The search was performed for a reaction time of 3,600 s at reaction temperatures of 500, 750, and 1,000 K. The SC-AFIR search identified 21,661 local minima (LMs) and 26,212 paths connecting the LMs for the Pd(111) case and 13,227 LMs and 15,880 paths for the Pd(100) case. In both cases, the complete oxidation product CO2 + 2H2O was observed. Figure and show the energy profiles of the most feasible paths to the complete oxidation product on the (111) and (100) surfaces, respectively. On the (111) surface, CO2 + 2H2O is the most stable kinetically accessible species. In contrast, the CO2 + H + OH + H2O species exhibits the lowest energy on the (100) surface. This is because the (100) surface, which is less stable than the (111) surface, is stabilized by the chemisorption of OH and H. Table lists the five most populated (kinetically abundant) species after 3,600 s of reaction at 750 K, starting from the initial structure shown in Fig. . The most populated species on the (111) and (100) surfaces are CO + O + 2H2O and CO + 2OH + H2O, respectively. The higher population of these states, which have higher Gibbs energies (Fig. ), is due to the configurational entropy resulting from the larger number of chemisorption patterns in these states. Actually, in CO + O + 2H2O on the (111) surface, there are 208 corresponding LMs and among these 121 LMs have population > 0.1% accounting for 36.3%, indicating that many LMs with different chemisorption patterns contribute to the total population 39.1% in Table . On the other hand, in CO2 + 2H2O on the (111) surface, there are 42 corresponding LMs and among these only 10 LMs have population > 0.1% accounting for 33.4%. Similarly, in CO + 2OH + H2O on the (100) surface, there are 158 corresponding LMs and among these 85 LMs have population > 0.1% accounting for 54.4%. In CO2 + OH + H + H2O on the (100) surface, there are 199 corresponding LMs and among these only 31