Study On Electronic Structures And Properties Of Explosive Molecules Of TATB Series

It should be noted that it is an irreversible trend from molecule chemistry to materials chemistry. The interaction among molecules in composite materials has attracted much attention from chemistry and material science researcher. On the base of theoretically calculation, molecule structure and bonding model of TATB and TNA dynamite molecule were investigated in this thesis. Moreover, the inner information of molecule such as covalent bonds, wave function, state density and atomic lever-occupation probability were also obtained by analysis.Electronic structure and bonding model of TATB, (TATB)n, and TNA are studied by density function and discrete variational (DFT-DVM) method. The ions in TATB are with positive and negative charges in turns. The covalent bond order of C-N(in -NO₂) is less than that of C-C or C-N(in -NH₂), and that of O-H is less than that of C-N or C-C by 10 times. The width of forbid bond near Fermi level is about 2.5 eV. The partial DOS of C, N or O with the negative charge is similar each other, which is different from that with the positive charge. The bonding models of large Ï€ bond, hydrogen bond, HOMO and LUMO are discussed. Electronic structures of (TATB)_n (n=1⁴) and the interactions among TATB molecules are studied. The ions in TATB chain are with positive and negative charges in turns. The charges of ions in the middle molecules of the chain are higher than those in the end molecules. As the formation of O-H bond between molecules and separation of bonding electrons, the strengths of covalent bonds of N-O and N-H in the middle molecules of the chain decrease, but those of C-C and C-N increase. The energy states of the electrons reduce because of the interaction among TATB molecules. The energy states of the electrons reduce because of the interaction among TATB molecules. The absolute values of charge of all ions in TNA decreased, which should be attributed to thebreakage of order between positive and negative charge. The ions bonding strength in TNA is weaker than that of TATB due to the small difference among the distance between ions in TNA and TATB.After the analysis the electronic structure and bonding model and other inner information of TATB and TNA we concluded that the higher stability of TATB should be due to intensified and uniformly distributed orbicular structure beside TATB compared with other TATB type molecules.