First-principles studies on the thermal decomposition behavior of FOX-7

Abstract

The thermal decomposition behavior for the molecular crystal of 1,1-diamino-2,2-dinitroethylene (FOX-7) at high temperature has been simulated using constant-temperature molecular dynamics and density functional theory up to 50 ps. We found that most of the energy is released within the first 15 ps of the reaction. The main products are N₂ and H₂O molecules, and their populations generally increase with time. Some charged groups (like NO₂ ⁺ and OH⁻) observed in the initial stage of decomposition may promote further reaction. High-pressure effect on the thermal decomposition behavior has also been examined by simulating FOX-7 crystals of different densities.