The Spectrum of Five Times Ionized Fluorine

The F VI spectrum in the 400-6000 Å region has been obtained through the beam-foil excitation technique. In this wavelength interval 177 F VI lines have been observed. With the addition of 123 lines below 200 Å from un unpublished analysis by Edlén, 158 energy levels have been established. Using polarization formulae the first ionization limit is determined to 1267606 ± 2 cm-1, and all available experimental polarization parameters in the Be sequence are collected and compared to theoretical calculations. Some of the strong configuration interactions in the F VI term system are studied by comparing the experimental results with theoretical predictions obtained in single- and multi-configuration calculations.