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Updated: Jun 28, 2026

Raman and IR Spectroelectrochemical Methods as Tools to Analyze Conjugated Organic Compounds
Published on: October 12, 2018
Etude par spectroscopie raman du chlorhydrate de cocaine
A P Gamot1, G Vergoten, G Fleury
1Laboratoires de Chimie Analytique et de , Universitéde Lille II, rue du Professeur Laguesse, 59045 Lillem, Lille, France; Centre de Technologie Biomédicale INSERM, 13-17, rue C. Guérin, 59000 Lille, France.
Abstract:
Raman spectra of cocaine hydrochloride in the polycrystalline state and in saturated aqueous solutions have been recorded at room temperature from 0 to 4000 cm(-1) and at 9 K from 0 to 200 cm(-1) (only for the polycrystalline state). They show that cocaine can be characterized by the following proposed assignments. For the tropane nucleus the frequencies 851 and 786 cm(-1) (piperidine) and 896, 870 cm(-1) (pyrrolidine); these frequencies are assigned to ring carbon stretching vibrations V(C-C) Bands for the ester functional groups can be observed at 1713 cm(-1) (v(CO)) and 1203 cm(-1) (v((C-O-O)). The benzene nucleus is also important in characterization of cocaine hydrochloride because of its bands at 616, 990, 1000, 1026 and 1596 cm(-1). Special reference is made first to the work in the low-frequency range at room temperature and 9 K and secondly to the polarization studies of saturated aqueous solutions in the range 700-1726 cm(-1). The results constitute a pool of analytical characteristics which can be used for toxicological investigations, and also show all the possibilities of Raman spectroscopy in this field.
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