Merging single-shot XFEL diffraction data from inorganic nanoparticles: a new approach to size and orientation determination.
Merging single-shot XFEL diffraction data from inorganic nanoparticles: a new approach to size and orientation determination.
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合并无机纳米颗粒的单次 XFEL 衍射数据：确定尺寸和方向的新方法
DOI：
10.1107/s2052252517012398
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发表时间：
2017-11-01
期刊：
影响因子：
3.9
通讯作者：
Liu H
中科院分区：
文献类型：
--
作者：
Li X;Spence JCH;Hogue BG;Liu H
提出了一种从X射线自由电子激光(XFEL)散射中恢复尺寸变化的纳米粒子取向的算法。X射线自由电子激光(XFELs)为生物分子、病毒和纳米材料的结构测定提供了新的机会。XFELs具有前所未有的峰值亮度和超短脉冲持续时间，通过利用飞秒级曝光时间可以耐受更高的X射线剂量，因此可以超过传统X射线衍射成像技术所达到的分辨率极限。使用XFELs可以高分辨率地采集单个粒子的散射信息，但粒子的非均质性和未知方向使三维空间中的数据合并变得复杂。利用直线加速器相干光源(LCLS)，采用核壳结构的合成无机纳米晶作为模型系统，进行了原理验证的相干衍射单粒子成像实验。为了处理核壳粒子的非均质性，人们开发了新的计算方法来从散射数据中提取粒子的大小和取向，以辅助数据合并。尺寸分布与电子显微镜的结果一致，合并后的数据支持核壳结构模型。
An algorithm is presented to recover the orientations of nanoparticles with size variations from X-ray free-electron laser (XFEL) scattering. X-ray free-electron lasers (XFELs) provide new opportunities for structure determination of biomolecules, viruses and nanomaterials. With unprecedented peak brilliance and ultra-short pulse duration, XFELs can tolerate higher X-ray doses by exploiting the femtosecond-scale exposure time, and can thus go beyond the resolution limits achieved with conventional X-ray diffraction imaging techniques. Using XFELs, it is possible to collect scattering information from single particles at high resolution, however particle heterogeneity and unknown orientations complicate data merging in three-dimensional space. Using the Linac Coherent Light Source (LCLS), synthetic inorganic nanocrystals with a core–shell architecture were used as a model system for proof-of-principle coherent diffractive single-particle imaging experiments. To deal with the heterogeneity of the core–shell particles, new computational methods have been developed to extract the particle size and orientation from the scattering data to assist data merging. The size distribution agrees with that obtained by electron microscopy and the merged data support a model with a core–shell architecture.