Extracting the morphology of gold bipyramids from small‐angle X‐ray scattering experiments via form factor modelling. Issue 1 (24th January 2023)

• Record Type: Journal Article
• Authors: Lyu, Jieli; Goldmann, Claire; Hamon, Cyrille; Constantin, Doru
• Is Part Of: Journal of applied crystallography. Volume 56:Issue 1(2023)
• Page Start: 214
• Page End: 221
• Publication Date: 2023-01-24
• Subjects: small‐angle X‐ray scattering -- SAXS -- colloids -- bipyramids -- form factors -- transmission electron microscopy -- TEM; Crystallography -- Periodicals; 548.05
• DOI: 10.1107/S1600576722011669
• Languages: English
• ISSNs: 0021-8898

Abstract

Abstract : The use of the bicone model is validated for extracting the form factor of gold bipyramids in solution from small‐angle X‐ray scattering data. Abstract : Accurate shape description is a challenge in materials science. Small‐angle X‐ray scattering (SAXS) can provide the shape, size and polydispersity of nanoparticles by form factor modelling. However, simple geometric models such as the ellipsoid may not be enough to describe objects with complex shapes. This work shows that the form factor of gold nanobipyramids is accurately described by a truncated bicone model, which is validated by comparison with transmission electron microscopy (TEM) data for nine different synthesis batches; the average shape parameters (width, height and truncation) and the sample polydispersity are obtained. In contrast, the ellipsoid model yields worse fits of the SAXS data and exhibits systematic discrepancies with the TEM results.