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DOE OSTI · 2440455

Quantitative x-ray scattering of free molecules

Ma, Lingyu·Goff, Nathan·Carrascosa, Andrés Moreno·Nelson, Silke·Liang, Mengning·Cheng, Xinxin·Yong, Haiwang·Gabalski, Ian·Huang, Lisa·Crane, Stuart W.·Green, Alice E.·Allum, Felix·Lenzen, Philipp·Muvva, Sri Bhavya·Heald, Lauren F.·Liu, Yusong·Bhattacharyya, Surjendu·Larsen, Kirk A.·Graßl, Martin·Forbes, Ruaridh·Centurion, Martin·Wolf, Thomas J. A.·Kirrander, Adam·Minitti, Michael P.·Weber, Peter M.
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Abstract

Advances in x-ray free electron lasers have made ultrafast scattering a powerful method for investigating molecular reaction kinetics and dynamics. Accurate measurement of the ground-state, static scattering signals of the reacting molecules is pivotal for these pump-probe x-ray scattering experiments as they are the cornerstone for interpreting the observed structural dynamics. Here, this article presents a data calibration procedure, designed for gas-phase x-ray scattering experiments conducted at the Linac Coherent Light Source x-ray Free-Electron Laser at SLAC National Accelerator Laboratory, that makes it possible to derive a quantitative dependence of the scattering signal on the scattering vector. A self-calibration algorithm that optimizes the detector position without reference to a computed pattern is introduced. Angle-of-scattering corrections that account for several small experimental non-idealities are reported. Their implementation leads to near quantitative agreement with theoretical scattering patterns calculated with ab-initio methods as illustrated for two x-ray photon energies and several molecular test systems.

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74 ATOMIC AND MOLECULAR PHYSICSgas-phase x-ray scatteringquantitative analysisx-ray free electron lasers

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Ma, Lingyu, Goff, Nathan, Carrascosa, Andrés Moreno, Nelson, Silke, Liang, Mengning, Cheng, Xinxin, Yong, Haiwang, Gabalski, Ian, Huang, Lisa, Crane, Stuart W., Green, Alice E., Allum, Felix, Lenzen, Philipp, Muvva, Sri Bhavya, Heald, Lauren F., Liu, Yusong, Bhattacharyya, Surjendu, Larsen, Kirk A., Graßl, Martin, Forbes, Ruaridh, Centurion, Martin, Wolf, Thomas J. A., Kirrander, Adam, Minitti, Michael P., Weber, Peter M.. 2024-09-20. Quantitative x-ray scattering of free molecules. https://doi.org/10.1088/1361-6455%2Fad78d0

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