Abstract
Cyanide adsorption in air on silver, gold, and overlayers of gold on silver and silver on gold is investigated by surface enhanced Raman scattering, using island films to enhance the CN Raman scattering by ∼4 orders of magnitude. We studied pure metal island films as well as either silver or gold islands coated with the other metal with overlayer thicknesses ranging from 0.2 to 4 monolayers (Ml). We studied the coverage dependence of the cyanide adsorption for CN coverages ranging from 0.01 to ∼1 Ml. The Raman spectra reveal both considerable adsorption similarities and noteworthy differences for CN adsorption on the pure metals as compared to the overlayers. The spectra also reveal the order of adsorption of the CN into various possible sites, including the substrate metal sites. For each substrate system studied, we find two new distinct linear, on-top CN species adsorbed to two different types of surface site. The harmonic force constants and vibrational modes of the chemisorbed CN differ substantially on silver and gold, and are yet again different for the thin overlayer systems, due to the incomplete buildup of the overlayer three dimensional band structure.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 573-584 |
| Number of pages | 12 |
| Journal | The Journal of chemical physics |
| Volume | 85 |
| Issue number | 1 |
| DOIs | |
| State | Published - 1986 |
| Externally published | Yes |
ASJC Scopus subject areas
- General Physics and Astronomy
- Physical and Theoretical Chemistry