Transport properties for systems with deep potential wells: H + O2

Area of Science:

• Physical Chemistry
• Chemical Physics
• Quantum Mechanics

Background:

• Understanding the interaction between oxygen (O2) and hydrogen (H) is crucial for various chemical processes.
• Accurate calculation of transport properties requires detailed knowledge of the underlying potential energy surfaces (PESs).

Purpose of the Study:

• To compute the transport properties for collisions between oxygen molecules and hydrogen atoms.
• To utilize quantum scattering calculations for high-fidelity results.
• To investigate the influence of different potential energy surfaces on collision outcomes.

Main Methods:

• Quantum scattering calculations were performed for O2-H collisions.
• Two potential energy surfaces (2A″ and 4A″) were employed.
• A coupled-cluster method was used to compute the 4A″ PES, while an existing PES was used for the 2A″ state. Statistical capture boundary conditions were applied for the 2A″ state.

Main Results:

• Collision integrals were computed for both the 2A″ and 4A″ states.
• The results from both PESs were averaged, weighted by their respective spin multiplicities, to provide a comprehensive transport property dataset.
• The application of statistical capture boundary conditions was essential for accurately modeling the 2A″ state due to its deep potential well.

Conclusions:

• The study provides accurate transport properties for oxygen-hydrogen collisions.
• The methodology accounts for the complexities arising from multiple potential energy surfaces.
• These findings contribute to a better understanding of reactive and non-reactive collisions in such systems.