An empirically optimized classical force-field for molecular simulations of 2,4,6-trinitrotoluene (TNT) and 2,4-dinitrotoluene (DNT).

An empirical classical all-atom specific force-field for use in molecular dynamics simulations (MD) has been developed to reproduce the experimental densities and structures of trinitrotoluene (TNT) in its crystalline and liquid phases at six different temperatures, as well as its enthalpies of sublimation and fusion. The average structural parameters and partial charges were obtained from density functional theory optimizations of single molecules at the B3LYP/6-311+G** level. The other constants for the potential were adjusted in order to obtain a classical force-field, which is able to reproduce the aforementioned properties for TNT with a high degree of accuracy.