Electronic structure of solid 1,3,5-triamino-2,4,6-trinitrobenzene under uniaxial compression: Possible role of pressure-induced metallization in energetic materials

The electronic structure of the energetic crystalline solid TATB (1,3,5-triamino-2,4,6-trinitrobenzene) has been studied as a function of uniaxial compression, in order to examine the insulator-to-metal transition. Both ab initio density-functional theory and configuration interaction methods have been used to determine band gaps. Band-gap closure is found to begin near 47% uniaxial strain. A lower bound for the metallization pressure is predicted at 120 GPa, far above the detonation pressure of TATB. Therefore, we conclude that electronic excitation is not involved in the initial stages of detonation for defect-free crystalline TATB.