Preparation of glasses in the Ge–Sb–Se–I system via volatile iodides

• A new method for preparation of Ge–Sb–Se–I glasses has been developed.
• Thermodynamic modeling of heterogeneous equilibrium in GeI4–Se system was performed.
• The produced Ge–Sb–Se–I glasses are characterized by low content of impurities.

Glass samples of the Ge–Sb–Se–I system were prepared by reacting germanium tetraiodide and antimony triiodide with selenium in a set-up which provides selective removal of iodine from the melt. Thermodynamic modeling of purification reactions of the components is shown. The glasses are analyzed by X-ray spectral microanalysis, differential scanning calorimetry, IR spectroscopy, Raman scattering spectroscopy, and laser mass spectrometry. In the purest examples of these glasses, the content of residual impurities is: hydrogen—0.1 ppm mol, silicon—0.02 ppm wt., and transition metals—less than 0.5 ppm wt.