For the BEC topology, a few studies reported average occupations based on X-ray powder diffraction (PXRD) measurements, which can be directly compared with our computational results presented above. In particular, Sastre et al. synthesized BEC samples that covered a broad range of Si/Ge ratios from ≈ 7 down to 1. Their data show a strong preference for D4R occupations at lower Ge loadings, up to approximately 3-4 Ge atoms per D4R unit (Si/Ge ≈ 3), which is replaced by a surge in occupation of adjacent and framework sites for high Ge contents, with the germanium occupation of adjacent and framework T sites becoming almost the same to that of the D4R site at Si/Ge = 1. Importantly, the authors also report that even at higher Si/Ge ratios, the germanium occupation of other than D4R sites is not completely negligible and accounts for a few tenths of per cent of the total Ge loading. These observations, also supported by an earlier report from the same group, are qualitatively in line with our simulations (see Figure and SI Figure ), with our predictions only mildly underestimating the D4R populations, which, e.g., leads to a break-even point between D4R and non-D4R T-site occupations to be observed slightly earlier (Si/Ge ≈ 1.9) then for the experiments (Si/Ge ≈ 1). The more recent PXRD data from Smeets et al. . for BEC with Si/Ge=5.1 localized, after a challenging diffraction pattern refinement, Ge atoms exclusively in D4R units -the discrepancy in the germanium occupation of D4R units between the work of Smeets et al. and the works discussed above may stem from the different OSDAs used for the BEC synthesis, since the role of OSDA in stabilization of different Ge distributions can be significant . Also, we note, that BEC zeolite has not been reported to give novel structural derivatives using the ADOR strategy, which is to be expected as BEC has a tetragonal symmetry (with crystallographically identical D4R units arranged along orthogonal directions). We confirm this by our calculations, observing the formation of 'layer-like' Ge-rich rods along both of these two directions (see Sections 3.2.2 and 3.3). Alternatively, the unsuccessful ADOR may be attributed to the very high content of D4R T sites (50 % of all T sites), hydrolysis of which would lead to extensive framework destruction, thereby preventing the rearrangement of the remaining components into a new zeolite framework.