Electron-density maps for Sb89Te11 at room temperature based on Fo; only positive contours are drawn at intervals of 500 e A−3. These maps, (a), (b) and (c), correspond to the results obtained from three kinds of the Rietveld analyses, (a), (b) and (c), shown in Table 3. The crystal obtained a stagnant atomic arrangement after high-temperature measurements. These maps are almost identical to Fourier maps based on Fc. The modulations in the displacement of the two atoms in this binary alloy are indicated by the cross-lying curves for Sb in black and for Te in gray. These were analyzed by using different functions to describe the atomic displacement; however, we can see that they are almost the same.