Diffusion of H2O on a NaCl(100)

Abstract

The motion of D2O monomers is investigated on a NaCl(100) bilayer on Ag(111) between 42.3 and 52.3 K by scanning tunneling microscopy and density functional theory. In previous work, we did investigate the diffusion mechanism of H2O on NaCl(100) at low coverage. For that we determined the energy barriers associated with different hopping mechanisms, classified as translations and reorientations of the water molecule. The combination of these hopping mechanisms leads to net movement of the molecule along the surface with relatively low energetic cost, compared with bare parallel translation of the water molecule. In the recent work the mechanism of the motion is identified by comparison of the experimental results to theoretical calculations. Via low temperature adsorption site determination in connection with density functional theory, we reveal an influence of the metallic support onto the intermediate state of the diffusive motion.