Extension of the Pt III Analysis

Abstract

Using a sliding spark and a 6.65 m normal incidence vacuum spectrograph, the third spectrum of platinum was analyzed. The transitions involving high-lying levels were studied. A total of 241 Pt III lines of the transitions from the levels of the 5d76p + 5d66s6p configurations in the region 728–2062 Å were classified, increasing the number of known Pt III lines to more than 1000. Ninety-one energy levels belonging mostly to the 5d66s6p configuration were added to Pt III. The odd Pt III levels were theoretically interpreted by means of multiconfiguration Dirak–Fock calculations and a least-squares fit of the calculated to the observed levels in the framework of the orthogonal parameters technique.