Physical and spectroscopic studies on manganese ions in lead halo borate glasses
Abstract
Lead halo borate glass systems containing manganese ions have been investigated to study the role of halide ions on the physical, optical and EPR studies. The amorphous phase of the prepared glass samples xPbX2–(30−x)PbO–69.5B2O3–0.5MnO2 with X = F, Cl and Br and 5≤x≤25 mol% was confirmed from their X-ray diffraction spectra. Ionic radii of the halides played an important role in the physical properties. From the optical absorption spectra, optical band gap and Urbach energy values were evaluated. The EPR spectra have shown a six-line hyperfine (HF) structure centered at g≈2.0 and attributed to Mn2+ centers in octahedral symmetry. The other signals at g≈3.3 and 4.3 were attributed to the rhombic surroundings of Mn2+ ions. The negative shift in g-value revealed highly ionic environment around the Mn2+ ion in the glass hosts. The HF splitting constant (A), number of spins (N) and susceptibility (χ) values of the prepared glasses were also reported.
