Determination of Sapphire Stoichiometry by X-RAY Scattering

1Safronov, RI
1SSС «Institute for Single Crystals», NAS of Ukraine, Kharkiv
Nauka innov. 2011, 7(3):36-38
https://doi.org/10.15407/scin7.03.036
Section: Scientific and Technical Innovative Projects of National Academy of Sciences of Ukraine
Language: Ukrainian
Abstract: 
The possibility of sapphire stoichiometry determination by X-ray dispersion measurements was studied. The measurements were carried out using the X-ray fluorescent spectrometer adjusted in X-ray optical scheme with the secondary radiation source. The parameters measured were X-ray dispersion integral intensities of coherent (Ik) and incoherent (Ir) peaks. The concentrations of the F- and F + centers were measured by the optical absorption at 206, 225 and 255 nm wavelengths. The existence of a certain relation between Ik/Ir value and sapphire stoichiometry was revealed. The formula for cation vacancies quantity determination in the sapphire is proposed.
Keywords: non-destructive testing methods, stoichiometry of crystal composition, X-ray fluorescent spectrometer, X-ray scattering
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