Dynamics on Multiple Potential Energy Surfaces: Quantitative Studies of Elementary Processes Relevant to Hypersonics

Area of Science:

• Chemical Physics
• Computational Chemistry
• Aerospace Engineering

Background:

• Hypersonic flight simulations require accurate thermal and vibrational relaxation rates.
• Triatomic systems play a key role in high-temperature gas dynamics.
• Existing computational methods can be resource-intensive.

Purpose of the Study:

• To determine thermal and vibrational relaxation rates for triatomic systems.
• To provide accurate data for hypersonic model calculations.
• To explore efficient computational strategies for these rates.

Main Methods:

• Computing accurate potential energy surfaces for ground and excited electronic states.
• Performing quasiclassical or quantum nuclear dynamics simulations.
• Developing neural network models for computational efficiency.

Main Results:

• Methodology for calculating thermal reaction rates, state-to-state cross sections, and vibrational relaxation rates is presented.
• Exemplary calculations for [NNO], [NOO], and [CNO] systems are described.
• A neural network model for state-to-state cross sections is discussed.

Conclusions:

• The presented methods provide essential data for hypersonic simulations.
• Accurate potential energy surfaces and dynamics simulations are critical.
• Neural network models offer a promising approach to reduce computational cost.