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Quinary tellurite glass system in the percentages of 75TeO2–5Li2O–10ZnO–(10–x) Nb2O5–xEr2O3 where (x = 0.0, 0.5, 1.0, 1.5, 2.0, and 2.8 mol%) have been prepared and characterized. Both Fourier-transform-infrared (FTIR) and Raman spectroscopies were performed to study the structural changes correlated with the glass network. The thermal characteristics of the system were specified which showed a higher thermal stability (>100 °C) due to the formation of more bridging oxygen's (BO's) revealed by (FTIR) and Raman spectroscopies. The optical absorption spectra within near UV–visible regions were performed, and exhibited nine absorption bands centered around 1536, 977, 798, 653, 545, 524, 490, 450, and 443 nm corresponding to the 4I15/2 ground state to the various excited states 4I13/2, 4I11/2, 4I9/2, 4F9/2, 4S3/2, 2H11/2, 4F7/2,4F5/2, and 4F3/2 respectively. The same measurement also showed increasing values of the optical band gap (Eg) form 2.70 to 2.90 (eV) and decreasing the refractive index (n) from 2.48 to 2.42. Both the extinction coefficient data and the complex dielectric functions of the glasses were estimated. The different optical parameters were distinctly affected by increasing the Er2O3 (mol %) and the structural changes. The radiative properties of the glass were calculated using J-O parameters. The Branching ratio (β) of 4I13/2 → 4I15/2 transition peaked at 1520.48 nm for Er3+ ions has the highest value (1.000) also, the radiative lifetime (τ) of the same transition changed from 1.4510 to 1.8483. The gain cross-section of the laser transition level from 4G11/2 → 4I15/2 changed from 1.44 × 10−20 to 1.92 × 10−20 cm−1 in the existing glass system. The acquired results exhibited that the existent glass can be a good candidate in the fiber drawing and laser, non-linear optical applications.

As a continuation of the earlier work (synthesis and optical properties of new fluoro-tellurite glass within (TeO2 ZnO LiF Nb2O5 NaF) system), the thermal behavior and kinetics characterization of the oxyfluoride tellurite system have been achieved as a function of growing the mol% of NaF. The differential scanning calorimetry (DSC) technique at various heating rates under the non-isochronal conditions was used to identify the characteristic temperatures like the glass transition (Tg), the softening (Ts), the crystallization (Tc), the liquidus (TL), and the melting (Tm) of the system. The glass stability and glass forming ability (GFA) parameters were determined based on these characteristic temperatures. The activation energies of both the glass transition (Eg) and crystallization (Ec) have been computed by different methods. The Avrami kinetic constant (n) has been determined by more than a method to identify the crystallization succession.

New bismuth boro-tellurite glass within the compositions 20Bi 2 O 3 –25B 2 O 3 –(55–x) TeO 2 –x TiO 2 (0 ≤ x ≤ 10 mol%) have been prepared by normal melt quenching technique. The structure of the glass and then the glass-ceramic was investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and the transmission electron microscopy (TEM). The differential scanning calorimetry (DSC) measurements were carried out on the prepared glass samples to estimate their thermal behavior. Selected glass samples were heat treated at different annealing temperatures and times above the glass transition temperature. The optical absorption spectra were measured in the spectral range (380–600 nm) at room temperature. The Fourier transform infrared (FTIR) absorption spectra of all glasses were in the range (350–4000 cm − 1 ) have been recorded and designated.

New synthesis fluoro-tellurite in the form in [75TeO 2 –10ZnO–5LiF– (10 − γ ) Nb 2 O 5 – γ NaF] where γ = 0, 2, 4, 6, 8 and 10 mol% have been successfully synthesized by rapid melt-quenching technique. Also, the effect of doping the present prepared glasses by NaF on the optical properties has been discussed. Their densities were determined by Archimedes method. Values of the molar volume and the oxygen packing density were calculated. Both the Fourier-transform-infrared (FTIR) in the wavenumber range (350–4400 cm − 1 ) and the Raman spectroscopy in the range (40–4450 cm − 1 ) were used to prove the changes in the structure of the prepared glasses. The glass transition temperature (T g ), crystallization temperature (T c ) and melting temperature (T m ) were determined by using Differential Scanning Calorimetry (DSC) as a function of NaF (mol%) in the temperature range (298–923 K).Optical absorption spectra were recorded in the range (190–2500 nm). The indirect optical band gap (E opt ), Urbach energy (ΔE), refractive index (n), molar refraction (R m ), metallization criterion (M), electronic polarizability of the oxide ion (α o 2 ) and the optical basicity (Λ) of the prepared glasses were calculated.

Developing the microstructure and enhancing the optical parameters of TeO2 based glass with rare earth for many applications in various domains are considered as a revolution in materials science and technology. Hence, we prepared glass 75TeO2–10ZnO–5Li2O–(10-x) Nb2O5-xLa2O3 with x equal 0, 0.5, 1.0, 1.5, 2.0, 2.5 in mol% respectively by using melt-quench method. Differential Scanning Calorimetry (DSC) measurements proved that the glasses transition temperature (Tg) increased with La2O3 concentration. The mean average value of the activation energy (Ec) for crystallization varies from 272 to 361 kJ.mol−1 and 103 to 151 kJ.mol−1 for the first and second crystalline phases respectively. Synthesizing nanocrystallization La2Te3 with 15 nm diameter of the prepared glass was studied by using X-ray diffraction analysis (XRD), and scanning electron microscope (SEM) techniques. The values for energy gap (Eg) and refractive index (n) of the prepared glass were determined by using UV–spectroscopy. The structure of the present glass was studied by using the deconvolution of the FTIR spectra.