Specific features of photoluminescence of oxygen-deficient centers in irradiated silica glass

A set of spectroscopy methods was used to study radiative and nonradiative processes at oxygen-deficient centers (ODCs) in glassy SiO2 exposed to fast electrons. Quantitative characteristics of electron transitions at ODCs were determined. It was shown that the excited singlet S1 state of ODCs could be ionized. The transfer of excitation energy from nonbridging oxygen centers to ODCs, which was followed by filling of the triplet state of the latter, was revealed. Regular features of relaxation processes and luminescence properties of ODCs were consistently interpreted in terms of the “neutral oxygen vacancy” model.