高等学校化学学报 ›› 2003, Vol. 24 ›› Issue (11): 2035.

• 论文 • 上一篇    下一篇

季戊四醇四硝酸酯晶体能带结构和起爆机理的DFT研究

居学海, 肖鹤鸣   

  1. 南京理工大学化学系, 南京 210094
  • 收稿日期:2003-01-17 出版日期:2003-11-24 发布日期:2003-11-24
  • 通讯作者: 肖鹤鸣(1940年出生),男,教授,博士生导师,从事应用量子化学和分子材料学研究.E-mail:xiao@mail.njust.edu.cn E-mail:xiao@mail.njust.edu.cn
  • 基金资助:

    国家自然科学基金(批准号:20173028);国防科工委基础研究资助;教育部博士后专项基金资助

DFT Studies on Energy Band Structure and Detonation Mechanism of Pentaerythritol Tetranitrate Crystal

JU Xue-Hai, XIAO He-Ming   

  1. Department of Chemistry, Nanjing University of Science and Technology Nanjing 210094, China
  • Received:2003-01-17 Online:2003-11-24 Published:2003-11-24

摘要: 对季戊四醇四硝酸酯(PETN)晶体进行DFT-B3LYP计算,求得其晶格能为-1.000eV,与实验值相近.前沿能带平坦,表明分子轨道能态受分子晶体场的影响较小.硝基O原子的较大贡献和酯O原子的较小贡献共同组成价带上沿态密度,而空带下沿则由硝基O和硝基N原子共同组成,说明-NO2基易于接受电子.O-C键的重叠布居数明显比所有其它键的小,加之O-C键鞍点偏离其中点0.022nm,表明该键易于优先异裂起爆.由重叠布居数可知,分子间O…H存在较小的相互作用,[110]方向的撞击将使O…H距离靠近,因而相互作用加强,还使O-C键上的电子向O原子转移,并大大减小该键的重叠布居数,因而促进了该键的异裂.

关键词: 季戊四醇四硝酸酯, DFT, 感度各向异性, 能带结构, 电子结构

Abstract: The electronic structural properties of pentaerythritol tetranitrate crystal lattice have been studied at B3LYPlevel by DFT method.The calculated crystal lattice energy is-1.000eV, which is comparable to experimental value.The frontier energy bands are generally quite flat, indicating that the molecular orbitaLIs hardly perturbed by the crystalline environment.The oxygen atomSIn nitro group make up lower energy bands with a small component from the ester oxygen, whereas both the nitrogen and oxygen atomSIn nitro group make up the higher energy bands.The overlap population of the O-Cbond is smaller or much smaller than those of another bonds.Also, the O-Cbond saddle point is deviated from the midway by 0.022nm, indicating that the O-Cbond is polarized and is prone to heterolysis resulting in detonation.The [110] shocks result in a closer O…Hcontacting, which promotes the interaction between the nitro oxygen of one molecule and the hydrogen atom of another molecule, makes electron transfer to ester oxygen of the O-Cbond, greatly reduces the overlap population on the O-Cbond and thus facilitates the heterolysis rupture of this bond.

Key words: Pentaerythritol tetranitrate, DFT, Anisotropic sensitivity, Energy band structure, Electronic structure

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