Stabilization of heavy metals fluoride glasses

A new class of fluoride glasses has been isolated in the ternary system containing one transition metal fluoride ZnF2, one rare earth fluoride YbF3 and one actinide fluoride ThF4. The controlled addition of BaF2 playing the role of modifier allows the stabilization of glasses with low rate of crystallization in the quaternary system BaF2ThF4ZnF2YbF3. The infrared transmission can be extended to the 7–8 μ region, a significant improvement over the fluorozirconate glasses.