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Title: Variations in electronic states of coumarin hexanethiolate-labeled i-Au25 and bi-Au25 clusters
$${\rm Au}_{25}\lpar {{\rm C}_6{\rm H}_{14}{\rm S}} \rpar_{18}{}^-$$ icosahedron and [Au 25 (PPh) 10 (C 6 H 14 S) 5 Cl 2 ] 2+ bi-icosahedron clusters were synthesized. Ligand exchange reactions were carried out with a new coumarin-derived fluorophore (Cou-SH) to label both clusters. Labeled and unlabeled Au 25 were compared and the changes in the electronic structure were determined. The labeled clusters showed marked changes in electronic states, as evidenced by the quenching in the UV region and enhancement in the near infrared. The quantum yield from Cou-SH decreased and the quantum yield from the labeled Au 25 increased. Second, the authors observed changes in the electrochemical band gap.  more » « less
Award ID(s):
1626326
PAR ID:
10111283
Author(s) / Creator(s):
; ; ; ; ; ; ;
Date Published:
Journal Name:
MRS Communications
ISSN:
2159-6859
Page Range / eLocation ID:
1 to 9
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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