EPR and optical absorption spectra of some paramagnetic ions in lithium fluoroborate glasses

Abstract The results of an electron paramagnetic resonance and optical absorption study of lithium fluoroborate glasses separately doped with Ti 3+ , Mn 2+ , Co 2+ , Ni 2+ , Cu 2+ and Gd 3+ ions are presented. The results are all consistent with optical absorption measurements and show that the ions are generally in sites with octahedral coordination except for Gd 3+ , which dictates its own environment and occupies sites surrounded by polyhedra of more or less irregularly distributed ligands with high coordination number (≥ 6).