关键词: 硝基苯 P, 密度泛函理论, 能带结构, 电子结构, 各向异性

The banding and electronic structures of TATB have been investigated at DFT-B3LYP/6-31 * * level. The relationship between structure and property was discussed. The TATB crystalline is between insulator and semiconductor judged from its band gaps of about 4.1 eV. The heat of sublimation is predicted to be 136.25 kj* mol~(-1), which is in good agreement with the experimental result. It is found that the intermolecular and intramolecular H-bonds exist in TATB crystalline according to the distances between atoms and Mtilliken overlap population. The C-NO_2 bonds of TATB are much weaker than those in other molecules and may be the center to cause explosion for this explosive. The oxygen atoms of-NO_2 groups and hydrogen atoms of- NH2 groups have much more negative and positive charges, respectively. This shows that it is difficult for these atoms to be the acceptors or donors of electrons, indicating that TATB is much chemically stable. The point charge electrostatic potential contours are well-distributed on (001) face, but there are obvious interface on (100) and (010) faces. These results indicate that there is a stronger delocation in the same layer and no (or very weak) interaction between layers for TATB bulk and this may explain the fact of the anisotropy of thermal expansion of TATB.

Key words: NITROBENZENE P, DFT, BAND STRUCTURES, ELECTRONIC STRUCTURE, ANISOTROPY