The formation and properties of glass in the ZrF₄-BaF₂-ThF₄ system

The formation and properties of fluoride glasses in the ZrF₄-BaF₂-ThF₄ system were examined. The limits of the glassforming region were defined. A series of new quaternary glasses ZrF₄-BaF₂-ThF₄-MF_x (x = 1, 2, 3, and M = Li, Na, Ca, Sr, Zn, Cd, Pb, Al, Y, La, Gd) were obtained. The ultraviolet-visible and infrared transmission spectra, characteristic temperatures, refractive indices and densities for the fluoride glasses were determined. Glass in the quaternary systems was more stable than that in ternary system. These glasses were promising materials for infrared transmission, because of their good optical qualities and stability against devitrification.