Hence, if the free energy difference between adsorption and desorption, denoted as ∆G * , is greater than zero with ∆G * > 0, the reactants bind too weakly to the catalyst. Conversely, if ∆G * < 0, the molecules are strongly bound, leading to poor desorption behavior. The ideal situation, with ∆G * = 0, corresponds to the original Sabatier principle and results in optimal catalytic activity and reaction yields . These assumptions also relate to volcano plots, which show the relationship between different interaction energies and catalytic activity, with the most favorable and ideal catalyst located at the peak of the volcano plot .