Term Values in the Arc Spectrum of Selenium

A number of new lines in the spectrum of Se I have been observed and classified, and term values are given with respect to the lowest level of Se II, $4p^3{}_{}{}^4{}_{}{}^{}S$. The first ionizing potential of the selenium atom in its lowest energy state ($4p^4{}_{}{}^3{}_{}{}^{}P_2^{}{}_{}{}^{}$) is 78,659 ±2 ${\mathrm{cm}}^{-1\mathrm{}}$ or 9.70 volts.