Phonon spectra of barium halide nanocrystals in fluorozirconate glasses

Phonon spectra of BaCl2 and BaBr2 nanocrystals in fluorochloro- and fluorobromozirconate glasses were analyzed by Raman spectroscopy. The spectra coincide well with those from orthorhombic phase BaCl2 and BaBr2 bulk single crystals. Phonon frequencies for orthorhombic BaCl2 and BaBr2 were calculated from first-principles; a good agreement between the theoretical and the experimental data was achieved, showing a deviation of only 5 % at most in both cases.