Abstract
The optical phonons of BeO crystals have been studied by measurements of polarized infrared reflection spectra in the range 400-4000 . Raman spectra for shifts in the range 100-1500 at room temperature were analyzed. Oscillator fits to the reflectivity spectra lead to values for the frequency, linewidth, and strength of the and vibrations. The infrared data are confirmed by the Raman measurements, which also give the Raman-active-only vibrations. Within experimental error, the high-frequency mode at 684 coincides with the transverse mode and is at about twice the frequency of the low-frequency mode. The multiple-phonon absorptions at zone boundaries have also been measured at room temperature on the high-energy side of the reststrahlen band up to 4000 .
- Received 5 October 1967
DOI:https://doi.org/10.1103/PhysRev.166.673
©1968 American Physical Society