On the accuracy of reactive scattering calculations with absorbing potentials: a new implementation based on a generalized R-matrix propagation

A quantum scattering method based on combining a generalization of the propagative R-matrix technique with negative imaginary potentials is presented. Reactive probabilities are then obtained considering only the reactants arrangement channel and Jacobi coordinates. Collinear and infinite order sudden results are shown for the Cl+HCl symmetric reaction, showing excellent agreement with previous results, including the reproduction of sharp reactive scattering resonances, at a fraction of the computer time and memory requirements.