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Extracting the morphology of gold bipyramids from small-angle X-ray scattering experiments via form factor modelling.

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.

SUBMITTER: Lyu J

PROVIDER: S-EPMC9901920 | biostudies-literature | 2023 Feb

REPOSITORIES: biostudies-literature

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Extracting the morphology of gold bipyramids from small-angle X-ray scattering experiments via form factor modelling.

Lyu Jieli J Goldmann Claire C Hamon Cyrille C Constantin Doru D

Journal of applied crystallography 20230201 Pt 1

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 f ...[more]

PMID: 36777141

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