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Superatom Paramagnetism in Au₁₀₂(SR)₄₄^1-/0/1+/2+ Oxidation States.

ABSTRACT: Gold nanoclusters show distinctive magnetic properties and electronic structure. Nanoclusters of sufficiently small size restructure geometrically to stabilize electronically (e.g., a Jahn-Teller effect), whereas geometric distortion may not be possible in larger nanoclusters. In this work, the charge-state-dependent magnetism of the Au₁₀₂(SPh)₄₄^1-/0/1+/2+ nanocluster is investigated through Evans method NMR measurements. The 2+ charge state is shown as paramagnetic. This suggests that the nanocluster does not distort geometrically to pair electrons. Because the nanocluster lies within the transition range of molecule-like to bulk-like properties, this suggests that the geometric stabilization that becomes important in larger "magic number clusters" may be resistant to electronically driven distortions observed in smaller nanoclusters.

SUBMITTER: Window PS

PROVIDER: S-EPMC7482209 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Superatom Paramagnetism in Au102(SR)441-/0/1+/2+ Oxidation States.

Window Phillip S PS Ackerson Christopher J CJ

Inorganic chemistry 20200224 6

Gold nanoclusters show distinctive magnetic properties and electronic structure. Nanoclusters of sufficiently small size restructure geometrically to stabilize electronically (e.g., a Jahn-Teller effect), whereas geometric distortion may not be possible in larger nanoclusters. In this work, the charge-state-dependent magnetism of the Au102(SPh)441-/0/1+/2+ nanocluster is investigated through Evans method NMR measurements. The 2+ charge state is shown as paramagne ...[more]

PMID: 32090558

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