While linear scaling is undoubtedly valid for many adsorbates and metals (see data for Rh(111) in Supporting Information Table ), most models that implement the use of linear scaling are for low adsorbate coverage conditions. These relationships are based on the dband model, which can predict well for pure metals, but are only valid for a small subset of alloy materials. With these caveats, the models generated automatically by RMG should be regarded not as a final product, but as a useful starting point for further analysis. A good next step would be performing high level theory DFT calculations on metals in the region identified in the simulations giving highest synthesis gas yield.