Remarkably, only two quaternary entries, Li₆PS₅Cl and Li₅P(S₂Cl)₂, are found in the Materials Project. For binary and ternary systems, the combined phase diagrams with both known and generated structures for ternary systems in Li-P-S-Cl are provided in Figure (b). The 17 stable structures generated by Chemelon are presented in Supplementary Figure . Many of these are molecular crystals, mirroring some of the known phases such as P2S5 and PCl3 (see Supplementary Figure ); however, we note that some contain molecular fragments or voids that appear unlikely to be stable. While Li₃PS₄ can exist in multiple crystalline forms including α, β, and γ polymorphs, an alternative stable triclinic configuration on the DFT energy landscape, has been generated as shown in Figure (c). In addition, Chemeleon successfully generated novel structures such as Li₂PS₃, Li₃PS₆, LiPS₄, and LiPS₆ with the presence of known thiophosphate motifs characteristic of (P2S6) -and (PS4) 3-. Notably, Li₂PS₃ also exhibits dynamically stability without imaginary vibrational frequencies as shown in Supplementary Figure .