Charge transfer in SERS: spectra of 3,5-dimethylpyridine at a silver electrode

✍ Scribed by J. F. Arenas; I. López Tocón; M. S. Woolley; J. C. Otero; J. I. Marcos

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 261 KB
• Volume: 29
• Category: Article
• ISSN: 0377-0486
• DOI: 10.1002/(sici)1097-4555(199808)29:8<673::aid-jrs291>3.0.co;2-v

✦ Synopsis

The SERS spectra of 3,5-dimethylpyridine recorded at di †erent electrode potentials were analysed. Their most characteristic feature is the enhancement of the band assigned to mode 8a as the electrode potential becomes more negative. This behaviour is di †erent to that observed in the SERS spectra of pyridine where all four modes 6a, 1, 9a and 8a are enhanced in spite of the fact that both molecules belong to the same molecular point group. These di †erences were explained on the basis of a resonant charge transfer mechanism (CT). The band assigned to the fundamental was used to estimate the electromagnetic mechanism contributions to SERS intensities, m s (CH 3 ) which allowed the direct correlation of the theoretical SERS-CT intensities calculated on the basis of PeticolasÏ equation with experimental results.