Potassium Superoxide and the Three-Electron Bond

The highest oxide of potassium is shown to be paramagnetic, with a susceptibility corresponding to the formula KO₂, the crystals being supposed to contain O₂ ions in a ²II state. The electronic structure $:\mathrm{O}{\displaystyle {lim}_{\mathrm{..}}}\mathrm{:⃛}\mathrm{O}{\displaystyle {lim}_{\mathrm{..}}}{:}^{-}$ is proposed for the superoxide ion. It is suggested that the substance be called potassium superoxide rather than tetroxide.