Effective configurations in electron-molecule scattering. II - art. no. 062703

We present results of the application of the Schwinger multichannel method using effective configurations [Azevedo et al.. Phys. Rev. A 61, 042701 (20 00)] to study special features of low-energy electron-molecule scattering, such as (i) the shape resonance in e(-)-N-2 scattering: (ii) the Ramsauer-T ownsend minimum in e(-)-CH4 scattering: and (iii) a Feshbach resonance in e (-)-H-2 scattering (in a two-channel coupling calculation including polariz ation effects). In all cases, we find that the use of effective configurati ons to describe polarization effects allows a substantial reduction of the configuration spacer without any loss of quality of the results. The presen t applications (together with our previous study of nonresonant electron-H- 2 scattering) indicate that this technique will be very useful in the analy sis of more complex systems.