Structural and thermal properties of some zinc borate glasses containing gadolinium ions

Glasses in the system (Gd₂O₃)_x·(B₂O₃)_(60−x)·(ZnO)₄₀ (0 ≤ × ≤ 15 mol%) have been prepared by the melt-quenching technique. The local structure and the thermal behaviour of the obtained glasses were investigated using X-ray diffraction (XRD), differential thermal analysis (DTA) and Fourier transform infrared (FTIR) spectroscopy. The XRD pattern of the glasses confirmed their amorphous nature. Compositional dependence of the glass transition (T_g), fragility index (F), activation energy of the glass transition (E_g), activation energy for the crystallization process (E_p) were determined by DTA investigations. FTIR data revealed that the short-range order of glasses is affected by the addition of the Gd₂O₃ to the host glass matrix. The compositional dependence of the different structural units which appear in the investigated glasses was followed. FTIR data suggest that the gadolinium ions play the network modifier role in the studied glasses.