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Polymorphism in magic-sized Au144(SR)60 clusters.

ABSTRACT: Ultra-small, magic-sized metal nanoclusters represent an important new class of materials with properties between molecules and particles. However, their small size challenges the conventional methods for structure characterization. Here we present the structure of ultra-stable Au144(SR)60 magic-sized nanoclusters obtained from atomic pair distribution function analysis of X-ray powder diffraction data. The study reveals structural polymorphism in these archetypal nanoclusters. In addition to confirming the theoretically predicted icosahedral-cored cluster, we also find samples with a truncated decahedral core structure, with some samples exhibiting a coexistence of both cluster structures. Although the clusters are monodisperse in size, structural diversity is apparent. The discovery of polymorphism may open up a new dimension in nanoscale engineering.

SUBMITTER: Jensen KM

PROVIDER: S-EPMC4911633 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature

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Polymorphism in magic-sized Au144(SR)60 clusters.

Jensen Kirsten M Ø KM Juhas Pavol P Tofanelli Marcus A MA Heinecke Christine L CL Vaughan Gavin G Ackerson Christopher J CJ Billinge Simon J L SJ

Nature communications 20160614

Ultra-small, magic-sized metal nanoclusters represent an important new class of materials with properties between molecules and particles. However, their small size challenges the conventional methods for structure characterization. Here we present the structure of ultra-stable Au144(SR)60 magic-sized nanoclusters obtained from atomic pair distribution function analysis of X-ray powder diffraction data. The study reveals structural polymorphism in these archetypal nanoclusters. In addition to co ...[more]

PMID: 27297400

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