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water hexagonal structure becomes even more irregular. 

Though the average surface height doesn’t change very much, see ΔAg in Table I, the individual silver atoms on the surface do move quite a bit more. This can be seen clearly in the side view of Fig. 1b. Another ob- servation is that the water molecules that do not lose their hydrogens are not oriented parallel to the surface, they are tilted with an angle of 7.69 $^{◦}$. We report a neg- ative adsorption energy of -0.1876eV, as predicted by DMol $^{3}$, indicating the stable structure. This is contrary to what was reported in Refs. 22 and 23. Previously, we carefully compared equilibrium geometries predicted by CASTEP and DMol 3 with different molecules 20,24 and showed that the use of localized basis in DMol 3 

is beneficial in terms of prediction of stable geometries. Consequently equilibrium molecule-surface distances pre- dicted by LDA DMol 3 method better agree with those generated by VASP package including van der Waals contributions 25 and agree much better with experiment. 

Methanol (CH$_{3}$OH, Fig. 1d) and ethanol (CH$_{3}$CH$_{3}$OH, Fig. 1f) adsorb very similarly on the surface of silver (see Table I). Once the O-H bond is broken, the molecules rotate to bring the oxygen closer to the surface, however, the molecules also shift on the surface and position themselves such that the oxygen is between three Ag surface atoms. It is important to note that although a stable configuration was found with the O-H bond broken for both methanol and ethanol, those 

