Magnon Spectrum of Alpha Oxygen

Abstract

The far-infrared absorption in solid alpha oxygen at 27 ${\mathrm{cm}}^{-1\mathrm{}}$ is shown to be definitively associated with the magnetic rather than orientational ordering in the crystal. A second magnetic excitation has been found at 6.5 ${\mathrm{cm}}^{-1\mathrm{}}$. The properties of both absorptions are described using the excitation-wave formalism.