FP-DeErr convex-hull and elemental-ordering benchmark subsets: ternary chalcogenide phase-change materials

The convex-hull subset retains only the lowest-energy ordering of each phase and composition, giving 597 unique structures across 22 binary-binary tie-line systems: 561 ternary structures at intermediate compositions and 36 binary endpoint structures taken from Materials Project entries, with an endpoint shared by more than one tie line counted once.

The ordering subset retains groups with at least 20 orderings and keeps the 20 lowest-energy orderings per group, giving 6,100 structures across 305 ordering groups.</p><p dir="ltr"><br></p><p dir="ltr">Ternary hull candidates and ordering entries carry both the initial structure used to start the DFT relaxation and the DFT-relaxed structure, together with the DFT total energy. For the binary endpoints, which come from Materials Project entries, no separate starting geometry was available, so initial_structure is identical to relaxed_structure; endpoint records carry a note recording this.</p><p dir="ltr"><br></p><p dir="ltr">The structures span the composition space of Si, Ge, Sn, Sb, Bi, Ga, In and Ti with Se or Te, generated by interpolating compositions along binary-binary chalcogenide tie lines using isovalent cation or anion substitutions, or aliovalent cation substitutions with charge compensation by cation or anion vacancies.</p><p dir="ltr"><br></p><p dir="ltr">All energies are raw, uncorrected VASP-PBE total energies.