The results obtained on the W VIII spectrum as well as on the isoelectronic spectra Lu V, Hf VI, Ta VII, and Re IX in the VUV wavelength region are summarized with emphasis on the main trends along the isoelectronic sequence. A total of 187 lines of W VIII in the region of 160–271 Å were accurately measured and identified, 98 levels were found, and transition probabilities calculated. The isoelectronic regularities support the data on W VIII. A list of spectral lines in the region of 170–199 Å, considered as belonging to W IX, is presented.

The spectrum of silver, excited in a vacuum spark, was recorded in the region 150–350 Å on a 3-m grazing incidence spectrograph. The resonance 4d^k–(4d^k−15p + 4d^k−14f + 4p⁵4d^k+1) was studied in the Ag⁶⁺–Ag⁸⁺ spectra (Ag VII–Ag IX) with k = 5–3, respectively. Several hundred lines were identified with the aid of the Cowan code and orthogonal operator technique calculations. The energy levels were found and the transition probabilities were calculated.

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The spectrum of tin, excited in a vacuum spark, was recorded in the region 500–1131 Å on a 6.65-m normal incidence spectrograph. The transitions between 4d⁸5s, 4d⁸6s, 4d⁸5p and 4d⁸5d excited configurations in Sn VI were studied. More than 500 lines of the 4d⁸5p–4d⁸5d and 4d⁸5p–4d⁸6s were identified with the aid of the Cowan code calculations. 67 energy levels (out of 70 possible levels of the 4d⁸5d configuration) and all but two 4d⁸6s levels were found. The wavelength of the 4d⁸5s–4d⁸5p transitions in the region 839–1131 Å were re-measured and supplemented by Sn VI lines in the region 1131–1300 Å measured previously by Srivastava et al. (1977) for optimisation of the energy level values. The SnVI line list in the region 500–1300 Å contains now 741 lines with calculated transition probabilities.