Spectrum of doubly ionized neon

The spectrum of doubly ionized neon (Nei i i), emitted from hollow-cathode and θ-pinch discharges, has been photographically recorded in the 430–12 000-Å wavelength range. The number of classified lines has been increased from about 100 to about 750, and the number of experimentally established energy levels from 60 to 230. The level scheme comprises levels in the 2${\mathit{s}}^2$2${\mathit{p}}^4$, 2s2${\mathit{p}}^5$, 2${\mathit{p}}^6$, 2${\mathit{s}}^2$2${\mathit{p}}^3$3s-8s, 3p-5p, 3d-5d, 4f-8f, and 5g-7g configurations. The experimentally observed level distributions are compared with the results of Hartree-Fock calculations and least-squares fits.