To prove that this good performance is not fortuitous, we use a 5-fold cross-validation procedure on the whole dataset and found an average RMSE of 0.37 kJ mol -1 with a standard Figure : Scatter plot of the exchange free energy predicted by the model. There is a good agreement between the predicted and true values. On the test set, there is an RMSE of 0.37 kJ mol -1 and an MAE of 0.21 kJ mol -1 . This plot is equivalent to the scatter plot between the logarithm of the ambient-pressure selectivity values (see Figure ). The corresponding errors for the ambient-selectivity are 2.5 and 1.1 for respectively the RMSE and MAE of the selectivity, and 0.065 and 0.038 for the RMSE and MAE of its log 10 . deviation of 0.01 kJ mol -1 , which is consistent with the performance given by the train/test split performed.