MD simulations with NequIP were performed using LAMMPS with the pair nequip patch (available at ). By default, a time step of 0.5 fs was used in the MD runs, and was occasionally changed to 0.25 fs to simulate very high temperatures (above 1500 K). The temperature and pressure (when applicable) were controlled using a Nosé-Hoover thermostat and barostat. Temperature and pressure damping parameters were fixed at 100 fs and 1000 fs respectively. Several values around the chosen damping parameters were tested to check their relevance. Simulations were typically performed on a single unit cell for NequIP, and on a 2 × 2 × 2 supercell for Allegro.