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: 3d4s, 5s, 6s; 4s 2; 3d4p, 5p; 4s4p; 3d 2; 3d4d, 5d; 3d4f, 5f; 3d5g, 6g; 3d6h. 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 5g, 6g and 6h, giving an ionization energy of 221 735.6±2 cm-1.