Exchange in low-energy e-CO2 collisions

The validity of three approximate treatments of the exchange interaction in low-energy e-CO2 scattering is assessed by comparing approximate and exact static-exchange eigenphase sums in the resonant Pi/sub u/ symmetry and the nonresonant Σ/sub g/ and Σ/sub u/ symmetries. Of the approximations studied: orthogonalized static, free-electron-gas model potential, and orthogonalized model potential: the latter has yielded results in best agreement with those of the exact treatment of exchange. Newly calculated static-exchange-polarization cross sections for energies from 0.1 to 2.0 eV are presented