Liu Zhao, Li Da, Zhuang Quan, Tian Fubo, Duan Defang, Li Fangfei, Cui Tian
State Key Laboratory of Superhard Materials, Jilin University, Changchun, 130012, People's Republic of China.
School of Physical Science and Technology, Ningbo University, Ningbo, 315211, People's Republic of China.
Commun Chem. 2020 Apr 2;3(1):42. doi: 10.1038/s42004-020-0286-1.
The lower decomposition barriers of cyclo-N anions hinder their application as high-energy-density materials. Here, first-principles calculations and molecular dynamics simulations reveal that enhancing the covalent component of the interaction between cyclo-N anions and cations can effectively improve the stability of cyclo-N anions. Taking tellurium hexanitride as a representative, the exotic armchair-like N anions of tellurium hexanitride exhibit resistance towards electronic attack and gain extra stability through the formation of covalent bonds with the surrounding elemental tellurium under high pressures. These covalent bonds effectively improve the chemical barrier and insensitivity of tellurium hexanitride during blasting, which prevents the decomposition of solid cyclo-N salts into molecular nitrogen. Furthermore, the high-pressure induced covalent bonds between cyclo-N anions and tellurium enable the high bulk modulus, remarkable detonation performance, and high-temperature thermodynamic stability of tellurium hexanitride.
环氮阴离子较低的分解势垒阻碍了它们作为高能量密度材料的应用。在此，第一性原理计算和分子动力学模拟表明，增强环氮阴离子与阳离子之间相互作用的共价成分可以有效提高环氮阴离子的稳定性。以六氮化碲为例，六氮化碲奇特的扶手椅状氮阴离子表现出对电子攻击的抗性，并在高压下通过与周围的碲元素形成共价键而获得额外的稳定性。这些共价键有效地提高了六氮化碲在爆炸过程中的化学势垒和不敏感性，从而防止固体环氮盐分解为分子氮。此外，高压诱导的环氮阴离子与碲之间的共价键使六氮化碲具有高体积模量、卓越的爆轰性能和高温热力学稳定性。
