Coherent Anti-Stokes Raman Spectroscopy of Commercial Oil Samples

Abstract

Three commercial oil samples were analyzed with the use of the selectivity of resonance CARS. No fractionation procedures were used; the oil samples were simply dissolved in an appropriate solvent and pumped from 365 nm to 480 nm. All three samples could be differentiated by characteristic Raman bands at various pump wavelengths. In addition, comparisons between the CARS spectra of the oil samples and the CARS spectra of pure PAHs at the same pump wavelength yielded tentative identifications of perylene and benzo(ghi)perylene in two of the samples.

Chapter 4. Raman spectroscopy

“…Temperature can be determined for a variety of systems, including a~etylene,'~~ sooting flames,'97 supersonic jets,19* furnaces,lW and temperature distributions round incandescent filaments.2oo CARS has also been applied to catalytic reactors where axial methane concentrations have been measured in the catalytic tube-wall reactor.201 Another application reported is the quantiative determination of individual polycyclic aromatic hydrocarbons in mixtures. 202 One of the little used non-linear techniques, Raman induced Kerr effect spectroscopy (RIKES), has been used successfully to obtain Raman spectra of highly fluorescent material^,^^ and it could well be that this technique will be applicable where other fluorescence rejection methods are not appropriate. If, for example, it proves to be possible to obtain spectra by RIKES of very dark coloured fluorescent liquids it may prove to be a more suitable technique than Fourier transform Raman spectroscopy for this type of material.…”

Raman spectroscopy

“…The technique has also been used to study van der Waals complexes, eg. carbon dioxide dimer (465) and to make quantitative measurements of individual polycyclic aromatic hydrocarbons in mixtures (466).…”

Raman spectroscopy

“…CARS has also been used in the study of excited states of metalloporphyrins (392), of polycyclic aromatic hydrocarbons (393), of commercial oil samples (394), and of radical reactions (395). Coal gasification streams have been analyzed (396), and surface-enhanced CARS has been observed when the active molecules are located near the surface of a small silver particle (397).…”