Infrared photoluminescence of preexisting or irradiation-induced interstitial oxygen molecules in glassySiO2and α-quartz
A sensitive technique for detecting interstitial ${\mathrm{O}}_{2}$ molecules in ${\mathrm{SiO}}_{2}$ is demonstrated by measuring their infrared $\stackrel{\ensuremath{\rightarrow}}{a}X$ luminescence at 1272.2 nm under a Ti-sapphire laser excitation into the ${\mathrm{O}}_{2}\stackrel{\ensuremath{\rightarrow}}{X}b$ absorption band at 765 nm. Contrary to the case of ${\mathrm{O}}_{2}$ trapped in inert gas matrices, the visible emission of ${\mathrm{O}}_{2}$ corresponding to the direct $\stackrel{\ensuremath{\rightarrow}}{b}X$ transition is not found. Examination of different neutron- and gamma-irradiated glassy ${\mathrm{SiO}}_{2}$ and \ensuremath{\alpha}-quartz samples reveals radiation-in…