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Title: What Protects the Core When the Thiolated Gold Cluster is Extremely Small?

Abstract

The title question is motivated by the fact that extremely small thiolated-gold clusters such as Au{sub 20}(SR){sub 16} have been isolated, but their undetermined structures cannot be fully rationalized by the present knowledge derived from single-crystal structures of larger clusters. One needs to go beyond the linear monomer (RSAuSR) and V-shaped dimer (RSAuSRAuSR) motifs that were found to protect larger clusters. We hypothesize that the U-shaped trimer motif (RSAuSRAuSRAuSR) is required to protect the core of some extremely small thiolated-gold clusters, which have about 20 or fewer Au atoms. We test this hypothesis by proposing structural models for Au{sub 10}(SR){sub 8} based on two trimer motifs protecting a tetrahedral Au{sub 4} core and for Au{sub 20}(SR){sub 16} based on four trimer motifs protecting an Au{sub 8} core.

Authors:
 [1];  [2];  [3];  [4]
  1. ORNL
  2. University of Puerto Rico
  3. Georgia Institute of Technology
  4. University of Georgia, Athens, GA
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
972318
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Physical Chemistry C; Journal Volume: 113; Journal Issue: 39
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ATOMS; DIMERS; GOLD; HYPOTHESIS; MONOMERS; STRUCTURAL MODELS

Citation Formats

Jiang, Deen, Chen, Wei, Whetten, Robert L, and Chen, Zhongfang. What Protects the Core When the Thiolated Gold Cluster is Extremely Small?. United States: N. p., 2009. Web. doi:10.1021/jp906823d.
Jiang, Deen, Chen, Wei, Whetten, Robert L, & Chen, Zhongfang. What Protects the Core When the Thiolated Gold Cluster is Extremely Small?. United States. doi:10.1021/jp906823d.
Jiang, Deen, Chen, Wei, Whetten, Robert L, and Chen, Zhongfang. Thu . "What Protects the Core When the Thiolated Gold Cluster is Extremely Small?". United States. doi:10.1021/jp906823d.
@article{osti_972318,
title = {What Protects the Core When the Thiolated Gold Cluster is Extremely Small?},
author = {Jiang, Deen and Chen, Wei and Whetten, Robert L and Chen, Zhongfang},
abstractNote = {The title question is motivated by the fact that extremely small thiolated-gold clusters such as Au{sub 20}(SR){sub 16} have been isolated, but their undetermined structures cannot be fully rationalized by the present knowledge derived from single-crystal structures of larger clusters. One needs to go beyond the linear monomer (RSAuSR) and V-shaped dimer (RSAuSRAuSR) motifs that were found to protect larger clusters. We hypothesize that the U-shaped trimer motif (RSAuSRAuSRAuSR) is required to protect the core of some extremely small thiolated-gold clusters, which have about 20 or fewer Au atoms. We test this hypothesis by proposing structural models for Au{sub 10}(SR){sub 8} based on two trimer motifs protecting a tetrahedral Au{sub 4} core and for Au{sub 20}(SR){sub 16} based on four trimer motifs protecting an Au{sub 8} core.},
doi = {10.1021/jp906823d},
journal = {Journal of Physical Chemistry C},
number = 39,
volume = 113,
place = {United States},
year = {Thu Jan 01 00:00:00 EST 2009},
month = {Thu Jan 01 00:00:00 EST 2009}
}
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