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The electronic structure, adsorption and bonding of two isomer molecules, orthocarborane and metacarborane are compared. Significant differences in the experimental binding energies are noticed

A study was conducted relating to research on the nature and occurrence of copper surface oxidation in aqueous solution-related ambient environments. Surface enhanced Raman spectroscopy was used to probe the surface structural changes linked to potential dependent oxidation and reduction of copper in alkaline, neutral and acidic media. Experimental methodology, findings and implications are discussed. Results are also compared with evidence derived from previous experiments which confirm adsorbed oxygen on copper electrodes.

Synchrotron-based high-resolution photoemission was used to analyze adsorption and dissociation of H2S and S2 on a series of oxide and metal/oxide surfaces. H2S and S2 generally interact with the metal centers of oxides. At 300 K, H2S undergoes total decomposition. The rate of decomposition on Al2O3 is much lower than those observed on Cr3O4, Cr2O3, ZnO and Cu2O. For these systems, the smaller the band gap in the oxide, the bigger its reactivity toward S-containing molecules. The use of ab initio self-consistent-field calculations and a model that unifies perturbation theory with Huckel and tight-binding approach are discussed.

The metal/electrolyte interface is analyzed by employing jellium model for metal surfaces and Bethe approximation for dipolar interactions. The total surface energy considering the metal-solvent interactions is then calculated using a one-parameter family of trial functions for the electronic density profile. A systematic analysis of the metal-solvent bond length and its dependence on electrode charge density is presented. The results are discussed.

A study was conducted to assess the validity of a simple sharp-kink approximation which relates the contact angle of a liquid on a surface to its density, its surface tension, and the effective molecule-surface potential. The equation might be applied to study the temperature-dependence of the contact angle for helium or alkali metal surfaces.

A systematic density functional theory (DFT) of hydrogen adsorption on Fe(111) at various coverages is presented. The coverage effects on the adsorption configrations and adsorption energies are addressed.

A study carried out has developed a new electronic composition-property relationship between the adsorption energy of molecules binding unequally to multiple atoms on metal surfaces and the electronic properties of the surface. Details of the consequences of our electronic composition-property relationship for catalyst design are discussed.

The adsorption of CO on the Pt{100}, Pt{110} and Pt{111} surfaces was investigated sing cluster model representations of the different surfaces and ab initio calculations. Results showed that the calculated equilibrium structures and vibrational spectra are independent of the cluster model, but the computed interaction energies are very sensitive to it. An analysis of the chemisorption bond using the constrained space orbital variation method revealed that the initial Pauli repulsion is the main contributing factor to the difference in the vibrational frequency of chemisorbed CO.