Fresnoite crystal structure in glass-ceramics

A glass-ceramic including a crystallite of fresnoite crystal phase was prepared by crystallization of glass with a composition of 2BaOTiO23SiO2. The length of the a-axis of fresnoite in the glass-ceramic was shorter than that of the single crystal, and that of the c-axis was longer. Parameters of the crystal structure were refined using the Rietveld method, and the refinement was terminated to a profile reliability factor of 0.080. It was concluded that atomic displacements of the single crystal depended on the crystallization-induced stress formed in the crystallization process and the thermal contraction stress created in the cooling process after crystallization, and that these stresses were responsible for the expansion and contraction of the crystal lattice.