Powder XRD patterns simulated for different APB types (black lines). The patterns, which are labeled (a), (b), (c), (e) and (f), were simulated using the corresponding models from Fig. 3. The symbols c and nc denote conservative and non-conservative APBs, respectively. Measured XRD patterns are plotted in gray. For the sake of simplicity, the diffraction lines are labeled with cubic indices. For tetragonal indices, the reader is referred to Table 2.