Extension of the Launay Quantum Reactive Scattering Code and Direct Computation of Time Delays

Area of Science:

• Molecular Physics
• Quantum Chemistry
• Chemical Dynamics

Background:

• Scattering computations are vital for understanding molecular dynamics.
• Analyzing collision duration and intermediate complex lifetimes provides key insights.
• Powerful quantum methods have advanced the study of these processes.

Purpose of the Study:

• To extend the HYP3D code for molecular reactive scattering calculations.
• To develop a method for computing the Smith matrix (Q) without numerical differentiation of the scattering matrix (S).
• To calculate lifetimes of metastable intermediate ozone complexes.

Main Methods:

• Utilized the Smith matrix (Q) derived from the scattering matrix (S) and its energy derivative.
• Extended the Launay HYP3D code for reactive scattering.
• Employed an extended Johnson-Manolopoulos integration for wave function propagation.
• Calculated the Q matrix from the wave function, avoiding numerical S matrix differentiation.

Main Results:

• Successfully computed the Q matrix for molecular reactive scattering.
• Calculated lifetimes for the metastable intermediate ozone complex (O3*).
• Results for the oxygen exchange reaction align with previous studies for zero total angular momentum.

Conclusions:

• The extended HYP3D code provides a robust method for calculating molecular collision dynamics.
• The new approach accurately determines metastable state lifetimes.
• This work offers a benchmark for future studies on ozone chemistry and mass-independent fractionation.