Theoretical investigation of several 1,2,3,4-tetrazine-based high-energy compounds

The enthalpies of formation of six 1,2,3,4-tetrazine-based compounds were calculated according to the Density Functional Theory BOP/TNP method and by using homodesmotic reaction designs. Their detonation performances, including detonation velocity and pressure, were predicted in terms of the Stine equations. The 1,2,3,4-Tetrazine-based compounds labeled A, B, C, D, and F are powerful high-energy compounds. The detonation performances of A and B, including detonation velocity, and detonation pressure, are superior to that of the current high-energy explosive CL-20. The detonation velocity, detonation pressure, and oxygen balance of 1,2,3,4-tetrazine related oxo derivatives can be improved by partial oxidation of the nitrogen atoms in the tetrazine ring, but further oxidation causes reduction of the enthalpies and specific impulses of the oxo derivatives. Calculation of the molecular resonance energies indicated that E [C₆N₁₂] and F have more negative values, i.e, the ring strain energies of their configurations are high, whereas the resonance energies of C and D are low, only compound B has a very positive resonance energy. Considering energy and stability, B is a promising compound for practical use with both high energy and low sensitivity.