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Multiple origins of extra electron diffractions in fcc metals.

ABSTRACT: Diffuse intensities in the electron diffraction patterns of concentrated face-centered cubic solid solutions have been widely attributed to chemical short-range order, although this connection has been recently questioned. This article explores the many nonordering origins of commonly reported features using a combination of experimental electron microscopy and multislice diffraction simulations, which suggest that diffuse intensities largely represent thermal and static displacement scattering. A number of observations may reflect additional contributions from planar defects, surface terminations incommensurate with bulk periodicity, or weaker dynamical effects.

SUBMITTER: Walsh F

PROVIDER: S-EPMC11296326 | biostudies-literature | 2024 Aug

REPOSITORIES: biostudies-literature

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Multiple origins of extra electron diffractions in fcc metals.

Walsh Flynn F Zhang Mingwei M Ritchie Robert O RO Asta Mark M Minor Andrew M AM

Science advances 20240802 31

Diffuse intensities in the electron diffraction patterns of concentrated face-centered cubic solid solutions have been widely attributed to chemical short-range order, although this connection has been recently questioned. This article explores the many nonordering origins of commonly reported features using a combination of experimental electron microscopy and multislice diffraction simulations, which suggest that diffuse intensities largely represent thermal and static displacement scattering. ...[more]

PMID: 39093961

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