Header

UZH-Logo

Maintenance Infos

Structural information on the Au-S Interface of thiolate-protected gold clusters: A raman spectroscopy study


Varnholt, Birte; Oulevey, Patric; Luber, Sandra; Kumara, Chanaka; Dass, Amala; Buergi, Thomas (2014). Structural information on the Au-S Interface of thiolate-protected gold clusters: A raman spectroscopy study. Journal of Physical Chemistry C, 118(18):9604-9611.

Abstract

The Raman spectra of a series of monolayer-protected gold clusters were investigated with special emphasis on the Au-S modes below 400 cm(-1). These clusters contain monomeric (SR-Au-SR) and dimeric (SR-Au-SR-Au-SR) gold-thiolate staples in their surface. In particular, the Raman spectra of Au-25(2-PET)(18)](0/-), Au-38(2-PET)(24), Au-40(2-PET)(24), and Au-144(2-PET)(60) (2-PET = 2-phenylethylthiol) were measured in order to study the influence of the cluster size and therefore the composition with respect to the monomeric and dimeric staples. Additionally, spectra of Au-25(2-PET)(18-2x) (S-/rac-BINAS)(x) (BINAS = 1,1'-binaphthy1-2,2'-dithiol), Au-25(CamS)(18) (CamS = 1R,4S-camphorthiol), and Au(n)BINAS(m) were measured to identify the influence of the thiolate ligand on the Au-S vibrations. The vibrational spectrum of Au-38(SCH3)(24) was calculated which allows the assignment of bands to vibrational modes of the different staple motifs. The spectra are sensitive to the size of the cluster and the nature of the ligand. Au-S-C bending around 200 cm(-1) shifts to slightly higher wavenumbers for the dimeric as compared to the monomeric staples. Radial Au-S modes (250-325 cm(-1)) seem to be sensitive toward the staple composition and the bulkiness of the ligand, having higher intensities for long staples and shifting to higher wavenumbers for sterically more demanding ligands. The introduction of only one BINAS dithiol has a dramatic influence on the Au-S vibrations because the molecule bridges two staples which changes their vibrational properties completely.

Abstract

The Raman spectra of a series of monolayer-protected gold clusters were investigated with special emphasis on the Au-S modes below 400 cm(-1). These clusters contain monomeric (SR-Au-SR) and dimeric (SR-Au-SR-Au-SR) gold-thiolate staples in their surface. In particular, the Raman spectra of Au-25(2-PET)(18)](0/-), Au-38(2-PET)(24), Au-40(2-PET)(24), and Au-144(2-PET)(60) (2-PET = 2-phenylethylthiol) were measured in order to study the influence of the cluster size and therefore the composition with respect to the monomeric and dimeric staples. Additionally, spectra of Au-25(2-PET)(18-2x) (S-/rac-BINAS)(x) (BINAS = 1,1'-binaphthy1-2,2'-dithiol), Au-25(CamS)(18) (CamS = 1R,4S-camphorthiol), and Au(n)BINAS(m) were measured to identify the influence of the thiolate ligand on the Au-S vibrations. The vibrational spectrum of Au-38(SCH3)(24) was calculated which allows the assignment of bands to vibrational modes of the different staple motifs. The spectra are sensitive to the size of the cluster and the nature of the ligand. Au-S-C bending around 200 cm(-1) shifts to slightly higher wavenumbers for the dimeric as compared to the monomeric staples. Radial Au-S modes (250-325 cm(-1)) seem to be sensitive toward the staple composition and the bulkiness of the ligand, having higher intensities for long staples and shifting to higher wavenumbers for sterically more demanding ligands. The introduction of only one BINAS dithiol has a dramatic influence on the Au-S vibrations because the molecule bridges two staples which changes their vibrational properties completely.

Statistics

Citations

22 citations in Web of Science®
23 citations in Scopus®
Google Scholar™

Altmetrics

Downloads

50 downloads since deposited on 21 Oct 2014
31 downloads since 12 months
Detailed statistics

Additional indexing

Item Type:Journal Article, refereed, original work
Communities & Collections:07 Faculty of Science > Department of Chemistry
Dewey Decimal Classification:540 Chemistry
Language:English
Date:2014
Deposited On:21 Oct 2014 12:26
Last Modified:05 Apr 2016 18:23
Publisher:American Chemical Society
ISSN:1932-7447
Publisher DOI:https://doi.org/10.1021/jp502453q

Download

Preview Icon on Download
Preview
Content: Accepted Version
Filetype: PDF
Size: 628kB
View at publisher

TrendTerms

TrendTerms displays relevant terms of the abstract of this publication and related documents on a map. The terms and their relations were extracted from ZORA using word statistics. Their timelines are taken from ZORA as well. The bubble size of a term is proportional to the number of documents where the term occurs. Red, orange, yellow and green colors are used for terms that occur in the current document; red indicates high interlinkedness of a term with other terms, orange, yellow and green decreasing interlinkedness. Blue is used for terms that have a relation with the terms in this document, but occur in other documents.
You can navigate and zoom the map. Mouse-hovering a term displays its timeline, clicking it yields the associated documents.

Author Collaborations