TATB分子的结构及分子间相互作用

采用Hartree-Fock方法和密度泛函BPW91方法,对TATB双分子系统的几何结构和能量进行了优化和计算,得到双分子共平面的平衡结构.结果表明在TATB分子内部H和O之间存在着明显的氢键.分子之间的相互作用使TATB分子的对称性下降.一般地,没有充分计入分子之间的相互作用的影响时,计算得到的C-N键长比实验测得值大,而计算得到的C-C键长比实验测得值小.计算并讨论了TATB分子之间的相互作用能,表明TATB分子形成晶体结构时,应当以层状晶体结构最为稳定.

Molecular structure and intermolecular reaction of TATB

The geometry and energy of a doubly molecular system are optimized and calculated using Hartree-Fock and density functional(DFT/BPW91) methods. A co-plane structure of the doubly molecular system is obtained. The calculation results show obvious H-bonds between the H and O atoms in TATB. The intermolecular reaction makes the symmetry of TATB reduced. Generally, if the intermolecular reaction is not involved completely, the lengths of C-N bonds obtained theoretically in this paper are longer than those obtained experimentally, and those of C-C bonds obtained theoretically are shorter than those obtained experimentally. The intermolecular reaction energy between two TATB molecules is calculated and discussed. It is shown that a sandwich structure for TATB crystal should be stable.