Structural investigations of Mn2+ ions in alkali barium borophosphate glasses by EPR and optical absorption techniques

Results are reported for electron paramagnetic resonance (EPR) and optical absorption structural investigations of Mn2+ ions in alkali barium borophosphate glasses at room temperature. The Mn2+ EPR hyperfine sextet centered at g = 2 was observed in all the glasses for 1 mol% Mn2O3. The absorption spectra of Mn2+ ions in these glasses showed broad absorption bands characteristic of Mn2+ ions in octahedral symmetry. From the EPR and optical results, it is concluded that the site symmetry around Mn2+ ions is octahedral, and the nature of the bonding character is dominantly ionic. (C) 2000 Elsevier Science Ltd.