Experimental Investigation of the Hyperfine Structure of Neutral Praseodymium Spectral Lines and Discovery of New Energy Levels

Shamim Khan, Imran Siddiqui, Zaheer Uddin, G. Guthöhrlein, Laurentius Windholz, Syed Tanweer Iqbal

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Experimental investigations of Pr I spectral lines were performed by means of laser induced fluorescence spectroscopy, using a hollow cathode discharge lamp as source of free atoms. The wavelengths for the laser excitation were found by the help of a highly resolved Fourier transform spectrum. Altogether we excited 236 unclassified lines and analysed their hyperfine structure, which led, together with the measured wavelengths of the observed fluorescence lines, to the discovery of 32 new even parity and 38 odd parity fine structure energy levels. These levels allow to classify more than 670 spectral lines of Pr I. The wave number calibrated Fourier transform spectrum allowed us to determine the energies of most of these newly discovered levels with an uncertainty of 0.015 cm-1. Angular momenta, parity, and magnetic and electric hyperfine interaction constants (A and B) of the new levels were also determined.
Original languageEnglish
Pages (from-to)7-29
Number of pages23
JournalInternational journal of quantum chemistry
Issue number1
Publication statusPublished - Jan 2017

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  • Sonstiges

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