Small‐Angle X‐Ray Scattering Simulation Framework for Validating Microstructure Analysis Methods: Application to the Ruland Streak Method

The Ruland streak method is widely used in small‐angle x‐ray scattering (SAXS) to quantify the length and orientation of scatterers, but lacks systematic error quantification under varying microstructural conditions, limiting its quantitative reliability. In this work, we present a benchmarking and computational verification framework for the Ruland streak method, utilizing simulated SAXS patterns of dilute cylindrical scatterers parameterized by distribution full width at half maximum (FWHM), aspect ratio, and size distribution. This framework is applied to assess the accuracy, limitations, and scope of applicability of the Ruland streak method in microstructural characterization. Furthermore, contour maps of relative errors are presented to quantitatively evaluate the fitting errors of the results, allowing the extracted parameters to more closely approximate the true physical values. In addition, preliminary validation is carried out using oriented gold nanorod samples. Although the Ruland streak method demonstrates certain computational deviations, the core principles the Ruland streak method embodies remain fundamentally valid. Additionally, by modifying the scattering intensity function, the proposed framework can be extended and applied to error validation for other SAXS‐based methods.