The discovery of high-temperature superconductors remains a central challenge in materials science. Hydrogen-rich compounds are among the most promising candidates, as they can exhibit phonon-mediated superconductivity at elevated critical temperatures, though their stabilization typically requires extreme pressures. % Here, we report the identification of YSbH₆ as a promising superconductor by a multi-stage high-throughput screening on ternary A15-type hydrides, followed by a high-throughput computational search of the Y--Sb--H system, accelerated by ephemeral data derived potentials. % The cubic Pm3 YSbH₆ phase exhibits a predicted critical temperature of 118\, K at 50\, GPa, among the highest T ₂ reported to date for an A15-hydride at this pressure. Thermodynamic analysis shows that YSbH₆ lies 100\, meV/atom above the convex hull at 50\, GPa, but only 26\, meV/atom above the hull at 120\, GPa, suggesting possible metastability and synthesis at similar high pressure conditions. The phase is dynamically stable over a wide pressure range (20--120\, GPa), displays kinetic stability at 50\, GPa and elastic stability at 20 and 50\, GPa, key ingredients for long-lived metastable behaviour at moderate pressures. % These results highlight YSbH₆ as a benchmark case illustrating the balance between high-T ₂ performance and limited thermodynamic stability in ternary hydrides, and underscore the importance of combined dynamic, thermodynamic, kinetic and elastic stability analyses for guiding experimental synthesis of metastable superconductors.
Caussé et al. (Sat,) studied this question.