Finally, Figure shows the effect that different ϵ a have on the row-dependent scaling behaviour. By plotting E ortho against E ortho at ϵ a = -5 eV (for O*), we determine for which range of ϵ a row dependent scaling is to be expected. For ϵ a = -3 eV, E ortho for 3d, 4d and 5d elements show less mismatch than for the case of ϵ a = -1 eV. Overall, adsorbates with similar ϵ a values are likely to not show row-dependence in their scaling behaviour. The range of allowable ϵ a values depends on the variation of E ortho across and along rows of the periodic table.