Accurate time dependent wave packet calculations for the N + OH reaction

Area of Science:

• Chemical Kinetics
• Quantum Dynamics
• Theoretical Chemistry

Background:

• The N + OH reaction is crucial in atmospheric and combustion chemistry.
• Accurate theoretical calculations are needed to understand reaction dynamics.

Purpose of the Study:

• To perform accurate quantum calculations of state-to-state cross sections for the N + OH → NO + H reaction.
• To compare wave packet calculations with time-independent quantum mechanical and quasi-classical trajectory results.
• To investigate the reaction dynamics over a range of collision energies.

Main Methods:

• Quantum wave packet calculations on the ground (3)A'' adiabatic potential energy surface.
• Calculations performed for selected total angular momentum (J) and helicity components (Ω).
• Analysis of reaction probabilities, cross sections, rate constants, and opacity functions.

Main Results:

• Converged integral state-to-state cross sections obtained up to 0.5 eV collision energy.
• Rate constant for OH(ν = 0, j = 0) agrees well with previous theoretical values.
• Disagreement observed between calculated and experimental rate constants, except at 300 K.

Conclusions:

• The study provides accurate quantum mechanical data for the N + OH reaction.
• Discrepancies with experimental data highlight the need for further investigation.
• The employed theoretical methods are validated against other computational approaches.