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Formic acid aggregation in 2D supersonic expansions probed by FTIR imaging.
Katharina A E Meyer1, Martin A Suhm1
1Institut für Physikalische Chemie, Universität Göttingen, Tammannstr. 6, 37077 Göttingen, Germany.
The Journal of Chemical Physics
|October 17, 2017
Summary
Formic acid trimers' C=O stretching vibrations were identified using FTIR and Raman jet spectroscopy. Shock waves
Area of Science:
- Molecular spectroscopy
- Physical chemistry
- Supersonic jet expansions
Background:
- Formic acid is a fundamental molecule in atmospheric and biological systems.
- Understanding molecular clusters and their behavior is crucial for various scientific fields.
- Supersonic jet expansions are key for studying weakly bound molecular systems under controlled conditions.
Purpose of the Study:
- To assign C=O stretching vibrations of formic acid trimers.
- To investigate the influence of shock waves on molecular cluster formation and decomposition.
- To develop and utilize advanced spectroscopic techniques for cluster analysis.
Main Methods:
- Fourier Transform Infrared (FTIR) and Raman jet spectroscopy were employed.
- FTIR imaging was used to validate spectral assignments based on aggregation.
- A double slit nozzle was developed to merge supersonic jets for localized shock wave studies.
Main Results:
- Specific C=O stretching vibrations for formic acid trimers were successfully assigned.
- The impact of shock waves on the formation and dissociation of formic acid clusters was observed.
- The double slit nozzle enabled a more focused examination of shock wave phenomena.
Conclusions:
- The study provides detailed vibrational assignments for formic acid trimers.
- Shock waves significantly influence the dynamics of molecular clusters in supersonic expansions.
- The developed methodology allows for precise investigation of shock wave effects on molecular systems.
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