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Published on: March 24, 2018
The nu5 Band of HClO4
Journal of Molecular Spectroscopy
|December 16, 1998
Summary
High-resolution infrared spectroscopy of perchloric acid (HClO4) reveals its HO-ClO3 stretch. This data aids in identifying atmospheric HClO4, potentially formed from stratospheric chlorine oxidation.
Area of Science:
- Molecular Spectroscopy
- Atmospheric Chemistry
Background:
- Perchloric acid (HClO4) is a molecule of interest in atmospheric chemistry.
- Understanding its spectral properties is crucial for atmospheric detection and source attribution.
Purpose of the Study:
- To obtain high-resolution infrared spectra of perchloric acid.
- To assign spectral features to specific molecular vibrations.
- To provide data for atmospheric identification of HClO4.
Main Methods:
- Utilized the infrared beamline at the MAX-I electron storage ring.
- Observed the spectrum in the 700-750 cm-1 region.
- Performed single subband analysis to fit spectral transitions.
Main Results:
- Observed extensive rotational structure assigned to the nu5 (HO-ClO3 stretch) band.
- Fitted approximately 1100 transitions for H35ClO4 and 300 for H37ClO4.
- Determined the origin of the H35ClO4 K = 3t series to be 726.9971(4) cm-1.
Conclusions:
- Rotationally resolved infrared line positions for HClO4 are now available.
- This spectral data facilitates the identification of HClO4 in the atmosphere.
- Atmospheric HClO4 may originate from heterogeneous oxidation of stratospheric chlorine species.
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