(716f) Monte Carlo Simulations of 1,3,5-Triamino-2,4,6-Trinitrobenzene (TATB): Pvt Data, Phase Equilibria, and Solubility

The transferable force field for phase equilibria (TraPPE) force field is extended to nitro and amino substituents for aromatic rings via parameterization to the vapor-liquid coexistence curves of nitrobenzene and aniline, respectively. These groups were then transferred to model 1,3,5-triamino-2,4,6-trinitrobenzene (TATB). Without any further parameterization to solid state data, the TraPPE force field is able to predict TATB's unit cell lengths and angles at 295 K with mean unsigned percentage error (MUPE) of 0.3 and 1.1% and the specific density within 1%. These predictions are comparable in accuracy to the GRBF model [Gee et al., J. Chem. Phys. 120, 7059 (2004)] that was parameterized directly to TATB's solid state properties. Both force fields are able to reproduce the pressure dependence of TATB's unit cell volume, but they underestimate its thermal expansion. Due to its energetic nature and unusually large cohesive energy, TATB is not chemically stable at temperature in its fluid range and its solubility in common solvents is very low. Gibbs ensemble simulations are used to predict TATB's vapor-liquid coexistence curve at elevated temperatures, melting point, and solubility in common solvents and two ionic liquids.