| Abstract
| - The adsorption of formic acid and sodium formate on the stoichiometric anatase (101) surface has beenstudied by means of density functional calculations with a slab geometry. On the clean surface, the moststable adsorption structure for HCOOH is a molecular monodentate configuration, hydrogen bonded to asurface bridging oxygen, while for HCOONa a dissociated bridging bidentate geometry is preferred. Thebidentate chelating structure is energetically unstable for both the acid and the salt. On the hydrated surface,both HCOOH and HCOONa preferentially form an inner-sphere adsorption complex. HCOOH maintains amonodentate coordination, but, due to the interaction with a nearby water molecule, it becomes dissociated,while HCOONa again prefers a bridging bidentate structure. The energies for adsorption from an aqueoussolution are estimated to be 0.30 and 0.79 eV for HCOOH and HCOONa, respectively.
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