Abstract
The unit-cell parameter of SrTiO3 samples of different structural quality, grown by the Verneuil method, was studied. Measurements on the interplanar spacings of SrTiO3 in the clear and in the blue regions were made on homogeneous powders (20-30 micron) with a DRON-2.0 X-ray diffractometer, using CuKalpha radiation, separated with a LiF monochromator. A comparative technique used to determine the spacings enabled successive measurements of the diffracted X-rays from two or several samples at the same goniometer angle, eliminating goniometer error and giving clear indications of any differences between comparable samples. Data obtained were averaged and tabulated. Error in the determination of the unit-cell parameter was plus or minus 0.1% (relative) and plus or minus 0.003% (absolute). Linear extrapolation was performed and differences in the lattice constants of the two types evaluated. The change in unit-cell parameter value in the coloured portion compared to the clear region was 0.0001 nm, a difference apparently due to lattice compression resulting from anion vacancies in the 'blue spot'. 5 refs.