Analyses of the 5p65d-(5p66p + 5p65f + 5p55d2) transitions of eight times ionized iridium to eleven times ionized mercury spectra (Ir IX-Hg XII)

The spectra of iridium, platinum, gold and mercury ions were photographed in the 100-300 A region on a variety of grazing incidence spectrographs. The source used in each spectrum was a triggered spark. The 5p65d-(5p6(5f + 6p) + 5p55d2) transitions of the Yb II isoelectronic sequence from Ir IX to Hg XII were analysed. 53 lines in Ir IX, 55 lines in Pt X, 56 lines in Au XI and 56 lines in Hg XII have been classified. Earlier identifications in Ir IX, Pt X, Au XI and Hg XII by Kaufman and Sugar (1976) have been confirmed. The ground state intervals 5p65d2D have been found to be 16 185 cm-1, 19 096 cm-1, 22 255 cm-1 and 25 633 cm-1 respectively for Ir IX-Hg XII. Out of the 42 levels with 0.5 ≤ J ≤ 3.5 of the three odd parity configurations 36 levels in Ir IX, 38 levels in Pt X and 39 levels each in Au XI and Hg XII have been established. Relativistic Hartree-Fock (HFR) and least-square-fitted (LSF) parametric calculations, involving configuration interactions, were carried out to interpret the spectra satisfactorily. (orig.)