Comparative study of low-energyΣg+2andΠg2scattering in molecular nitrogen

The linear-algebraic—optical-potential method is applied to low-energy ${}_{}{}^2{}_{}{}^{}\Sigma _g^{+}{}_{}{}^{}$ and ${}_{}{}^2{}_{}{}^{}\Pi _g^{}{}_{}{}^{}e+{\mathrm{N}}_2$ scattering in order to understand the nature of the correlation effects in these two symmetries. The calculations clearly show that the two symmetries are dominated by quite different physical effects. The ${}_{}{}^2{}_{}{}^{}\Sigma _g^{+}{}_{}{}^{}$ scattering is sensitive to long-range dipole distortions of the ${\mathrm{N}}_2$ core, while ${}_{}{}^2{}_{}{}^{}\Pi _g^{}{}_{}{}^{}$ symmetry is critically dependent on short-range correlations which conserve the ${\Sigma }_g^{+}$ symmetry of the ${\mathrm{N}}_2$ core electrons. Quantitative results which support these conclusions are presented and implications of the calculations on the construction and use of model potentials and polarized orbitals are briefly discussed.