Vibrational spectroscopy of perfluorocarboxylic acids from the infrared to the visible regions.
We report here the gas-phase mid-IR, near-IR, and visible vibrational spectra of perfluoropropionic, perfluorooctanoic, and perfluorononanoic acids using Fourier transform and cavity ring-down spectroscopy. The impetus for this work was to provide insight into the behavior of environmentally persistent perfluorocarboxylic acids. Although the most intense transition for all three perfluorocarboxylic acids in the fundamental spectra is the CF3 stretch, the O-H stretch carries the most intensity in the overtone region. We record the O-H stretching transition frequencies and absorption cross-sections in the DeltavOH = 1-5 regions. Our work suggests that perfluorocarboxylic acids have more harmonic O-H bonds, smaller transition frequencies, and smaller intensities as compared to shorter-chain hydrocarbon acids, alcohols, and peroxides.
Rontu
Nabilah
N
Department of Chemistry and Biochemistry and CIRES, Campus Box 215, University of Colorado, Boulder, Colorado 80309, USA.
Vaida
Veronica
V
D002264:Carboxylic Acids / Q000737:chemistry*; D017611:Fluorine Compounds / Q000737:chemistry*; D006859:Hydrogen / Q000737:chemistry; D010100:Oxygen / Q000737:chemistry; D013055:Spectrophotometry, Infrared; D013696:Temperature; D014732:Vibration
D002264:Carboxylic Acids; D017611:Fluorine Compounds; D006859:Hydrogen; D010100:Oxygen