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Combined Fitting of Small- and Wide-Angle X-ray Total Scattering Data from Nanoparticles: Benefits and Issues
Published
Author(s)
Igor Levin, Anton Gagin, Andrew J. Allen
Abstract
Simultaneous fitting of small- and wide-angle total X-ray scattering data for nanoparticles has been explored using both simulated and experimental signals. The nanoparticle types included core/shell metal and quantum-dot CdSe systems. Explicit incorporation of the small-angle scattering (SAS) data in the fit consistently returned more accurate particle-size distribution parameters than those obtained by fitting the wide-angle scattering (WAS) data alone. In particular, a popular method for fitting the Fourier transform of the WAS data (i.e. a pair-distribution function), in which the omitted SAS part is represented using a parametric function, typically yielded significantly incorrect results. The Pareto optimization method combined with a genetic algorithm has been shown effective for combined fitting of the SAS and WAS data. We proposed an approach for identifying the most optimal solution from the Pareto set.
Levin, I.
, Gagin, A.
and Allen, A.
(2014),
Combined Fitting of Small- and Wide-Angle X-ray Total Scattering Data from Nanoparticles: Benefits and Issues, Journal of Applied Crystallography, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=914719
(Accessed October 11, 2025)