25-STATE CALCULATION FOR E(-)-NA-2 SCATTERING

We use the Schwinger multichannel method with pseudopotentials to stud y low energy e(-)-Na-2 scattering. Our cross sections, for impact ener gies from 0 to 10 eV, include polarization effects and up to 25 open c hannels related to all electronic states lying below 3.5 eV. Our resul ts predict prominent threshold effects due to a very intense coupling between the B(1)Pi(u) state and the elastic channel in an energy regio n where there is no experimental data. Our total 25-state cross sectio ns are in very good agreement with available experimental data for ene rgies below about 4 eV. [S0031-9007(98)07561-9].