In order to calculate electron scattering cross sections you can use one of the three main ab initio methods are based on:
- Kohn variational principle
- Schwinger variational principle
- R-matrix method
UKRmol and UKRMol+ codes are employing the R-matrix method and the latter can be found free to download on:
https://zenodo.org/record/2630496#.XjBki2j7S70
The codes can also be used within Quantemol-N and Quantemol-EC commercial software packages, which include other methods for a wide range of cross sections calculations.