Complex structure of shock front in single crystal diamond

Diamond's remarkable strength and resistance to extreme pressures make it an ideal material for high-compression applications, particularly as ablative fuel capsules in Inertial Confinement Fusion. Despite extensive experimental work on dynamic compression, a fundamental understanding of the atomic-scale mechanisms of diamond's inelastic deformation and phase transitions, including melting, remains incomplete. To address this critical knowledge gap, we conduct extreme-scale billion-atom molecular dynamics (MD) simulations with quantum accuracy on DOE exascale supercomputers. Our goal is to uncover the complex response of single-crystal diamond to megabar pressures, including orientation-dependent inelastic deformations and melting. These atomic-scale insights into diamond's microstructural evolution will inspire new dynamic compression experiments, complemented by in-situ X-ray diffraction diagnostics at high-energy-density (HED) facilities worldwide.