Raman and EPR studies of β-irradiated oxide glasses: The effect of iron concentration

The study of iron concentration effect on the oxide glass structure has shown evidence of depolymerization of the vitreous network with increasing iron content and especially with Fe2+ amount for all types of glass. For all glass compositions studied, we observe by EPR a blockage of defects creation processes under β irradiation for glasses doped with more than 1 wt% of Fe2O3. Reduction processes of Fe3+ under irradiation is also detected. Moreover for sodalime glass samples, β irradiation induces depolymerization, in opposite of what was expected and observed for other glasses. Anyway, adding iron up to 4 wt% Fe2O3 always diminishes the β irradiation effects. This has been linked to the observed iron reduction and to the ability of iron, maybe coupled with charge trapping processes to consume excitons.