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Published on: June 20, 2014
Coupling interactions between sulfurous acid and the hydroperoxyl radical.
Ping Li1, Zhi-Ying Ma, Wei-Hua Wang
1Key Laboratory of Life-Organic Analysis, College of Chemistry Science, Qufu Normal University, Qufu, 273165, P. R. China. lignip@163.com
Summary
This study explores sulfurous acid (H2SO3) and hydroperoxyl radical (HOO) interactions. Two stable complexes with strong hydrogen bonds were identified, crucial for atmospheric chemistry.
Area of Science:
- Atmospheric Chemistry
- Computational Chemistry
- Quantum Chemistry
Background:
- Hydroperoxyl radical (HOO) complexes are vital in atmospheric chemistry.
- Understanding radical-molecule interactions is key to atmospheric processes.
Purpose of the Study:
- Investigate the coupling interactions between sulfurous acid (H2SO3) and the HOO radical.
- Characterize the stability and nature of H2SO3...HOO complexes.
- Provide insights for experimental identification of these complexes.
Main Methods:
- Density Functional Theory (DFT) using B3LYP/6-311++G(3df,3pd).
- Atoms in Molecules (AIM) theory.
- Natural Bond Orbital (NBO) method.
- Energy Decomposition Analyses (EDA).
Main Results:
- Eight stable stationary points identified on the H2SO3...HOO potential energy surface.
- Two most stable complexes exhibit strong, partially covalent double intermolecular hydrogen bonds.
- Binding energies for the most stable complexes are -12.27 and -11.72 kcal mol(-1).
Conclusions:
- Sulfurous acid and hydroperoxyl radical form stable complexes with significant intermolecular hydrogen bonding.
- The findings contribute to understanding atmospheric radical chemistry.
- Predicted IR spectra can aid experimental verification.
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