Ternary metal hydrides play an essential role in the search for conventional high‐temperature superconductors because they can be synthesized under mild conditions and recovered at ambient pressure. It has been widely accepted that the electronic structure, metallization pressure, and superconducting behavior of binary hydrides can be adjusted effectively by doping, replacing, or introducing a new element. In this work, yttrium hydrides were chosen as parent hydrides, while scandium was considered the doping element to perform systematical crystal structure searches on the Sc‐Y‐H system under pressure. A new ternary hydride ScYH₆ with a Pm‐3 structure (cP8) was found below 150 GPa according to Particle Swarm Optimization calculations, and then, a P4/mmm phase (tP8) becomes favorable from 150 GPa. Importantly, cP8‐ScYH₆ is dynamically stable under pressure as low as 0.01 GPa with a superconducting temperature (T_c) of 32.110 K for Coulomb pseudopotential μ* = 0.13, indicating that ternary hydrides are promising candidates in the search for superconductors that can be synthesized under mild conditions in hydrogen‐rich materials. The analysis using the “triangle straight‐line method”, compared with enthalpy difference calculations, showed that the most reasonable synthesis pathway of ScYH₆ is ScH₃ + YH₃ → ScYH₆ in the whole pressure regime studied in this work. The T_c of ScYH₆ has a linear relationship with pressure up to 52.907 K under 200 GPa. The lattice dynamical calculations demonstrate that the H atoms in both cP8 and tP8 structures make crucial contributions to the superconducting behavior of ScYH₆. These findings can further reveal the influence of doping, replacing, and introducing element on the superconducting behavior of binary hydrides.

中文翻译：

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压力下预测三元氢化物ScYH6的形成和超导性质

三元金属氢化物在寻找常规高温超导体中起着至关重要的作用，因为它们可以在温和条件下合成并在环境压力下回收。人们广泛接受可以通过掺杂，替换或引入新元素来有效地调节二元氢化物的电子结构，金属化压力和超导性能。在这项工作中，钇氢化物被选作母体氢化物，而scan被认为是在压力下对Sc-Y-H系统进行系统晶体结构搜索的掺杂元素。新型三元氢化物ScYH ₆根据粒子群优化计算，发现Pm-3结构（cP8）低于150 GPa，然后从150 GPa变为P4 / mmm相（tP8）。重要的是，对于库仑伪电位μ * = 0.13，cP8-ScYH ₆在低至0.01 GPa的压力下具有32.110 K的超导温度（T _c）动态稳定，这表明三元氢化物是寻找超导体的有希望的候选者。在温和条件下用富氢材料合成。与焓差计算相比，使用“三角形直线法”进行的分析表明，ScYH ₆最合理的合成途径是ScH ₃ + YH ₃  →ScYH ₆在整个压力范围内研究。在200 GPa下，ScYH ₆的T _c与压力高达52.907 K呈线性关系。晶格动力学计算表明，cP8和tP8结构中的H原子均对ScYH ₆的超导行为做出了重要贡献。这些发现可以进一步揭示掺杂，置换和引入元素对二元氢化物超导行为的影响。