Calculation of temporary anion states using density functional theory Original Research Article

Density functional theory (DFT) was examined for computing energies of temporary anions having negative electron affinities ranging from −8.0 to −0.2 eV. The calculated electron affinities are in good agreement with experiment for π∗ states and low-energy σ∗ states. The dependence of the DFT results on basis set was investigated. Comparisons are made with results from traditional ab initio molecular orbital theory based on Koopmansʹ theorem (KT) and energy difference methods (ΔHF and ΔMP2). It is shown that DFT methods provide an improvement over use of ab initio molecular orbital methods.