Gaussian-type-orbital basis sets for the calculation of continuum properties in molecules: The differential photoionization cross section of molecular nitrogen

The differential cross section of the valence one-photon ionization of ${\mathrm{N}}_2$ is computed in the random phase approximation using large $L^2$ basis sets of Gaussian-type orbitals (GTO’s) and a $K$-matrix-based technique. Several special polynomial spherical GTO’s are included in the basis set used to adequately represent the orbitals lying in the electronic continuum. Ionization channels originating from the $3{\sigma }_g,$ $1{\pi }_u,$ $2{\sigma }_u,$ and $2{\sigma }_g$ occupied orbitals are considered, both in separated and interacting channel approaches.