Spectroscopic and Optical Studies of Molybdenum Ions in CdO-SrO-B2O3-SiO2 (CdSBSi) Glass System

In this work, the electron paramagnetic resonance (EPR) and optical absorption investigations at room temperature have been conducted on MoO3-CdO-SrO-B2O3-SiO2 glasses by altering percentages of SrO and MoO3. The distinctive EPR spectra of Mo5+ appeared at centered around g ~ 2.00 and are attributed to the Mo5+ ion within an axially distorted octahedral coordination sphere. Red shift was observed near an absorption edge in the UV spectra. The fundamental UV edges of absorption of the glasses were used to evaluate the Urbach energies and optical band gaps for transitions which occur directly or indirectly. A theoretical evaluation of glasses’ optical basicity (Λth) has been conducted. The interaction between oxygen ligands and Mo5+ ions has been demonstrated to be improved. The covalent-to-ionic ratios of the glass can be classified using optical basicity, since a higher optical basicity indicates a lower degree of covalence.