(3) Depict a plot with the sampling points projected onto the reactive coordinates. On the same figure, plot the potential contour along the reactive coordinates. To some extent, the comparison can indicate if the sampling covers the contour with a high cut-off energy. Figure shows the contour along the two reactive bonds, rOH (HO'H…O2) and rO'H (HO'…HO2), for the reaction OH + HO2 → H2O + O2. The sampled points with two reactive bond distances up to 5 Å are also shown in the same figure. Clearly, the points cover sufficient wide regions with denser points sampled in the valleys with relatively low energies from reactants to products. 91