Orientation dependence of shock-induced chemistry in diamond

Molecular dynamics simulations employing a reactive empirical bond order potential are used to study the orientational dependence of shock-induced chemistry in diamond. Even for strong shock waves, the mechanism of bond breaking and shock-induced transition to amorphous carbon is found to depend crucially on the direction of shock wave propagation. For [110] oriented shock waves, high rate shear deformation causes the formation of layered carbon structures while [111] shock waves favor the formation of diamond micrograins separated by amorphous carbon inclusions.