Optical Measurements on Magnetite

The optical transmission of powdered single crystals of magnetite was measured in the spectral range from 200 to 4000 ${\mathrm{cm}}^{-1\mathrm{}}$ at temperatures between 77 and 300 K. The measurements are compared with those on Ti-substituted magnetite. The spectrum of pure magnetite shows drastic changes at the Verwey transition. In the low-temperature phase, a small splitting up of the two high-temperature phonon bands is observed.