Moreover, discrete sites such as hollow, bridge, or atop cannot support the growth of expanding Cn oxygenates/hydrocarbons increasing size. Therefore, the reacting area in the model nanoparticle is expanded to the integrated active site shown in Figure . Below, we show that rapid surface diffusion of reaction intermediates can be assumed for Cu and, to a lesser extent, Pd. Hence, in our study reactive species are considered to move freely across facets, potentially attaching to edge atoms as needed. To build a tractable catalytic reaction network, we introduce an ansatz where highly reactive surface adsorbates preferentially interact with either low-reactivity species (CO, CO2, CH2O) or species at high surface concentrations, like H* under high H2 pressure, as illustrated in Figure . That is, we assume that low concentrations of highly reactive or unstable species make reactions between them improbable. The outcome of this preselection process for reaction steps is shown in Section S1 of the SI, while the full reaction graph detailing activation barriers and free energies is covered in the following subsection. The original multistep methodology to explore extensive catalytic reaction networks is described in Section S2.