We use a custom RDKit script to generate all combinations of carbon, silicon, and germanium in the bicyclo[2.2.2]octane class as illustrated in Scheme 2. With three variations in 8 atoms this yields a total of 3 8 possible combinations, which are reduced to 771 distinct molecules by symmetry. As described in detail in Supporting Information part I, we sample 9 conformations of each of the 771 molecules, which we optimize with GFN-xTB. The 6939 structures are further optimized using density functional theory (DFT) with the PBE functional and a DZP basis set as implemented in the Atomic simulation environment (ASE) and GPAW. This way we obtain molecular structures of good quality; although an assessment of relative energies and thermodynamic properties may require higher level calculations.