Thermodynamic and ab initio calculations of chemisorption energies of ions.

HARRELL SELLERS; E. M. PATRITO; P. PAREDES OLIVERA

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 1996 vol. 356 p. 222 - 222

e have performed thermodynamic calculations of the heats of adsorption of H and H ÷ and quantum mechanical (relativisticeffective core potential (RECP) Hartree-Fock+electron correlation) calculations of the zero coverage limit binding energies ofhydrogen cation and anion on cluster models of the Ag(lll) surface of varying size in order to determine the demands placed onthe theory by the ionic adsorbates. The thermodynamic discussion has implications for the results of the quantum mechanical calculations. The binding energies derived from thermodynamic data are employed as reference values for comparison purposes. In general we find that larger clusters are required for ionic adsorbates than neutral adsorbates. Our larger cluster SCF calculationsgive binding energies in the ranges of 245-249 and 124 130 kcal/mol for H ÷ and H-, respectively, which agree well with the thermodynamic values of 255 and 142 kcal/mol. The MP2 correlation contributions to the binding energies were small and s