Figure 2. Changes in the crystal structure and the thermal expansion behavior in the solid solution series Ba_1-xSr_xZn₂Si₂O₇ for different values of x.

On the left side, X-ray powder diffraction patterns measured at room temperature are presented. In the lower part of the graph, the peak positions, determined by Klasens et al. in 1957¹¹ (A), those calculated from the crystal structure of a Ba_0.6Sr₀.₄Zn₂Si₂O₇ single crystal (B) and those of LT-BaZn₂Si₂O₇ taken from ref. 13 (C) are given. In the upper part, measured diffractograms with x = 0, 0.1 and 0.9 are shown. On the right side, the thermal expansion behavior, determined via dilatometry, is given for x = 0, 0.1 and 0.8. The curve of the sample with x = 0 was taken from Ref. 10.