Next, the Figures show the progress in expansion from 0 th to 3 rd order in ΔICOHP. The expansion improves linearity for all groups, but 4d and 5d systems become parallel with very similar slopes (~0.82). However, 3d group, which features magnetic systems, exhibits a comparatively smaller slope (~0.36). In all cases the 3rd order ΔICOHP still provides a good linear fit. The 3 rd order and full expansions are nearly identical with little extra improvement (see SI S12). Clearly, a linear one to one description of adsorption across oxides can be established considering expanded ΔICOHP for a given group. This result is distinct from our bulk COHP studies where a cubic (non-linear) dependence was found previously 1,2 suggesting error cancelation.