Translational Energy Influence on a Chemical Laser

A comprehensive Quasi-Classical Trajectory (QCT) investigation is reported for the hydrogen-abstraction reaction, OH (ν = 0, j = 2) + D2 (ν = 0, j = 2) → HOD* + D, aimed at clarifying the mechanisms of energy and angular-momentum disposal in the excited product molecule, HOD*. Calculations were performed on the Wu–Schatz–Lendvay–Fang–Harding (WSLFH) potential energy surface for five collision energies, ET = 0.28–0.64 eV. Vibrational and rotational Gaussian Binning (V-GB and R-GB) methods were applied to obtain state-resolved distributions of the relative translational energy, P(ET′), and internal angular momentum, P(J′), of HOD*. The results show pronounced mode selectivity, with dominant excitation of the OD-stretch vibration at low collision energies, characteristic of an early-barrier abstraction mechanism. Increasing ET promotes a gradual transfer of energy into translational and rotational motion, leading to broader and less anisotropic P(J′) distributions. The combined V-GB and R-GB analysis provides a consistent description of the coupling between translational, vibrational, and rotational degrees of freedom. These findings provide further insight into rovibrational energy partitioning in the OH + D2 reaction and may contribute to the fundamental assessment of this system as a possible source of rovibrationally excited molecules for chemical-laser schemes.