Negative imaginary potential to model ionization in atoms and molecules by electron impact

The low-energy electron-molecule collisions have several implications for the behavior of microscopic and macroscopic environments. One of the most important consequences of this event is molecular ionization due to the electron impact. Since the inclusion of ionization effects through ab initio methods is challenging, we implemented a negative imaginary potential to act as a sinkhole of probability flux to mimic the ionization effects in electron-molecule collisions. We employed an iterative procedure to reproduce the total ionization cross sections computed with the binary-encounter-Bethe model and investigated some Gaussian distributions representing the model potential. Also, in light of obtaining a model with a reasonable physical significance and avoiding arbitrariness, we performed calculations using the probability density as an imaginary potential. Our main goal is to investigate the effect of an absorption potential in the elastic and inelastic channels in ab initio calculations using the Schwinger multichannel method. The results obtained in this study using ${\mathrm{H}}_{2}$ as a test case are encouraging, since the absorption channel disputes flux probability with other channels.