Eighth spectrum of iodine: I viii

The eighth spectrum of iodine was photographed in the 1800–310-Å region on 3- and 6.65-m normal-incidence spectrographs. The sources used were a triggered spark and a sliding spark. On the basis of the new measurements, all levels of the 4d10, 4d95s, and 4d95p configurations of I viii have been established. Least-squares-fitted parametric calculations support the analysis. Thirty lines have been classified in this spectrum. Some J = 1 levels of the 4d9np and 4d9nf configurations have been confirmed and extended. The value of the ionization limit of I viii has been calculated at 1220 000 cm−1 (151 eV).