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Atomically precise nanoclusters play an important role in nanoscale catalysis, photonics, and quantum information science. Their nanochemical properties arise from their unique superatomic electronic structures. As the flagship of atomically precise nanochemistry, the Au 25 (SR) 18 nanocluster exhibits tunable spectroscopic signatures that are sensitive to the oxidation state. This work aims to unravel the physical underpinnings of the spectral progression of Au 25 (SR) 18 nanocluster using variational relativistic time-dependent density functional theory. The investigation will focus on the effects of superatomic spin–orbit coupling, its interplay with Jahn–Teller distortion, and their manifestations in the absorption spectra of Au 25 (SR) 18 nanoclusters of different oxidation states.
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This content will become publicly available on March 17, 2026
Unlocking the Photoluminescence and Photostability of Au 11 Clusters through Pt‐Mediated Band‐Gap Engineering
Abstract Au nanoclusters often demonstrate useful optical properties such as visible/near‐infrared photoluminescence, in addition to remarkable thermodynamic stability owing to their superatomic behavior. The smallest of the 8e−superatomic Au nanoclusters, Au11, has limited applications due to its lack of luminescence and relatively low stability. In this work, we investigate the introduction of a single Pt dopant to the center of a halide‐ and triphenylphosphine‐ligated Au11nanocluster, affording a cluster with a proposed molecular formula PtAu10(PPh3)7Br3. Electrochemical and spectroscopic analysis reveal an expansion of the HOMO–LUMO gap due to the Pt dopant, as well as relatively strong near‐infrared (NIR) photoluminescence which is atypical for an M11cluster (λmax= 700 nm, Φ = 1.88 %). The Pt dopant additionally boosted photostability; more than tenfold. Lastly, we demonstrate the application of the PtAu10cluster's NIR photoluminescence in the detection of the nitroaromatic compound 2,4‐dinitrotoluene, with a limit‐of‐detection of 9.52 μM (1.74 ppm). The notable ability of a single central Pt dopant to unlock photoluminescence in a non‐luminescent nanocluster highlights the advantages of heterometal doping in the tuning of both the optical and thermodynamic properties of Au nanoclusters.
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- Award ID(s):
- 2214606
- PAR ID:
- 10629639
- Publisher / Repository:
- Asian Chemical Editorial Society
- Date Published:
- Journal Name:
- Chemistry – An Asian Journal
- Volume:
- 20
- Issue:
- 6
- ISSN:
- 1861-4728
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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