Handbook of Materials Modeling
Handbook of Materials Modeling
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DOI：
10.1007/978-3-319-42913-7
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发表时间：
2018-08
期刊：
影响因子：
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通讯作者：
E. Clouet
中科院分区：
文献类型：
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作者：
E. Clouet
本章回顾了位错的从头算模拟的不同方法论方面。这种模拟现在经常被用来研究位错核，也就是在线缺陷附近的区域，在那里晶体严重扭曲，需要原子描述。这个核心区控制着一些位错的基本性质，比如它们在不同的晶面上滑动的能力。基于密度泛函理论的从头计算为模拟这一核心区提供了一种预测方法。由于位错破坏了晶体的周期性并诱导了长程弹性场，因此已经发展了几种依赖于不同边界条件的具体方法，以允许在具有与从头计算兼容的大小的模拟单元中对这些缺陷进行原子模拟。我们描述了这些可以用从头计算研究位错的不同方法，并介绍了目前用来表征核心结构的不同分析，然后讨论了如何从这种模拟中提取有意义的能量属性。
This chapter reviews the different methodological aspects of the ab initio modeling of dislocations. Such simulations are now frequently used to study the dislocation core, i.e., the region in the immediate vicinity of the line defect where the crystal is so strongly distorted that an atomic description is needed. This core region controls some dislocation fundamental properties, like their ability to glide in different crystallographic planes. Ab initio calculations based on the density functional theory offer a predictive way to model this core region. Because dislocations break the periodicity of the crystal and induce long-range elastic fields, several specific approaches relying on different boundary conditions have been developed to allow for the atomistic modeling of these defects in simulation cells having a size compatible with ab initio calculations. We describe these different approaches which can be used to study dislocations with ab initio calculations and introduce the different analyses which are currently performed to characterize the core structure, before discussing how meaningful energy properties can be extracted from such simulations.