Surface‐enhanced Raman spectroscopy of 1H‐1,2,3‐triazolo[4,5‐b]pyridine on silver sols

Abstract

AbstractThe surface‐enhanced Raman (SER) spectra of 1H‐1,2,3‐triazolo[4,5‐b]pyridine adsorbed on silver hydrosols were recorded in the region 3500–100 cm−1. From the comparison of the SER and normal Raman spectra of 1H‐1,2,3‐triazolo[4,5‐b]pyridine both in the pure form and dissolved in alkaline solution, it can be deduced that the substance is dissociatively adsorbed on metal surface. In order to interpret the SER spectra, ab initio RHF calculations with a 6–31+G** basis set were performed to obtain the wavenumbers of the vibrational modes of the substance in the anionic form. Considering the relative enhancements of the Raman bands, on the basis of the description of normal modes given by the potential energy distribution it can be concluded that it interacts with silver sol essentially via the lone pairs of the nitrogen atoms, of both the pyridine and triazole rings, the ring π‐system playing a minor role, with a tilted orientation of the molecular plane with respect to the silver surface. Copyright © 2001 John Wiley & Sons, Ltd.