论文标题
通过机器学习的金属纳米颗粒状态模式的电子密度加速映射
Accelerated Mapping of Electronic Density of States Patterns of Metallic Nanoparticles via Machine-Learning
论文作者
论文摘要
在第一原理密度功能理论(DFT)框架中,准确但快速预测了纳米颗粒(NPS)的电子结构仍然具有挑战性。在此,我们提出了一个机器学习结构,以快速但合理地预测金属NP的状态电子密度(DOS),这是通过主成分分析(PCA)和Crystal Graph卷积神经网络(CGCNN)的结合。通过应用PCA,可以将数学上的高维DOS图像转换为低维矢量。 CGCNN在反映局部原子结构对NP的DOS模式的影响方面起着关键作用,这些材料特征(例如,熔化温度,D电子的数量和原子半径)很容易从周期表中获得。 PCA-CGCNN模型适用于所有纯和双金属NP,其中考虑了少数使用典型DFT方法(例如散装,平板和小型NP)轻松获得的DOS训练集。尽管与DFT计算相比,PCA-CGCNN方法的准确性损失很小,但预测速度比DFT方法的速度快得多,并且不受NPS系统尺寸的影响。我们的方法不仅可以立即应用于预测实际纳米缩放NP的电子结构以实验合成,还可以用于探索原子结构与材料的其他光谱图像数据之间的相关性(例如X射线衍射,X射线衍射,X射线光电子光谱光谱谱,和Raman光谱)。
Within first-principles density functional theory (DFT) frameworks, accurate but fast prediction of electronic structures of nanoparticles (NPs) remains challenging. Herein, we propose a machine-learning architecture to rapidly but reasonably predict electronic density of states (DOS) patterns of metallic NPs via a combination of principal component analysis (PCA) and the crystal graph convolutional neural network (CGCNN). By applying PCA, one can convert a mathematically high-dimensional DOS image to a low-dimensional vector. The CGCNN plays a key role in reflecting the effects of local atomic structures on the DOS patterns of NPs with only a few of material features (e.g., melting temperature, the number of d electrons, and atomic radius) that are easily obtained from a periodic table. The PCA-CGCNN model is applicable for all pure and bimetallic NPs, in which a handful DOS training sets that are easily obtained with the typical DFT method, such as bulk, slab, and small-sized NPs, are considered. Although there is a small loss of accuracy with the PCA-CGCNN method compared to DFT calculations, the prediction speed is much faster than that of DFT methods and is not nearly as affected by the system sizes of NPs. Our approach not only can be immediately applied to predict electronic structures of actual nanometer scaled NPs to be experimentally synthesized, but also be used to explore correlations between atomic structures and other spectrum image data of the materials (e.g., X-ray diffraction, X-ray photoelectron spectroscopy, and Raman spectroscopy).