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Analyzing the Photo-oxidation of 2-propanol at Indoor Air Level Concentrations Using Field Asymmetric Ion Mobility Spectrometry
Published on: June 14, 2018
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Outer Valence Photoionization and Autoionization of Formaldehyde
Kedong Wang1, Yan Wang1, Haiyang Qiao1
1School of Physics, Henan Normal University, Xinxiang 453007, Peoples Republic of China.
The Journal of Physical Chemistry. A
|August 11, 2022
Summary
We studied formaldehyde photoionization using advanced R-matrix calculations. Our results, including resonance structures, agree well with experiments, improving upon previous theoretical models.
Area of Science:
- Quantum chemistry
- Molecular physics
- Spectroscopy
Background:
- Formaldehyde is a key molecule in atmospheric and interstellar chemistry.
- Understanding its photoionization dynamics is crucial for interpreting observational data and atmospheric models.
Purpose of the Study:
- To investigate the photoionization of formaldehyde from its ground electronic state.
- To calculate partial cross sections and asymmetry parameters for various ionic states.
- To explore the impact of electron correlation on photoionization dynamics.
Main Methods:
- Utilized the multichannel R-matrix method incorporating configuration interaction (CI).
- Calculated photoionization properties for photon energies from 10-90 eV.
- Assessed the sensitivity of results to continuum descriptions, partial waves, and active spaces.
Main Results:
- Observed extensive resonance structures near the ionization threshold for the first time.
- Obtained convergent results by carefully checking model sensitivities.
- Predicted total cross sections and asymmetry parameters that differ from previous uncorrelated calculations.
Conclusions:
- The inclusion of electron correlation is vital for accurate formaldehyde photoionization predictions.
- The multichannel R-matrix method with CI provides reliable results.
- The findings align well with available experimental data, validating the theoretical approach.
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