Effects of X-rays on Crystal Nucleation in Lithium Disilicate

The effects of exposure to a monochromatic 10 keV X-ray beam on thermally induced crystallization of lithium disilicate glass have been investigated and rendered two unexpected findings. First, it was found that an extended exposure during the nucleation heat treatment increased the number of nucleation sites. Second, it was observed that the effects extended far beyond the sample region that was directly exposed to the X-ray beam. The effects were confined to the direction perpendicular to the polarization of the synchrotron radiation beam that was used. The effects could be attributed to photo electrons created not only by the direct X-ray beam but also by the scattered radiation. Further evidence of the influence of photo electrons due to scattered X-rays is found in the results of an online crystallization study on a lysozyme solution