发表机构
Laboratory of Materials Design and Simulation (MADES), Institute of Materials, École Polytechnique Fédérale de Lausanne（洛桑联邦理工学院材料研究所材料设计与模拟实验室）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究重新审视多组分原子簇展开中的化学位基，建立线性ACE与平均原子势的解析映射，证明在数据稀缺时占据数基收敛最快且控制性能最佳，为浓缩合金性质建模提供高效路径。
AI 中文摘要
原子间势是材料原子模拟中的核心工具。原子簇展开（ACE）从从头算数据中参数化此类势，通常采用独热表示编码化学自由度，从而产生化学分层的模型。用于晶格构型簇展开的替代化学表示尚未针对原子间势进行评估。在此，我们重新审视任意化学位基下的多组分ACE。随后，我们建立了拟合线性ACE与描述完全随机合金的平均原子势之间的精确解析映射。我们以Mg-Nd中的溶质结合能和空位形成能，以及Mo-Nb和Cr-W固溶体的混合焓为基准，对基于占据数、切比雪夫和常规ACE基构建的势进行了评估。当训练数据稀缺时，占据数基收敛最快，并能最佳地控制目标材料属性，而常规基和切比雪夫基在再现这些属性方面面临挑战。占据数基同样为无序合金热力学提供了最可靠的平均原子描述。在大数据极限下，三种基表现相同。因此，化学基是决定数据效率的设计选择。对其的显式处理为浓缩合金的热力学、力学和动力学性质的平均原子势开辟了道路。
英文摘要
Interatomic potentials are central tools in the atomistic modeling of materials. The atomic cluster expansion (ACE) parameterizes such potentials from ab initio data, conventionally encoding the chemical degrees of freedom with a one-hot representation that yields chemically stratified models. The alternative chemical representations used in on-lattice configurational cluster expansions have not been assessed for interatomic potentials. Here we revisit the multicomponent ACE for an arbitrary chemical site basis. We then establish an exact analytical mapping between a fitted linear ACE and the average-atom potential that describes a perfectly random alloy. We benchmark potentials built on the occupational, Chebyshev, and conventional ACE bases against solute binding and vacancy formation energies in Mg-Nd, and against the mixing enthalpies of the Mo-Nb and Cr-W solid solutions. When training data are scarce, the occupational basis converges fastest and offers the best control over targeted material properties, while the conventional and Chebyshev bases face challenges in reproducing these properties. The occupational basis likewise yields the most reliable average-atom description of disordered alloy thermodynamics. In the large-data limit the three bases perform identically. The chemical basis is therefore a design choice that governs data efficiency. Its explicit treatment opens a route to average-atom potentials for the thermodynamic, mechanical, and kinetic properties of concentrated alloys.
