Fuller Chloe A, Rudden Lucas S P
Swiss-Norwegian Beamlines, ESRF, Grenoble, France.
Institute of Bioengineering, EPFL, Lausanne, Switzerland.
IUCrJ. 2024 Jan 1;11(Pt 1):34-44. doi: 10.1107/S2052252523009521.
Many technologically important material properties are underpinned by disorder and short-range structural correlations; therefore, elucidating structure-property relationships in functional materials requires understanding both the average and the local structures. The latter information is contained within diffuse scattering but is challenging to exploit, particularly in single-crystal systems. Separation of the diffuse scattering into its constituent components can greatly simplify analysis and allows for quantitative parameters describing the disorder to be extracted directly. Here, a deep-learning method, DSFU-Net, is presented based on the Pix2Pix generative adversarial network, which takes a plane of diffuse scattering as input and factorizes it into the contributions from the molecular form factor and the chemical short-range order. DSFU-Net was trained on 198 421 samples of simulated diffuse scattering data and performed extremely well on the unseen simulated validation dataset in this work. On a real experimental example, DSFU-Net successfully reproduced the two components with a quality sufficient to distinguish between similar structural models based on the form factor and to refine short-range-order parameters, achieving values comparable to other established methods. This new approach could streamline the analysis of diffuse scattering as it requires minimal prior knowledge of the system, allows access to both components in seconds and is able to compensate for small regions with missing data. DSFU-Net is freely available for use and represents a first step towards an automated workflow for the analysis of single-crystal diffuse scattering.
许多具有重要技术意义的材料特性都由无序和短程结构相关性所支撑;因此,阐明功能材料中的结构-性能关系需要了解平均结构和局部结构。后者的信息包含在漫散射中,但难以利用,尤其是在单晶系统中。将漫散射分离成其组成成分可以极大地简化分析,并能直接提取描述无序的定量参数。在此,基于Pix2Pix生成对抗网络提出了一种深度学习方法DSFU-Net,该方法将漫散射平面作为输入,并将其分解为分子形状因子和化学短程有序的贡献。DSFU-Net在198421个模拟漫散射数据样本上进行了训练,在本文中未见过的模拟验证数据集上表现极佳。在一个实际实验示例中,DSFU-Net成功地再现了两个成分,其质量足以根据形状因子区分相似的结构模型并精修短程有序参数,得到的值与其他既定方法相当。这种新方法可以简化漫散射分析,因为它对系统的先验知识要求极低,能在数秒内获取两个成分,并且能够补偿有缺失数据的小区域。DSFU-Net可免费使用,代表了迈向单晶漫散射分析自动化工作流程的第一步。