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The most characteristic feature of planar π-aromatics is the ability to sustain a long-range shielding cone under a magnetic field oriented in a specific direction. In this article, we showed that similar magnetic responses can be found in σ-aromatic and spherical aromatic systems. For [Au 13 ] 5+ , long-range characteristics of the induced magnetic field in the bare icosahedral core are revealed, which are also found in the ligand protected [Au 25 (SH) 18 ] − model, proving its spherical aromatic properties, also supported by the AdNDP analysis. Such properties are given by the 8-ve of the structural core satisfying the Hirsch 2( N + 1) 2 rule, which is also found in the isoelectronic [M@Au 12 ] 4+ core, a part of the [MAu 24 (SR) 18 ] 2− (M = Pd, Pt) cluster. This contrasts with the [M@Au 12 ] 6+ core in [MAu 24 (SR) 18 ] 0 (M = Pd, Pt), representing 6-ve superatoms, which exhibit characteristics of planar σ-aromatics. Our results support the spherical aromatic character of stable superatoms, whereas the 6-ve intermediate electron counts satisfy the 4 N + 2 rule (applicable for both π- and σ-aromatics), showing the reversable and controlled interplay between 3D spherical and 2D σ-aromatic clusters.
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This content will become publicly available on January 1, 2026
Surface ligand networking promotes intersystem crossing in the Au 18 (SR) 14 nanocluster
The excited state behavior of Au18(SR)14nanoclusters can be controlled by tailoring the surface ligands; specifically, the aromatic ligands’ networking can promote the intersystem crossing in Au18(SR)14compared to the case of non-aromatic ligands.
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- Award ID(s):
- 2419539
- PAR ID:
- 10629909
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Nanoscale Horizons
- ISSN:
- 2055-6756
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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