Validating electron pair distribution function analysis: The role of multiple scattering, beam, measurement, and processing parameters

Electron pair distribution function (ePDF), combined with four-dimensional scanning transmission electron
microscopy (4D-STEM), provides a powerful approach for uncovering detailed information about the local
atomic structure and structural variations in disordered materials. However, achieving high accuracy in ePDF
analysis requires careful control of experimental and instrumental parameters. In this study, we systematically
investigate the effect of key electron optical, measurement and processing parameters on ePDF analysis using
simulations as the primary tool, complemented by experimental validation. Specifically, we examine the influ-
ence of diffraction angle range, beam convergence semi-angle, detector pixel resolution, sample thickness
(multiple scattering effect), noise, and electron beam precession on the resulting ePDF. By integrating multi-slice
electron diffraction simulations with experimental diffraction data, we identify optimal conditions for accurate
ePDF extraction and provide practical guidelines to improve analysis precision and reliability. These insights
contribute to refining ePDF techniques, particularly for applications involving amorphous and nanostructured
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materials