Calculation of ionization energies, electron affinities, electronegativities, and hardnesses using density functional methods

The performance of two exact exchange methods is tested in the calculation of ionization energies, electron affinities, electronegativities, and hardnesses using Dunning’s correlation consistent basis sets. Comparison is made to experiment and other density functional methods, including the local density approximation and two gradient corrected functionals. The obtained electronegativities and hardnesses are also compared with high level coupled cluster results. Both the exact exchange methods show an excellent performance in the calculation of all four properties, yielding mean absolute deviations from experiment below 0.20 eV for all basis sets.