) measured at T oven = 150 • C at different t OS , shown in Fig. and, indicates full conversion of acetylene and is consistent with the analysis of the SG rules in Fig. , which indicates that the activity for these systems only drops at very low amounts of palladium. The measured and predicted ethylene selectivity (S measured C2H4 and S SISSO C2H4 , respectively) are shown in Fig. and as blue and red squares. Note that the predictions are slightly different from the predictions shown in Fig. In addition to the bimetallic systems, we also used the AI models to predict the reactivity of the Pd-Ag-Cu system as an example of a trimetallic material. This system is represented as an orange triangle in Fig. . The SG constraints indicate that high X C2H2 can be achieved for most of the compositions, with the exception of silver-and copper-rich systems. The predicted S SISSO C2H4 values (Fig. and) indicate that the selectivity increases with t OS , in particular for silver-and copper-rich compositions. The composition for which the selectivity presents its maximum value at t OS = 400 min is approximately Pd 1 Ag 5 Cu 1 . The trimetallic Pd 1 Ag 5 Cu 1 system was experimentally synthesized, characterized by TEM and EDX-SEM and tested. The measured D µ and w metal for Pd 1 Ag 5 Cu 1 is equal to 6.03 nm and 0.0145, respectively. It presents an initial measured selectivity of 62 % at 27 min, which slightly increases to 65% at 405 min (Fig. ). Thus, the trimetallic Pd 1 Ag 5 Cu 1 material is as selective as the most selective material of the training set (Pd 1 Ag 9 ). Even though the predicted selectivity values deviate significantly from the measurements at the beginning of the reaction, the SISSO model correctly predicts the ethylene selectivity of Pd 1 Ag 5 Cu 1 at long t OS , e.g., t OS > 300 min. Besides, the model is qualitatively correct in that the selectivity increases with t OS . These results indicate the potential of the AI approach to guide the design of materials.