Influence of In₂O₃ on Optical, EPR, and Structural Properties of Barium Borate Glasses Containing Cu²⁺ Spin Probe

To evaluate the effect of In₂O₃ on (30-x) BaO-69B₂O₃-xIn₂O₃-1CuO (x = 0.5, 1.0, 1.5, 2.0 and 2.5 mol%) glasses are described for their spectroscopic properties as well as physical and optical qualities. Bragg’s peak-free X-ray diffractograms confirmed the samples’ non-crystalline character. The increase of In₂O₃mole percent in the glasses has caused non-linear fluctuations in the physical parameters such as density and molar volume. Urbach energy measurements and optical band gaps have shown modest inflections with In₂O₃ composition. The ²B_1g → ²B_2g transition is responsible for the broad distinctive absorption band seen in optical absorption spectra caused by the Cu²⁺ spin probe. The spin-Hamiltonian parameters’ non-linear variation with indium oxide content suggests that the ligand field strength surrounding Cu²⁺ ions in glass samples has changed. Bonding parameter values are determined using EPR and optical absorption spectrum data, and it is discovered that they are ionic in nature. According to FTIR tests, when the amount of indium oxide in the glass grew, a small percentage of BO₃ units were converted into BO₄ units. Indium oxide in these glasses appears to generate notable modifications in the electrical conduction, transparency, and semiconducting behavior, according to the behavior of their optical, physical, and spectroscopic qualities.