XANES and EXAFS of dilute solutions of transition metals at XFELs
XANES and EXAFS of dilute solutions of transition metals at XFELs
复制标题
DOI：
10.1107/s1600577519007550
复制
发表时间：
2019-09-01
影响因子：
2.5
通讯作者：
Yano, Junko
中科院分区：
文献类型：
--
作者：
Chatterjee, Ruchira;Weninger, Clemens;Yano, Junko
这项工作已经证明，使用来自XFELs的飞秒x射线脉冲，可以对毫摩尔浓度的金属溶液进行Mn XANES和EXAFS的x射线吸收光谱（XAS）。Mn XAS数据的收集使用两种不同的样品递送方法，瑞利喷射和按需滴注设置，不同浓度的Mn。本文描述了一种基于溶剂散射的XAS光谱归一化的新方法，该方法与高可变脉冲源的数据收集兼容。这些稀释溶液样品的XANES和EXAFS光谱测量结果与使用传统扫描协议在同步加速器源收集的数据吻合良好。这里描述的程序将使基于xfl的XAS在稀释的生物样品上，特别是金属蛋白上，具有低样品消耗。详细介绍了XANES和EXAFS研究中使用的实验设置和数据分析方法。这种方法也将有利于在高重复率的XFEL上进行XAS，如欧洲XFEL， LCLS-II和LCLS-II- he。
This work has demonstrated that X-ray absorption spectroscopy (XAS), both Mn XANES and EXAFS, of solutions with millimolar concentrations of metal is possible using the femtosecond X-ray pulses from XFELs. Mn XAS data were collected using two different sample delivery methods, a Rayleigh jet and a drop-on-demand setup, with varying concentrations of Mn. Here, a new method for normalization of XAS spectra based on solvent scattering that is compatible with data collection from a highly variable pulsed source is described. The measured XANES and EXAFS spectra of such dilute solution samples are in good agreement with data collected at synchrotron sources using traditional scanning protocols. The procedures described here will enable XFEL-based XAS on dilute biological samples, especially metalloproteins, with low sample consumption. Details of the experimental setup and data analysis methods used in this XANES and EXAFS study are presented. This method will also benefit XAS performed at high-repetition-rate XFELs such as the European XFEL, LCLS-II and LCLS-II-HE.