This discrepancy between experimental and simulational results for the CO 2 RR has also been noted by Bohra et al. In likely the most egregious example, we know experimentally that Ag and Au produce CO. However, Density Functional Theory (DFT) calculations predicts that the formation of HCOOH has a lower barrier compared to CO, meaning that these elements preferentially produce HCOOH, in disagreement with experimental knowledge. As DFT is generally very good at qualitatively predicting (electro)catalytic trends in agreement with experiments, 2 there must be some factor that has not yet been accounted for in atomic-scale simulations.