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Nanoparticle imaging. Electron microscopy of gold nanoparticles at atomic resolution.

ABSTRACT: Structure determination of gold nanoparticles (AuNPs) is necessary for understanding their physical and chemical properties, but only one AuNP larger than 1 nanometer in diameter [a 102-gold atom NP (Au102NP)] has been solved to atomic resolution. Whereas the Au102NP structure was determined by x-ray crystallography, other large AuNPs have proved refractory to this approach. Here, we report the structure determination of a Au68NP at atomic resolution by aberration-corrected transmission electron microscopy, performed with the use of a minimal electron dose, an approach that should prove applicable to metal NPs in general. The structure of the Au68NP was supported by small-angle x-ray scattering and by comparison of observed infrared absorption spectra with calculations by density functional theory.

SUBMITTER: Azubel M

PROVIDER: S-EPMC4315941 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

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Nanoparticle imaging. Electron microscopy of gold nanoparticles at atomic resolution.

Azubel Maia M Koivisto Jaakko J Malola Sami S Bushnell David D Hura Greg L GL Koh Ai Leen AL Tsunoyama Hironori H Tsukuda Tatsuya T Pettersson Mika M Häkkinen Hannu H Kornberg Roger D RD

Science (New York, N.Y.) 20140801 6199

Structure determination of gold nanoparticles (AuNPs) is necessary for understanding their physical and chemical properties, but only one AuNP larger than 1 nanometer in diameter [a 102-gold atom NP (Au102NP)] has been solved to atomic resolution. Whereas the Au102NP structure was determined by x-ray crystallography, other large AuNPs have proved refractory to this approach. Here, we report the structure determination of a Au68NP at atomic resolution by aberration-corrected transmission electron ...[more]

PMID: 25146285

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