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.