| Title: | Separation of Electromagnetic and Chemical Contributions to Surface-Enhanced Raman Spectra on Nanoengineered Plasmonic Substrates |
| Author: |
Saikin, Semion K.; Chu, Yizhuo; Rappoport, Dmitrij; Crozier, Kenneth B.; Aspuru-Guzik, Alán
Note: Order does not necessarily reflect citation order of authors. |
| Citation: | Saikin, Semion K., Yizhuo Chu, Dmitrij Rappoport, Kenneth B. Crozier, and Alán Aspuru-Guzik. 2010. Separation of electromagnetic and chemical contributions to surface-enhanced Raman spectra on nanoengineered plasmonic substrates. Journal of Physical Chemistry Letters 1(18): 2740–2746. |
| Full Text & Related Files: |
Separation_of_electromagnetic_and_chemical.pdf (746.2Kb; PDF)
|
| Abstract: | Raman signals from molecules adsorbed on a noble metal surface are enhanced by many orders of magnitude due to the plasmon resonances of the substrate. Additionally, the enhanced spectra are modified compared to the spectra of neat molecules; many vibrational frequencies are shifted, and relative intensities undergo significant changes upon attachment to the metal. With the goal of devising an effective scheme for separating the electromagnetic and chemical effects, we explore the origin of the Raman spectra modification of benzenethiol adsorbed on nanostructured gold surfaces. The spectral modifications are attributed to the frequency dependence of the electromagnetic enhancement and to the effect of chemical binding. The latter contribution can be reproduced computationally using molecule−metal cluster models. We present evidence that the effect of chemical binding is mostly due to changes in the electronic structure of the molecule rather than to the fixed orientation of molecules relative to the substrate. |
| Published Version: | doi:10.1021/jz1008714 |
| Terms of Use: | This article is made available under the terms and conditions applicable to Open Access Policy Articles, as set forth at http://nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of-use#OAP |
| Citable link to this page: | http://nrs.harvard.edu/urn-3:HUL.InstRepos:8347335 |
Contact administrator regarding this item (to report mistakes or request changes)