Considering the results of our hyperparameter and strategy tests, we performed the active learning with a committee of 6 NNPs, training on ∆E, and adding structures by highest uncertainty. Due to the larger size of the structures (46 atoms/molecule), the uncertainty threshold was set at 2 kJ mol -1 per molecule and batch size set to five structures. Furthermore, to focus the potential towards the lower energy structures we applied a cutoff at 110 kJ mol -1 above the global energy minimum, which gave 2220 candidate structures for training and included all matches to the experimental polymorphs.