An analytical method to quantify the statistics of energy landscapes in random solid solutions
An analytical method to quantify the statistics of energy landscapes in random solid solutions
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DOI：
10.1016/j.commatsci.2022.111763
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发表时间：
2022-02
影响因子：
3.3
通讯作者：
Ritesh Jagatramka;C. Wang;M. Daly
中科院分区：
文献类型：
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作者：
Ritesh Jagatramka;C. Wang;M. Daly
最近对浓缩固溶体的研究强调了不同溶质相互作用在确定各种介观性质中的作用。这些溶质相互作用表现为势能的空间波动，而势能的空间波动是由化学环境的局部变化引起的。尽管对势能波动的观察在文献中有详细记录，但仍然缺乏确定其统计数据的方法。在这里，我们提出了一组解析方程来量化随机排列的固溶体中势能景观的统计数据。我们的方法基于根据溶质配位环境对嵌入原子方法的关系进行重新参数化。最终的方程是通用的，可以应用于不同的晶格和能量景观，只要感兴趣的系统可以通过协调关系组来描述。我们利用这些统计关系来研究几种不同固溶体的内聚能和广义平面断层能量景观。分析预测通过分子静力学模拟进行验证，在大多数情况下都非常一致。该分析的结果为相稳定性和固溶体中“局部”平面断层能量的解释提供了新的见解，这是社区内持续讨论的主题。
Recent studies of concentrated solid solutions have highlighted the role of varied solute interactions in the determination of a wide variety of mesoscale properties. These solute interactions emerge as spatial fluctuations in potential energy, which arise from local variations in the chemical environment. Although observations of potential energy fluctuations are well documented in the literature, there remains a paucity of methods to determine their statistics. Here, we present a set of analytical equations to quantify the statistics of potential energy landscapes in randomly arranged solid solutions. Our approach is based on a reparameterization of the relations of the embedded-atom method in terms of the solute coordination environment. The final equations are general and can be applied to different crystal lattices and energy landscapes, provided the systems of interest can be described by sets of coordination relations. We leverage these statistical relations to study the cohesive energy and generalized planar fault energy landscapes of several different solid solutions. Analytical predictions are validated using molecular statics simulations, which find excellent agreement in most cases. The outcomes of this analysis provide new insights into phase stability and the interpretation of ‘local’ planar fault energies in solid solutions, which are topics of ongoing discussion within the community.