Molecular dynamics simulations of melting of perfect crystalline hexahydro-1,3,5-trinitro-1,3,5-s-triazine

摘要: The melting mechanism of superheated perfect crystalline hexahydro-1,3,5-trinitro-1,3,5-s-triazine (α-RDX) has been investigated using molecular dynamics simulations with the fully flexible force field developed by Smith and Bharadwaj [J. Phys. Chem. B 103, 3570 (1999)]. Sequential 50ps equilibration constant stress–constant temperature ensemble were performed at 10K intervals over range 300–650K, corresponding to a heating rate 2.0×1011K∕s. A solid-solid phase transition is observed between 480 490K, followed melting, which occurs 500 510K. transition, both displacive rotational, characterized an abrupt decrease in lengths unit cell edges b increase length edge c. conformation new AAE, although axial nitro groups have different changes: one shift more other equatorial. Phases than α-RDX experimentally, however...