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DOE OSTI · 2470305

Iterative Bragg peak removal on X-ray absorption spectra with automatic intensity correction

Abstract

This study introduces a novel iterative Bragg peak removal with automatic intensity correction (IBR-AIC) methodology for X-ray absorption spectroscopy (XAS), specifically addressing the challenge of Bragg peak interference in the analysis of crystalline materials. The approach integrates experimental adjustments and sophisticated post-processing, including an iterative algorithm for robust calculation of the scaling factor of the absorption coefficients and efficient elimination of the Bragg peaks, a common obstacle in accurately interpreting XAS data, particularly in crystalline samples. The method was thoroughly evaluated on dilute catalysts and thin films, with fluorescence mode and large-angle rotation. The results underscore the technique's effectiveness, adaptability and substantial potential in improving the precision of XAS data analysis. While demonstrating significant promise, the method does have limitations related to signal-to-noise ratio sensitivity and the necessity for meticulous angle selection during experimentation. Overall, IBR-AIC represents a significant advancement in XAS, offering a pragmatic solution to Bragg peak contamination challenges, thereby expanding the applications of XAS in understanding complex materials under diverse experimental conditions.

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BibTeXRIS

Shimogawa, Ryuichi, Marcella, Nicholas, O'Connor, Christopher R., Kim, Taek-Seung, Reece, Christian, Lubomirsky, Igor, Frenkel, Anatoly I.. 2024-04-09. Iterative Bragg peak removal on X-ray absorption spectra with automatic intensity correction. https://doi.org/10.1107/s1600577524002327

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