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Abstract The crystal structures of 4 ligand‐rotational isomers of Au25(PET)18are presented. Two new ligand‐rotational isomers are revealed, and two higher‐quality structures (allowing complete solution of the ligand shell) of previously solved Au25(PET)18clusters are also presented. One of the structures lacks an inversion center, making it the first chiral Au25(SR)18structure solved. These structures combined with previously published Au25(SR)18structures enable an analysis of the empirical ligand conformation landscape for Au25(SR)18clusters. This analysis shows that the dihedral angles within the PET ligand are restricted to certain observable values, and also that the dihedral angle values are interdependent, in a manner reminiscent of biomolecule dihedral angles such as those in proteins and DNA. The influence of ligand conformational isomerism on optical and electronic properties was calculated, revealing that the ligand conformations affect the nanocluster absorption spectrum, which potentially provides a way to distinguish between isomers at low temperature.
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Facile interconversion of mesitylcopper into a CuMes–Cu 2 bis(amidinate) triangle and a tetracuprous Möbius strip
A rare cuprous triangle featuring a reactive organocopper site is captured by a new flexible bis(amidinate) ligand from the oligomeric mesitylcopper framework and interconverts with another equivalent of ligand into a tetracuprous Möbius strip.
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- PAR ID:
- 10566126
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Chemical Communications
- Volume:
- 60
- Issue:
- 79
- ISSN:
- 1359-7345
- Page Range / eLocation ID:
- 11136 to 11139
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1039/d4cc03935a
