MD simulation data: Elastoplastic shock wave in aluminum — defect atom configurations for dislocation-free and pre-deformed cases

This dataset contains molecular dynamics (MD) simulation data supporting the findings reported in: V.S. Krasnikov, P.A. Yakusheva, A.E. Mayer, "Elastoplastic Shock Wave in Aluminum: Role of Initial Dislocation- and Twin-Mediated Plasticity", Computational Materials Science (2026), DOI: [to be added after publication] ── DATASET CONTENTS ── 1. Perfect single-crystal aluminum (initial dislocation density = 0), piston velocity 1000 m/s: Key physics: homogeneous nucleation of Shockley partial dislocations, formation of wide stacking faults and twin layers; no elastic precursor attenuation observed over propagation distances up to 2 μm. 2. Pre-deformed aluminum, initial dislocation density 3×10¹⁶ m⁻², piston velocity 1000 m/s, 500 m/s, 350 m/s Key physics: power-law decay of the elastic precursor amplitude with exponent −0.23 to −0.34, consistent with experimental data. Reduced twin layer formation compared to perfect single-crystal aluminum. At low piston velocity, plasticity governed predominantly by motion of pre-existing dislocations with minimal twin formation. All files contain snapshots of defect atoms. 3. LAMMPS input script: The input script used to run the shock wave simulations is provided for full reproducibility. The script sets up the simulation box, defines the piston and sample groups, applies the EAM interatomic potential for Al, performs initial NPT relaxation at 300 K, and drives the shock wave by moving the piston at a constant velocity along the y-axis (e.g., 10 Å/ps = 1000 m/s). Defect atoms are identified via the centrosymmetry parameter (threshold > 5) and written to dump files every 50 fs (500 steps). The piston velocity parameter should be adjusted to reproduce simulations at 350, 500, and 1000 m/s as described in the paper. ── FILE FORMAT ── Files are stored as compressed archives.Each archive contains LAMMPS dump files with coordinates of defect atoms selected by centrosymmetry parameter > 5, consistent with the criterion used in the paper (see Section 2.1).Files can be visualized using OVITO (https://www.ovito.org). ── SIMULATION PARAMETERS ── - Interatomic potential: EAM, Mishin et al., Phys. Rev. B 59 (1999) 3393- MD code: LAMMPS (Plimpton, J. Comp. Phys. 117, 1995)- Crystallographic orientation: x ∥ [100], y ∥ [010], z ∥ [001]- Initial temperature: 300 K- Ensemble during shock propagation: NVE- Integration timestep: 1 fs ── NOTE ── Full simulation data for all piston velocities and dislocation densities are available from the corresponding author upon reasonable request.