Molecular dynamics simulations of diamond shock compression using different interatomic potentials

Shock wave propagation in diamond crystals were simulated by molecular dynamics (MD) using several interactomic potentials: Reactive Empirical Bond Order (REBO) potential; Screened REBO (S-REBO); and, long-range carbon bond-order potential (LCBOP II). Several shock-wave regimes were observed, including single-wave elastic, plastic, and split two-wave elastic-plastic regimes, as well as a novel steady two-zone elastic-plastic regime. The latter regime is characterized by the leading elastic zone of the metastable material uniaxially compressed above the Hugoniot Elastic Limit, which depends on the specific potential used in the simulations. The results obtained using REBO, S-REBO, and LCBOP II are compared with experiment.