Quantum Mechanical Calculations of Vibrational Population Inversion in Chemical Reactions: Numerically ExactL2-Amplitude-Density Study of theH2Br Reactive System

Numerically exact, fully three-dimensional quantum mechanical reactive scattering calculations are reported for the ${\mathrm{H}}_2$Br system. Both the exchange (H + H′Br→ H′ + HBr) and abstraction (H + HBR→ ${\mathrm{H}}_2$ + Br) reaction channels are included in the calculations. The present results are the first completely converged three-dimensional quantum calculations for a system involving a highly exoergic reaction channel (the abstraction process). It is found that the production of vibrationally hot ${\mathrm{H}}_2$ in the abstraction reaction, and hence the extent of population inversion in the products, is a sensitive function of initial HBr rotational state and collision energy.