An initial comparison across surface intermediate binding energies can be made by comparing the energies between metals and metal surface planes. For the case of ammonia, the surface adsorption enthalpy of N*, NH*, NH 2 *, and NH 3 * have been calculated by Mavrikakis and coworkers on Re(0001) , Ru(0001) , Pt(111) , Pd(111) , and Au(111) . As shown in Figure and 3B, the adsorption enthalpies of the various intermediates are plotted relative to one another with the gamma values of the intermediates apparent in the fitted linear slopes. In the comparison of NH* and NH 2 *, the binding energy of NH* changes almost twice as much as the binding energy of NH 2 * (slope ~ γ NH2-NH ~ 0.53). Similarly, in the comparison of NH* and NH 3 *, the binding energy of NH* changes almost five times as much as the binding energy of NH 3 * (γ NH3-NH ~ 0.21). These comparisons exist across different metals, which is not a realistic scenario for implementing dynamic catalysis (i.e., metals cannot be periodically interchanged).