Fig. 2

Predicted VSR slopes for AH X species. Values are predicted based on Eq. (12). Labels indicate adsorbate A/B for CH X (blue), NH X (green), and OH X (red). The black line indicates parity. The fitted slopes to DFT data are from the data in Fig. 1 and fit according to Eq. (13). Included are the perpendicular frequencies of the adsorbates on the atop sites of the (100) (circles), (110) (triangles), and (111) (squares) facets