The First Spark Spectrum of Manganese

Abstract

The analysis of the Mn II spectrum has been extended to include a classification of over seven hundred lines arising from combinations between terms belonging to the quintet and septet systems. From four members of the $3d^5\left({}_{}{}^6{}_{}{}^{}S\right)n{f}^{7}f$ series an ionization potential of 126,147 wave numbers has been calculated by means of a Ritz formula. Pictures have been taken and measurements made covering the range from approximately 800A to 6000A. A hollow cathode discharge was used as a source, with each of the three gases, helium, argon and neon, as conducting media.