论文标题
基于机器学习的元素替代的晶体结构预测
Crystal structure prediction with machine learning-based element substitution
论文作者
论文摘要
通过给定的化学成分形成的能量稳定晶体结构的预测是固态物理学中的一个核心问题。原则上,可以通过优化能量表面来确定组装原子的结晶状态,而能量表面可以使用第一原理计算来评估。但是,对于复杂系统,例如每个单位细胞原子多原子的系统,使用第一原理计算在势能表面上执行迭代梯度下降非常昂贵。在这里,我们提出了一种晶体结构预测(CSP)的独特方法,该方法依赖于一种称为公制学习的机器学习算法。结果表明,经过大量已鉴定的晶体结构训练的二元分类器可以确定由两个给定的化学成分形成的晶体结构的同构,精度约为96.4 \%。对于具有未知晶体结构的给定查询组成,该模型用于自动从晶体结构数据库中选择一组模板晶体,这些模板晶体具有几乎相同的稳定结构。除了确定模板的局部松弛计算外,该方法不使用从头算计算。对于多种晶体系统,证明了这种基于变电站的CSP的潜力。
The prediction of energetically stable crystal structures formed by a given chemical composition is a central problem in solid-state physics. In principle, the crystalline state of assembled atoms can be determined by optimizing the energy surface, which in turn can be evaluated using first-principles calculations. However, performing the iterative gradient descent on the potential energy surface using first-principles calculations is prohibitively expensive for complex systems, such as those with many atoms per unit cell. Here, we present a unique methodology for crystal structure prediction (CSP) that relies on a machine learning algorithm called metric learning. It is shown that a binary classifier, trained on a large number of already identified crystal structures, can determine the isomorphism of crystal structures formed by two given chemical compositions with an accuracy of approximately 96.4\%. For a given query composition with an unknown crystal structure, the model is used to automatically select from a crystal structure database a set of template crystals with nearly identical stable structures to which element substitution is to be applied. Apart from the local relaxation calculation of the identified templates, the proposed method does not use ab initio calculations. The potential of this substation-based CSP is demonstrated for a wide variety of crystal systems.