Accession Number:

ADA160033

Title:

Surface-Enhanced Raman Spectroscopy as a Probe of Adsorbate-Surface Bonding: Simple Alkenes and Alkynes Adsorbed at Gold Electrodes

Descriptive Note:

Technical rept.

Corporate Author:

PURDUE UNIV LAFAYETTE IN DEPT OF CHEMISTRY

Personal Author(s):

Report Date:

1985-08-01

Pagination or Media Count:

31.0

Abstract:

The interaction of various alkenes with gold electrodes has been studied using surface-enhanced Raman spectroscopy SERS. Large decreases, from 70 to 140cm, were observed in the C-C double bond and C triple bond C stretching frequencies upon adsorption which are attributed to adsorbate-surface bonding involving these groups. The potential dependence of these SERS frequencies suggests that the Pi yield s sigma band overlap is more prevalent than the d yields pi pi bond interaction. Carbon-hydrogen stretching vibrations, nuC-H, as well as other skeletal modes were also detected for the adsorbates paraffinic, olefinic, and aromatic nuC-H modes could readily be distinguished although acetylenic nuCH modes were too weak to be detected. Generally, the most intense SERS bands relative to those in the bulk-phase spectra are associated with vibrations of the carbon-carbon double or triple bonds. Attempts to examine SERS of adsorbated acetylene were thwarted by a spontaneous surface reaction yielding a film of polyacetylene.

Subject Categories:

  • Atomic and Molecular Physics and Spectroscopy

Distribution Statement:

APPROVED FOR PUBLIC RELEASE