Computational study on the crystal structure, thermodynamic properties, detonation performance and pyrolysis mechanism of a novel high density cage compound 10-(5-nitrimino-1,2,3,4-tetrazol-1-yl)methyl-2,4,6,8,12-pentanitrohexaazaisowurtzitane

Abstract

A novel polynitro cage compound 10-(5-nitrimino-1,2,3,4-tetrazol-1-yl)methyl-2,4,6,8,12-pentanitro-hexaazaisowurtzitane, composed of CL-20 and tetrazole framework, has been designed. DFT-B3LYP/6-31G(d) and molecular mechanics methods are employed to calculate its IR spectrum, heat of formation, thermodynamic properties, and crystal structure. Besides, the stability of this compound is evaluated using the bond dissociation energy. The result shows that the initial step of thermal decomposition is the rupture of N–NO2 bond in the side chain. This compound is most likely to crystallize in the P-1 space group, and corresponding cell parameters are Z = 2, a = 7.65 A, b = 14.30 A, c = 10.36 A, α = 91.53°, β = 50.83°, γ = 89.44°, and ρ = 2.025 g cm−3. Detonation velocity and detonation pressure of this compound are estimated to be 9.090 km s−1 and 38.078 GPa using the Kamlet–Jacobs equation, similar to those of CL-20. Considering detonation performance and thermal stability, this compound meets the requirements of exploitable high energy density materials.