Identification of energy levels of negative ions

Abstract

Levels of He- at 57.1 and 58.2 eV and of Hg- at 4.07, 4.29, and 4.89 eV, whose observation is described in an accompanying paper, are identified spectroscopically as 2s22pP2, 2s2p2D2, 6s6p2P12,32,524, respectively. The identification procedure, which combines elements of spectroscopy and collision theory, is described. © 1965 The American Physical Society.