ition reaction of di-tetrazine- tetroxide (DTTO) from quantum molecular dynamics: implications for a promising energetic material†

The initial reaction in compressed DTTO crystal involves an intermolecular oxygen-transfer reaction (barrier 40.1 kcal mol ¬1) that quickly leads to decomposition with the release of one N 2 O molecule. This is quite diff erent from other energetic materials such as RDX, PETN and HMX, for which the initial steps lead to NO 2 dissociation or hydrogen-transfer to eliminate HONO. Di-tetrazine-tetroxide (DTTO) was predicted in 2001 to have a density (up to 2.3 g cm À3) and heat of detonation (up to 421.0 kcal mol À1) better than other explosives, making it the " holy grail " of energetic materials (EMs), but all attempts at synthesis have failed. We report Density Functional Theory (DFT) molecular dynamics simulations (DFT-MD) on DTTO crystal for the two most stable monomers. We predict that the most stable isomer (c1) has a density of r ¼ 1.96 g cm À3 with an estimated detonation velocity (D v) of 9.70 km s À1 and a detonation pressure (D p) of 43.0 GPa, making it comparable to RDX