Elucidation of state of combination of chlorine in pure quartz glass

Pure quartz glass contains various impurities, and among them, since chlorine is used as a raw material or dehydration treatment agent, it is apt to remain as an impurity. The number of its atoms can be confirmed by radioactivation analysis or EPMA, but the means to know the form of combination of the chlorine in ppm amount is not known at present. However this time, by irradiating the pure quartz glasses made by various methods with X-ray at 77K, and observing chlorine radical by ESR, thus guessing the precursor of this chlorine radical, the difference in the form of combination of chlorine was able to be classified, therefore, it is reported. The samples, X-ray irradiation and the results are described. It is considered that the state of combination of chlorine was affected by the manufacturing method. For those by Ar plasma process, the form of collected Si-Cl, for those by Ar+O2 plasma process, the form of Cl2 molecules, and for those by soot process, the form of dispersed Si-Cl were proposed. Moreover, by irradiating the samples of excessive oxygen type with X-ray at low temperature, the new signal beta having four sharp peaks was observed. (K.I.)