Novel polymorphs and polytypes of lithium chloride from structure predictions based on charge equilibration via neural network technique

By an extensive structural search using the minima hopping method together with the charge equilibration via neural network technique (CENT) artificial neural network potential, we find several novel lithium chloride structures. Besides reproducing the known low energy phases of LiCl, the structural search reveals 86 new phases of which 42 are energetically lower than the rocksalt phase. We classify our structures based on their structural similarities. While many of them can be considered as polytypes of known structures, there are also entirely unexpected low-density polymorphs that contain empty cages and channels.