Anisotropic Shock Response of Oriented Nitromethane Single Crystals

Detailed anisotropic structural and mechanical responses of crystalline nitromethane subjected to shock loading along different crystallographic orientations have been studied using molecular dynamics (MD) simulations with a nonreactive force field. Single- and multi-particle properties prior to and following shock passage have been evaluated using a geometric binning approach that spatially and temporally resolves the shock-induced thermo-physical and geometric changes in the material. Initial partitioning and redistribution pathways of the energy imparted by the shock wave result in orientation-dependent structural relaxation processes among which are elastic deformation; crystal structure reordering; and plane-specific disordering phenomena, in which certain structural properties undergo changes from ordered to disordered states in some crystallographic planes but not others.