Adsorption of carbonate species on silver. II. Electric ®eld e€ects

P. PAREDES OLIVERA; E. M. PATRITO

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 1998 vol. 44 p. 1247 - 1247

he adsorption of carbonate and bicarbonate ions on Ag(100) is investigated under high external electric fields, which simulate the environment of the electrochemical double layer. The e€ect of the electric ®eld was investigatedon several adsorbate properties such as binding energy, geometry, charge transfer and group vibrational frequencies.When positive electric ®elds are applied, the binding energy of the ions increases and the distance between the ions and the surface decreases. For carbonate, the bond length between the carbon atom and the coordinated oxygen atoms increases with the field while the C±O bond length involving the noncoordinated oxygen decreases. This weakening and strengthening of the bonds is reflected in the corresponding group vibrational frequencies. While thefrequency of the CO fragment perpendicular to the surface increases with the field, the frequency of the CO2 fragment decreases. The frequency of the CO group changes at a rate of 81.2 cm-1/V. In the c