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Title: A topological isomer of the Au 25 (SR) 18 nanocluster
Energetically low-lying structural isomers of the much-studied thiolate-protected gold cluster Au 25 (SR) 18 − are discovered from extensive (80 ns) molecular dynamics (MD) simulations using the reactive molecular force field ReaxFF and confirmed by density functional theory (DFT). A particularly interesting isomer is found, which is topologically connected to the known crystal structure by a low-barrier collective rotation of the icosahedral Au 13 core. The isomerization takes place without breaking of any Au–S bonds. The predicted isomer is essentially iso-energetic with the known Au 25 (SR) 18 − structure, but has a distinctly different optical spectrum. It has a significantly larger collision cross-section as compared to that of the known structure, which suggests it could be detectable in gas phase ion-mobility mass spectrometry.
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Award ID(s):
1726332 1213771
Publication Date:
Journal Name:
Chemical Communications
Page Range or eLocation-ID:
8087 to 8090
Sponsoring Org:
National Science Foundation
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