We observe that all the metals are nicely grouped according to their main product color. Note especially the separation between the CO-(blue) and HCOOH-producing (yellow) metals, which previous descriptor plots were unable to fully separate. All 4 PCA plots describe 70+% of the variation in the dataset (additional PCA plots and discussion can be found in the SI section "Additional PCA Results".). This is a strong indicator that a 2D and 3D representation of metal catalyst product distribution is suitable. Note that simply using a 2D descriptor plot with PC#1 vs.