Open AccessThe spectra of trebly-ionised oxygen (O IV) and trebly-ionised nitrogen (N IV)
Publication year - 1930
Publication title -
proceedings of the royal society of london. series a, containing papers of a mathematical and physical character
Language(s) - English
Resource type - Journals
eISSN - 2053-9150
pISSN - 0950-1207
DOI - 10.1098/rspa.1930.0061
Subject(s) - spectral line , oxygen , extrapolation , nitrogen , oxygen atom , ultra violet , analytical chemistry (journal) , spectrum (functional analysis) , physics , atomic physics , chemistry , mathematics , molecule , chromatography , quantum mechanics , mathematical analysis , optoelectronics
The spectrum of trebly-ionised oxygen has been investigated in the extreme ultra-violet by Bowen, who has identified five of the deepest doublet terms, namely 2p 2 P, 2p' 2 S, 2p' 2 P, 2p' 2 D and 2p 3 2 P. A list of 76 lines in the near ultra-violet, attributed to O IV, was given by Mihul, but no classifications were made. The present paper deals mainly with the identification of the 3s 2 S, 3p 2 P, 3d 2 D terms of the doublet system, and of the 3s' , 3p' and 3d' terms of the quartet system from their combinations occurring in the visible and near ultra-violet regions. The spectrum has been photographed on various instruments from λ 7000 to λ 1250 by using strongly condensed discharges in vacuum tubes containing oxygen. The detection of some of the fainter multiplets was greatly facilitated by the prediction of their positions by extrapolation from corresponding multiplets in C II and N III. As the region investigated is rich in lines of O II and O III, there are many instances of O IV lines being masked by lines of O II and O III.