Density functional theory calculation of K-shell excitation of nitrous oxide

The inner-shell excitation of N2O is studied with DFT. Choice of functional and basis set affects the accuracy. In this work, we employ a basis of augmented even-tempered valence quadruple-zeta basis of Slater-type orbitals. For the excitation energies, we use our approximation of ΔE(PW86-PW91), plus small relativistic correction; and, for estimation of relative intensities, we use time-dependent DFT. The results confirm the earlier conclusion that ΔE(PW86-PW91) can give quite reliable excitation energies. The average absolute deviation of 11 calculated excitations from experiment is only 0.26 eV. The quality of the f-values is harder to judge because of experimental difficulties.