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Updated: Jul 16, 2026

Raman and IR Spectroelectrochemical Methods as Tools to Analyze Conjugated Organic Compounds
Published on: October 12, 2018
Raman spectroscopy as tool for the characterization of thio-polyaromatic hydrocarbons in organic minerals
Otakar Frank1, Jan Jehlicka, Howell G M Edwards
1Institute of Geochemistry, Mineralogy and Mineral Resources, Faculty of Science, Charles University in Prague, Albertov 6, 128 43 Prague 2, Czech Republic. frankota@natur.cuni.cz
Abstract:
Benzothiophene and dibenzothiophene have been studied by Raman microspectroscopy using a 785 nm excitation wavelength. The spectra obtained have been compared with the previously measured spectra of idrialite, a complex natural mineral composed entirely of cata-condensed polyaromatic hydrocarbons (PAHs), usually containing a thiophenic or aliphatic five-membered ring. For comparison, the Raman spectra of 2,3-benzofluorene crystals have been obtained for the first time. Some of the bands in the idrialite spectra are attributed to specific vibrational modes of thiophene or fluorene-type PAHs, especially in the region below 1000 cm(-1). These modes at 495, 705 and 750 cm(-1) along with C-H or C-H(2) stretching modes around 3000 cm(-1) can be then used to distinguish such groups of PAHs in complicated organic mineral mixtures like idrialite.
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