A simple potential for low-energy s-wave scattering of electrons from closed-shell atoms

A simple potential is proposed to describe low-energy s-wave scattering of electrons from closed-shell atoms. It has the correct structure at large and small distances from the nucleus and depends on the target polarizability and a dimensionless parameter. This dimensionless parameter is determined by extrapolation from the potential for the bound states in isoelectronic sequences. Apart from providing a satisfactory description of low-energy scattering of electrons from inert-gas atoms, the potential predicts a negative scattering length for electron scattering from Be, Mg, Zn, Cd, Hg, and zeros in the s-wave phase shin at a momentum k in the range 0.05-0.10 au