Fig. 1.
Scaling of the ν ⊥ modes for AHX adsorbates with their atomic counterparts from DFT. Species are a CHX, b NHX, and c OHX. Adsorption is on the atop site of (100) transition metal surfaces. For a and b, respectively: green triangles = CH and NH, blue circles = CH2 and NH2, and red squares = CH3. For OHX species c, ν ⊥ frequencies on the (110) and (111) facets are also included and green triangles = (100), blue circles = (111) and red squares = (100). The slopes of the regressed lines in a are 0.14, 0.42, and 0.86 for the red, blue, and green lines, respectively. In b, the slopes of the regressed lines are 0.26 and 0.64 for the blue and green lines, respectively. In c the slopes of the regressed lines are 0.43, 0.42, and 0.48 for the red, blue and green lines, respectively. All intercepts are positive