论文标题
在$ \ text {ni} _3 \ text {al} $中识别晶核的多维反应坐标
Identification of a Multi-Dimensional Reaction Coordinate for Crystal Nucleation in $\text{Ni}_3\text{Al}$
论文作者
论文摘要
多组分合金中凝固过程中的成核是一个复杂的过程，它包括不同的晶相之间的竞争以及化学组成和有序。在这里，我们将过渡接口采样与广泛的委员会分析相结合，以研究$ \ text {ni} _3 \ text {al} $的成核初始阶段期间的原子机制。来自熔体的结晶簇的形成和生长受三个描述符之间的相互作用的强烈影响：新兴核的大小，结晶度和化学短距离顺序。我们证明，必须在多维反应坐标中包含所有三个特征以正确描述成核机制，尤其是化学短距离顺序在小簇的稳定性中起着至关重要的作用。预期鉴定多维反应坐标的必要性对于复杂的多组分系统中成核过程的原子表征至关重要。
Nucleation during solidification in multi-component alloys is a complex process that comprises the competition between different crystalline phases as well as chemical composition and ordering. Here, we combine transition interface sampling with an extensive committor analysis to investigate the atomistic mechanisms during the initial stages of nucleation in $\text{Ni}_3\text{Al}$. The formation and growth of crystalline clusters from the melt are strongly influenced by the interplay between three descriptors: the size, crystallinity, and chemical short-range order of the emerging nuclei. We demonstrate that it is essential to include all three features in a multi-dimensional reaction coordinate to correctly describe the nucleation mechanism, where in particular the chemical short-range order plays a crucial role in the stability of small clusters. The necessity of identifying multi-dimensional reaction coordinates is expected to be of key importance for the atomistic characterization of nucleation processes in complex, multi-component systems.
