ANALYSES OF THE 5P(6)5D-(5P(6)6P-IX HG-XII)(5P(6)5F+5P(5)5D(2)) TRANSITIONS OF 8 TIMES IONIZED IRIDIUM TO 11 TIMES IONIZED MERCURY SPECTRA (IR)

The spectra of iridium, platinum, gold and mercury ions were photograp hed in the 100-300 Angstrom region on a variety of grazing incidence s pectrographs. The source used in each spectrum was a triggered spark. The 5p(6)5d-(5p(6)(5f + 6p) + 5p(5)5d(2)) transitions of the Yb II iso electronic 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 b een classified. Earlier identifications in Ir IX Pt X, Au XI and Hg XI I by Kaufman and Sugar (J. Opt. Sec. Am. 66, 1019, 1976) have been con firmed. The ground state intervals 5p(6)5d(2)D have been found to be 1 6 185 cm(-1), 19 096 cm(-1), 22 255 cm(-1) and 25 633 cm(-1) respectiv ely for Ir IX-Hg XII. Out of the 42 levels with 0.5 less than or equal to J less than or equal to 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 leas t-square-fitted (LSF) parametric calculations, involving configuration interactions, were carried out to interpret the spectra satisfactoril y.