AVVISO DI SEMINARIO

Prof. Zahra Jamshidi

 (Department of Physical Chemistry, Chemistry and Chemical Engineering Research Center of Iran
Tehran, Iran)

Surface-Enhanced Raman Spectroscopy: Charge-Transfer Selection Rules

Surface-enhanced Raman scattering (SERS) is one of the most sensitive spectroscopic techniques with a wide range of applications. The charge-transfer SERS as represents the properties of combined system is an important phenomenon and a topic of great studies. The recognition of charge-transfer (CT) resonance selection rule is a difficult task due to the various factors that affect this process. It is known that the energies and electronic structure properties of CT-states can be influenced by the chemical nature of the surface and also the electronic potential of the interface. In our studies, the quantum mechanical calculations elucidated the mechanism of CT and the source of each factor that controls this process. The effect of electrode potential on the SERS spectra of Pyridine and other benzene-derivative compounds which adsorb on the silver cluster has been modelled by means of the excited-state gradient approximation and provided a satisfactory agreement with the experimental studies. We anticipate this kind of investigations would make SERS spectroscopy as a powerful technique for single-molecule detection and shed light on the charge-transfer selection rules.