Title

Metal Core Bonding Motifs of Monodisperse Icosahedral Au13 and Larger Au Monolayer-Protected Clusters As Revealed by X-ray Absorption Spectroscopy and Transmission Electron Microscopy

Authors

Laurent D. Menard
Huiping Xu
Shang-Peng Gao
Ray D. Twesten
Amanda S. Harper-Leatherman, Fairfield UniversityFollow
Yang Song
Gangli Wang
Alicia D. Douglas
Judith C. Yang
Anatoly I. Frenkel
Royce W. Murray
Ralph G. Nuzzo

Document Type

Article

Article Version

Publisher's PDF

Publication Date

2006

Abstract

The atomic metal core structures of the subnanometer clusters Au13[PPh3]4[S(CH2)11CH3]2Cl2 (1) and Au13[PPh3]4[S(CH2)11CH3]4 (2) were characterized using advanced methods of electron microscopy and X-ray absorption spectroscopy. The number of gold atoms in the cores of these two clusters was determined quantitatively using high-angle annular dark field scanning transmission electron microscopy. Multiple-scattering-path analyses of extended X-ray absorption fine structure (EXAFS) spectra suggest that the Au metal cores of each of these complexes adopt an icosahedral structure with a relaxation of the icosahedral strain. Data from microscopy and spectroscopy studies extended to larger thiolate-protected gold clusters showing a broader distribution in nanoparticle core sizes (183 ± 116 Au atoms) reveal a bulklike fcc structure. These results further support a model for the monolayer-protected clusters (MPCs) in which the thiolate ligands bond preferentially at 3-fold atomic sites on the nanoparticle surface, establishing an average composition for the MPC of Au180[S(CH2)11CH3]40. Results from EXAFS measurements of a gold(I) dodecanethiolate polymer are presented that offer an alternative explanation for observations in previous reports that were interpreted as indicating Au MPC structures consisting of a Au core, Au2S shell, and thiolate monolayer.

Comments

Copyright 2006 American Chemical Society.

The published article is also available on the journal site:

http://pubs.acs.org/doi/abs/10.1021/jp060740f

Publication Title

Journal of Physical Chemistry B

Repository Citation

Menard, Laurent D.; Xu, Huiping; Gao, Shang-Peng; Twesten, Ray D.; Harper-Leatherman, Amanda S.; Song, Yang; Wang, Gangli; Douglas, Alicia D.; Yang, Judith C.; Frenkel, Anatoly I.; Murray, Royce W.; and Nuzzo, Ralph G., "Metal Core Bonding Motifs of Monodisperse Icosahedral Au13 and Larger Au Monolayer-Protected Clusters As Revealed by X-ray Absorption Spectroscopy and Transmission Electron Microscopy" (2006). Chemistry & Biochemistry Faculty Publications. 7.
https://digitalcommons.fairfield.edu/chemistry-facultypubs/7

Published Citation

Menard, Laurent D.; Xu, Huiping; Gao, Shang-Peng; Twesten, Ray D.; Harper, Amanda S.; Song, Yang; Wang, Gangli; Douglas, Alicia D.; Yang, Judith C.; Frenkel, Anatoly I.; Murray, Royce W.; Nuzzo, Ralph G. “Metal Core Bonding Motifs of Monodisperse Icosahedral Au13 and Larger Au Monolayer-Protected Clusters As Revealed by X-ray Absorption Spectroscopy and Transmission Electron Microscopy.” Journal of Physical Chemistry B, 2006, 110 (30), 14564-14573.

DOI

10.1021/jp060740f

Peer Reviewed