Most perfect single crystals of three different com
positions with 2, 3, and 9% bismuth concentrations
were chosen for the Xray diffraction study. They were
imparted a spherical shape by rolling. A single crystal
of each of the three compositions with the best profiles
of diffraction peaks and the closest coincidence of the
intensities of symmetrically equivalent diffraction
reflections was chosen in a preliminary Xray diffrac
tion study.
C