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On the angular anisotropy of the randomly averaged magnetic neutron scattering cross section of nanoparticles.

ABSTRACT: The magnetic small-angle neutron scattering (SANS) cross section of dilute ensembles of uniformly magnetized and randomly oriented Stoner-Wohlfarth particles is calculated using the Landau-Lifshitz equation. The focus of this study is on the angular anisotropy of the magnetic SANS signal as it can be seen on a two-dimensional position-sensitive detector. Depending on the symmetry of the magnetic anisotropy of the particles (e.g. uniaxial, cubic), an anisotropic magnetic SANS pattern may result, even in the remanent state or at the coercive field. The case of inhomogeneously magnetized particles and the effects of a particle-size distribution and interparticle correlations are also discussed.

SUBMITTER: Adams MP

PROVIDER: S-EPMC10161771 | biostudies-literature | 2023 May

REPOSITORIES: biostudies-literature

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On the angular anisotropy of the randomly averaged magnetic neutron scattering cross section of nanoparticles.

Adams Michael P MP Pratami Sinaga Evelyn E Michels Andreas A

IUCrJ 20230501 Pt 3

The magnetic small-angle neutron scattering (SANS) cross section of dilute ensembles of uniformly magnetized and randomly oriented Stoner-Wohlfarth particles is calculated using the Landau-Lifshitz equation. The focus of this study is on the angular anisotropy of the magnetic SANS signal as it can be seen on a two-dimensional position-sensitive detector. Depending on the symmetry of the magnetic anisotropy of the particles (e.g. uniaxial, cubic), an anisotropic magnetic SANS pattern may result, ...[more]

PMID: 36913314

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