Ionizing Potentials and Far Ultra-Violet Lines of Light Atoms

By an interpolation the ionizing potentials of F and ${\mathrm{F}}^{+}$ are found to be 17.4 and 34.5 volts. These new values improve the regularity of the relationships of the values of ${\left(\frac{\nu }{R}\right)}^{\frac{1}{2}}$ corresponding to the ionizing potentials of the atoms of the first short period. The energy necessary for the removal of a $2s$ electron from each of many of the atoms and ions of these elements ($L_{11}$ levels for an atom) is calculated by use of the $s^2{p}^{n-1\mathrm{}}-s{p}^n$ lines.