e-HCl and e-HBr scattering calculations in the valence space

The ability of the current effective core potentials of quantum chemistry to account for the scattering properties of molecules is studied in the test cases of e-HCl and e-HBr elastic scattering. Unexpected problems show up when using most recently published potentials. A single effective potential is able to compete with the all-electron methods in terms of accuracy. The associated reduction of computer time makes it highly desirable to overcome the few difficulties outlined in the present work.