Ground-state characterizations of systems predicted to exhibitL11orL13crystal structures

Abstract

Despite their geometric simplicity, the crystal structures $L{1}_{1}$ (CuPt) and $L{1}_{3}$ (CdPt${}_{3}$) do not appear as ground states experimentally, except in Cu-Pt. We investigate the possibility that these phases are ground states in other binary intermetallic systems, but overlooked experimentally. Via the synergy between high-throughput and cluster-expansion computational methods, we conduct a thorough search for systems that may exhibit these phases and calculate order-disorder transition temperatures when they are predicted. High-throughput calculations predict $L{1}_{1}$ ground states in the systems Ag-Pd, Ag-Pt, Cu-Pt, Pd-Pt, Li-Pd, Li-Pt, and $L{1}_{3}$ ground states in the systems Cd-Pt, Cu-Pt, Pd-Pt, Li-Pd, Li-Pt. Cluster expansions confirm the appearance of these ground states in some cases. In the other cases, cluster expansion predicts unsuspected derivative superstructures as ground states. The order-disorder transition temperatures for all $L{1}_{1}$/$L{1}_{3}$ ground states were found to be sufficiently high that their physical manifestation may be possible.