AI 中文总结
本文提出涌现三元稳定化能ΔE3，量化三元化合物超越二元凸包的额外稳定性，揭示其热力学价值与组成复杂性的关联。
AI 中文摘要
稳定的三元化合物位于传统凸包上所有竞争相之下，但这并不能揭示其稳定性是继承自已有有利的二元化合物，还是通过将三种元素结合到同一晶体中而创造的。我们定义了涌现三元稳定化能ΔE3，即稳定三元化合物在相同组成下低于完整一元-二元凸包的能量。应用于GGA框架内计算的19,209个Materials Project化合物，ΔE3的中位数为63.3 meV/原子，范围从几乎与二元简并的相到稳定化达数百meV/原子的化合物。该分布区分了可识别的化学极限：金属间化合物具有最小的中位稳定化，单阴离子化合物占据宽泛的中间区域，而多阴离子化合物获得最大的增益。在单阴离子族内，大的ΔE3与阳离子电负性对比、带隙开启以及相对于实际二元分解产物的配位、键几何和局部邻居化学的重构相关。实验关联的化合物从中获得的中位三元稳定化占其形成能的4.92%，而理论化合物为3.53%，其中在硫化物和硒化物中分离最为明显。因此，ΔE3提供了组成复杂性热力学价值的紧凑度量：低值识别出稳定性主要可由二元化合物复现的相，而高值识别出从三元特有的电子和结构组织中显著获益的化合物。
英文摘要
Stable ternary compounds lie below every competing phase on a conventional convex hull, but this does not reveal whether their stability is inherited from already favorable binaries or created by bringing three elements into one crystal. We define the emergent ternary stabilization energy, delta E3, as the energy by which a stable ternary lies below the complete unary-binary hull at the same composition. Applied to 19,209 Materials Project compounds calculated within the GGA framework, delta E3 has a median of 63.3 meV/atom and spans from nearly binary-degenerate phases to compounds stabilized by several hundred meV/atom. The distribution separates recognizable chemical limits: intermetallics have the smallest median stabilization, single-anion compounds occupy a broad intermediate regime, and polyanion compounds receive the largest gains. Within single anion families, large delta E3 is associated with cation electronegativity contrast, bandgap opening, and reconstruction of coordination, bond geometry, and local neighbour chemistry relative to the actual binary decomposition products. Experimentally linked compounds obtain a median 4.92% of their formation energy from ternary stabilization, compared with 3.53% for theoretical compounds, with the clearest separation in sulphides and selenides. delta E3 therefore provides a compact measure of the thermodynamic value of compositional complexity: low values identify phases whose stability is largely reproducible by binaries, while high values identify compounds that gain substantially from ternary specific electronic and structural organization.
Comments68 pages, 7 figures, 8 supplementary figures, 9 supplementary tables
