A molecular dynamics study of 1,1-diamino-2,2-dinitroethylene (FOX-7) crystal using a symmetry adapted perturbation theory-based intermolecular force field

Abstract

A dimer potential energy function for 1,1-diamino-2,2-dinitroethylene (FOX-7) has been developed using symmetry adapted perturbation theory based on a Kohn-Sham density functional theory description of the monomers [SAPT(DFT)]. Interaction energies of 1008 dimer configurations were computed in an augmented double zeta basis set and fitted to an atom-atom intermolecular potential energy function of Coulomb plus Buckingham exp-6 form. The potential was used in isothermal-isostress molecular dynamics simulations to study the structure and thermal/pressure response of FOX-7 crystal. The simulated structure is in very good agreement with experiment and the computed thermal/pressure response of the crystal shows significant anisotropy with respect to crystallographic direction, in-line with experimental observations. It is concluded that SAPT(DFT) is an excellent method for development of intermolecular potentials for energetic molecular crystals.

Compatibility Study of 1,1-Diamino-2,2-Dinitroethene (FOX-7) with Some Energetic Materials

“…Since it was reported in 1998 [2], it has quickly been the subject of explosives research in various countries of the world. Many researchers have focused on the theoretical calculation, synthesis, thermal properties, and nanostructure of FOX-7 [3][4][5][6][7][8][9][10]. Previous results on the physical and chemical characterization of FOX-7 have demonstrated that it possesses good thermal and chemical stability.…”

Fabrication of Nanoparticle-Stacked 1,1-Diamino-2,2-Dinitroethylene (FOX-7) Microspheres with Increased Thermal Stability

“…It has aroused the interest of scientific researchers since it was developed in 1998 [2]. A large number of previous studies have shown that FOX-7 has excellent comprehensive performance such as low impact sensitivity and friction sensitivity, high energy density, and detonation velocity and is considered as a substitute for RDX used in the military industry [3][4][5][6][7].…”

Computational studies on two novel energetic nitrogen‐rich compounds based on tetrazolone

“…A new term “Insensitive Munition (IM)” is proposed, and it represents such munitions, which hardly initiate accidentally and are safe to handle, but still possess enough power and reliability to satisfy the requirements needed in the mission . A large number of researches demonstrate that 1,1‐diamino‐2,2‐dinitroethylene (FOX‐7), 5‐nitro‐1,2,4‐triazole‐3‐one (NTO) and 2,4,6‐triamino‐1,3,5‐trinitro‐benzene (TATB) are known as the current promising candidates of insensitive munitions.…”