The role of absorption in three-dimensional electron diffraction dynamical structure refinement
arXiv:2602.08935
The paper investigates how absorption influences three‑dimensional electron diffraction data, deriving analytical expressions, performing many‑beam simulations, and showing that accounting for absorption improves dynamical structure refinements, especially for high‑Z crystals at larger thicknesses.
Abstract
The role of absorption in 3D electron diffraction is established through analytical theory, simulation, and dynamical refinement. A two-beam expression for the absorbed integrated intensity in centrosymmetric crystals is derived, showing that for reflections follow a uniform exponential decay set by the mean absorptive potential . Many-beam simulations of both centrosymmetric and non-centrosymmetric crystals reveal additional reflection-specific anomalous absorption beyond the uniform attenuation set by . Neglecting these effects in dynamical refinement of integrated intensities incurs an error that increases approximately linearly with thickness, with this error becoming more severe near zone axes. Dynamical refinements were performed on CsPbBr, quartz, and borane, with the inclusion of absorption yielding an improvement in from to \% for CsPbBr and negligible improvements for quartz and borane. Anomalous absorption may therefore be ignored for routine refinement of integrated intensities except in high- materials at thicknesses approaching .