18O-labeled interstitial oxygen molecules as probes to study reactions involving oxygen-related species in amorphous SiO2

Abstract Isotope labeling has been widely used to study reactions involving oxygen species in amorphous SiO 2 ( a -SiO 2 ). This article briefly describes recent progress in 18 O labeling techniques to study reactions involving interstitial oxygen molecules (O 2 ), which is one of the most important excess oxygen species in a -SiO 2 . The primary focus will be on the combination of the 18 O labeling with photoluminescence spectroscopy, which enables sensitive and selective detection of interstitial O 2 . Advantages of this method and results of evaluation of oxygen exchange between interstitial O 2 and the Si―O network of a -SiO 2 will be presented.