Electron paramagnetic resonance studies on mixed alkaline earth oxide borotellurite glasses doped with Cu2+ and VO2+ transition metal ions

Mixed alkaline earth boro-tellurite glasses were used to create and examine the effects of doping transition metal ions (namely CuO and V2O5) via the application of Electron Paramagnetic Resonance (EPR) spectroscopy. The spectra seen in copper-doped glasses exhibit three parallel lines, with a fourth line merging with the perpendicular lines. These lines correspond to the typical resonance signals. The evaluation and detailed explanation of several spin-Hamiltonian and bonding factors were conducted. The findings indicate that the Cu2+ ions occupy tetragonally deformed octahedral locations, with the ground state being 2B1g. In the context of vanadium-doped glasses, it was possible to distinguish eight distinct hyperfine lines. Analysis of the spectra revealed that the value of g‖ is less than both g⊥ and ge, indicating a tetragonally compressed complex for the V4+ ions. Additionally, it was discovered that the value of A‖ is greater than A⊥, further supporting the conclusion of a tetragonally compressed complex.