(a) Evolution of the laboratory X-ray powder diffraction patterns of $\mathrm{Ca}_{2} \mathrm{MSbO}_{6}(\mathrm{M}=\mathrm{Nd}, \mathrm{Eu}$, Gd, Dy, Ho, Er, Tm, Yb and Y) at RT. (b) Details from the X-ray powder diffraction patterns of the latter compounds in the selected $2 \theta$ intervals; $18^{\circ}-26^{\circ}, 29^{\circ}-33^{\circ}$ and $54^{\circ}-57^{\circ}$, to show the continuous evolution of the patterns with the ionic radius of the $\mathrm{M}^{3+}$ cation.
(a) Evolution of the laboratory X-ray powder diffraction patterns of \mathrm{Ca}_{2} \mathrm{MSbO}_{6}(\mathrm{M}=\mathrm{Nd}, \mathrm{Eu}, Gd, Dy, Ho, Er, Tm, Yb and Y) at RT. (b) Details from the X-ray powder diffraction patterns of the latter compounds in the selected 2 \theta intervals; 18^{\circ}-26^{\circ}, 29^{\circ}-33^{\circ} and 54^{\circ}-57^{\circ}, to show the continuous evolution of the patterns with the ionic radius of the \mathrm{M}^{3+} cation.