征，穿透氢键区域，这也为氢键的类共价特征提供了重要证据。这些发现为进一步理解甚至调节含能材料的不敏感性提供了新的见解。