Wang Buwei, Fan Qian, Yue Yunliang
College of Information Engineering, Yangzhou University, Yangzhou, People's Republic of China.
J Phys Condens Matter. 2022 Mar 9;34(19). doi: 10.1088/1361-648X/ac5705.
The prediction of crystal properties has always been limited by huge computational costs. In recent years, the rise of machine learning methods has gradually made it possible to study crystal properties on a large scale. We propose an attention mechanism-based crystal graph convolutional neural network, which builds a machine learning model by inputting crystallographic information files and target properties. In our research, the attention mechanism is introduced in the crystal graph convolutional neural network (CGCNN) to learn the local chemical environment, and node normalization is added to reduce the risk of overfitting. We collect structural information and calculation data of about 36 000 crystals and examine the prediction performance of the models for the formation energy, total energy, bandgap, and Fermi energy of crystals in our research. Compared with the CGCNN, it is found that the accuracy (ACCU) of the predicted properties can be further improved to varying degrees by the introduction of the attention mechanism. Moreover, the total magnetization and bandgap can be classified under the same neural network framework. The classification ACCU of wide bandgap semiconductor crystals with a bandgap threshold of 2.3 eV reaches 93.2%, and the classification ACCU of crystals with a total magnetization threshold of 0.5 reaches 88.8%. The work is helpful to realize large-scale prediction and classification of crystal properties, accelerating the discovery of new functional crystal materials.
晶体性质的预测一直受到巨大计算成本的限制。近年来,机器学习方法的兴起逐渐使得大规模研究晶体性质成为可能。我们提出了一种基于注意力机制的晶体图卷积神经网络,它通过输入晶体学信息文件和目标性质来构建机器学习模型。在我们的研究中,在晶体图卷积神经网络(CGCNN)中引入注意力机制以学习局部化学环境,并添加节点归一化以降低过拟合风险。我们收集了约36000个晶体的结构信息和计算数据,并检验了我们研究中模型对晶体形成能、总能量、带隙和费米能的预测性能。与CGCNN相比,发现通过引入注意力机制,预测性质的准确率(ACCU)能在不同程度上进一步提高。此外,总磁化强度和带隙可以在同一神经网络框架下进行分类。带隙阈值为2.3 eV的宽带隙半导体晶体的分类ACCU达到93.2%,总磁化强度阈值为0.5的晶体的分类ACCU达到88.8%。这项工作有助于实现晶体性质的大规模预测和分类,加速新型功能晶体材料的发现。