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Published on: May 21, 2019
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Photoionization Efficiencies of Five Polycyclic Aromatic Hydrocarbons
K Olof Johansson1, Matthew F Campbell1, Paolo Elvati2
1Combustion Research Facility, Sandia National Laboratories , Livermore, California 94550, United States.
The Journal of Physical Chemistry. A
|May 19, 2017
Summary
Researchers measured photoionization cross-sections for polycyclic aromatic hydrocarbons like pyrene using vacuum ultraviolet radiation. These findings provide crucial data for understanding these molecules
Area of Science:
- Physical Chemistry
- Atomic and Molecular Physics
- Spectroscopy
Background:
- Polycyclic Aromatic Hydrocarbons (PAHs) are significant in astrochemistry and combustion.
- Accurate photoionization cross-section data is vital for quantitative analysis.
- Previous data for these specific PAHs in the VUV range is limited.
Purpose of the Study:
- To measure photoionization efficiency curves for pyrene, fluoranthene, chrysene, perylene, and coronene.
- To derive photoionization cross-section curves for these PAHs.
- To provide benchmark data in the 7.5-10.2 eV photon energy range.
Main Methods:
- Utilized tunable vacuum ultraviolet (VUV) radiation from a synchrotron source.
- Employed time-of-flight mass spectrometry for detection.
- Used 2,5-dimethylfuran as an in-situ flux calibration standard.
Main Results:
- Successfully obtained photoionization efficiency curves for the target PAHs.
- Derived photoionization cross-section curves within the specified VUV energy range.
- Demonstrated the utility of 2,5-dimethylfuran for accurate photon flux determination.
Conclusions:
- The study presents novel photoionization cross-section data for key PAHs.
- This data enhances the quantitative interpretation of VUV spectroscopic measurements.
- Findings contribute to atmospheric and combustion chemistry research.
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