Shock-induced phase transition in diamond

Abstract

Abstract. Shock wave propagation in diamond along the [110] crystallographic direction was simulated by molecular dynamics (MD) using the reactive empirical bond order (REBO) potential. A new regime of shock wave propagation was observed involving split elastic − elastic shock waves for the range of piston velocities between 2.0 and 4.1 km/s, and longitudinal stresses 126-278 GPa. The two-wave elastic-elastic splitting is caused by a stress-induced structural phase transition from a standard, low-pressure, to a highpressure phase of REBO diamond, which takes place in the interval of pressures below the Hugoniot elastic limit. The observed phase coexistence in the second elastic shock wave is associated with a non-monotonic longitudinal stress-strain relationship upon uniaxial compression along [110] crystallographic direction.

Molecular dynamics simulation of orientation dependency in the shock-induced phase transition of C60 fullerene single crystals into amorphous diamond

“…[21] Utilizing the REBO potential, they observed a new regime of the shock-wave propagation containing split elastic-elastic shock waves. They concluded a solid-solid PT for the shock compressed diamond.…”