All simulations were performed using LAMMPS. 19,20 A timestep of 0.25 fs was used in the MD runs and, the temperature (and pressure when applicable) were controlled using a Nosé-Hoover thermostat (and barostat). Unless otherwise specified, temperature and pressure damping parameters are fixed at 100 fs and 1000 fs respectively. At every stage, several values were tested to check the relevance of this range. By default, constant-pressure (N, P, T ) simulations are performed using an isotropic cell, using the LAMMPS keyword iso. To reduce finite size effects, a (2 × 2 × 2) supercell of ZIF-4 with 2176 atoms was simulated, with periodic boundary conditions as in Yang et al. We checked that it does not significantly affect the properties of the generated glasses (see Figure ).