Synthesis and Study of Spectral-Luminescent Properties of Oxyfluoride Glasses of System BaF₂–BaO–SiO₂–B₂O₃–Bi₂O₃–ZnO–Y₂O₃ Activated by Oxides Er₂O₃ and Yb₂O₃

Oxyfluoride glasses in the BaF₂–BaO–SiO₂–B₂O₃–Bi₂O₃–ZnO–Y₂O₃ system were developed and synthesized with various ratios of the initial components. The spectral-luminescent properties of glasses activated with oxides Er₂O₃ and Yb₂O₃ were investigated. According to X-ray powder diffraction, all glass samples are X-ray amorphous, and the glass transition temperature (T_g) was determined. The study of the local structure using IR spectroscopy revealed that the glasses, regardless of composition, contain complex polyborate anions formed by the [BO₃] and [BO₄] groups. It was also shown that bismuth integrates into the glass network, forming Bi–O–Si bonds and network formers in the form of the [BiO₆] groups.