The first-order Raman spectrum of mixed crystals of ${\mathrm{Ca}}_x{\mathrm{Sr}}_{1-x}{\mathrm{F}}_2$ and ${\mathrm{Sr}}_x{\mathrm{Ba}}_{1-x}{\mathrm{F}}_2$ has been measured. The Raman frequency varies linearly with concentration, while the Raman linewidth exhibits a maximum near the 50% mixture.

• Received 25 August 1966

DOI:https://doi.org/10.1103/PhysRevLett.17.755