Intermolecular interactions, thermodynamic properties, crystal structure, and detonation performance of CL-20/TEX cocrystal explosive

摘要

Density functional theory calculation was performed to investigate the intermolecular interactions, thermodynamic properties, crystal structure, and detonation performance of CL-20 (2,4,6,8,10,12-hexanitrohexaazaisowurtzitane)/TEX (4,10-dinitro-2,6,8,12-tetraoxa-4,10-diaza-tetracyclododecane) cocrystal explosive. The results of natural bond orbital (NBO) and atoms in molecules analysis show that unconventional CH center dot center dot center dot O type hydrogen bonds and dispersion force are the main driving forces for the cocrystal formation. Monte Carlo simulation was employed to predict the crystal structure of the CL-20/TEX cocrystal. The cocrystal is most likely to crystallize in a monoclinic system (space group C2/C), with cell parameters a = 40.62 angstrom, b = 7.35 angstrom, c = 41.36 angstrom, and beta = 157.38 degrees. Based on crystal density, chemical energy, and heat of formations, detonation performance was calculated using Kamlet-Jacobs formulas. Detonation velocity and pressure of the CL-20/TEX cocrystal are higher than those of TEX but a litter lower than those of CL-20. Bond dissociation energy analysis shows that the cocrystal is thermal stable and meets the requirement of high energy density materials.