The Spectrum of Doubly Ionized Titanium, Ti III

Abstract

The Ca I-like spectrum of titanium, Ti III, has been investigated by means of a pulsed hollow-cathode discharge. A total of 724 lines, covering the region from 630 to 9 300 Å, have been observed and classified, 597 of which lie above 2 000 Å. Practically all levels of the following configurations have been found: 3 d 4 s , 5 s , 6 s ; 4 s 2 ; 3 d 4 p , 5 p ; 4 s 4 p ; 3 d 2 ; 3 d 4 d , 5 d ; 3 d 4 f , 5 f ; 3 d 5 g , 6 g ; 3 d 6 h . They exhibit a variety of different coupling cases and some interesting cases of configuration interaction. The series limit has been determined by applying the polarization formula to 5 g , 6 g and 6 h , giving an ionization energy of 221 735.6±2 cm -1 .