stable glasses with variable applications. These glasses possess some of the highest densities, refractive indices and coefficients for second and third harmonic generations [1,2], Also, crystallized
Bi2O3 glasses containing rare-earth or transition metal ions have proven to be of special applications to laser host, tunable waveguide, tunable fiber grating [3,4]. Due to the high density and good
transparency of Bi2O3-glasses, they are useful for radiation-shielding and scintillation counters [5]. Extended studies on the constitution of bismuth borate glasses [6–10] and bismuth silicate glasses
[11–13] by infrared, and Raman spectroscopy, have indicated that Bi3+ ions can participate both as network modifier and as network former in the form of pyramidal BiO3 and/or octahedral BiO6 units
and the ratio of each unit depends on the composition of the glass.