Showing papers by "Jens K. Nørskov published in 1979"
TL;DR: In this paper, a conceptual model for the photon emission observed during chemisorption on metals was developed and extended to electron emission, with estimated molecular velocities and electronic structure in the region slightly outside the surface, the probability of an electronically excited intermediate state is calculated.
137 citations
TL;DR: In this article, the authors present a theoretical description of the interaction between molecules and metal surfaces and the reactivity of chemisorbed molecules, and the qualitative concepts and considerations are based on results of self-consistent calculations on simple models that stress the extended nature of the conduction-electron states.
134 citations
TL;DR: Using molecular orbital correlation diagrams, it was shown that the chemiluminescence observed during halogen chemisorption on sodium can be ascribed to the filling of the initially empty antibonding halogen MO by a radiative process as discussed by the authors.
127 citations
TL;DR: In this article, an electronic mechanism for energy dissipation was proposed to account for the loss in adsorbate kinetic energy necessary for the trapping of an adorbate in the surface potential well.
104 citations
TL;DR: In this paper, a spin-polarized self-consistent field calculation of the impurity excitation energies was presented for a single interstitial hydrogen and a single substitutional hydrogen.
Abstract: Recent progress in the theoretical description of hydrogen impurities in metals, as described by the jellium model, and their interaction mutually and with vacancies are described. In addition to giving a detailed account of the author's contribution, the paper presents new results for the spectra of the hydrogen-induced states. These show for single interstitial hydrogen a doubly occupied bound state, while substitutional hydrogen has an atomic resonance in the conduction band. In both cases the state is situated just below the "local bottom of the band," as defined by the clean-metal effective potential at the impurity site. When two such states interact, both the bonding and the antibonding molecular orbitals get filled except at the lowest metallic densities, and a repulsive hydrogen-hydrogen interaction results. Spin-polarized $\ensuremath{\Delta}$ self-consistent-field calculations of the impurity excitation energies are presented. The results compare well with the one-electron binding energies of the bound states and with the excitation energies calculated by Vinter. The hydrogen impurity spectra presented can therefore be expected to represent approximately experimental excitation spectra of interstitial and substitutional hydrogen in free-electron-like metals.
97 citations
TL;DR: In this article, a model with H2 standing upright on a jellium surface was used to study the reactivity of metals and their ability to break chemical bonds, and data for the adsorbate-induced electron structure and potential energy curves with substrate parameters characteristic for Al, Mg and Na were presented.
Abstract: As a first step towards an understanding of the reactivity of metals and their ability to break chemical bonds we have performed self-consistent calculations on a model with H2 standing upright on a jellium surface. Data for the adsorbate-induced electron structure and potential-energy curves with substrate parameters characteristic for Al, Mg and Na are presented. We extract concepts and trends that should be useful for other molecule-metal systems as well, e.g., (i) the downshift of the antibonding affinity level, in a symmetry-affected correlation with the effective electron potential of the clean surface, (ii) the filling of the corresponding molecular resonance, localized primarily on the outer H atom, (iii) the thereby weakened intramolecular bond, and (iv) the natural separation of the molecular chemisorption energy into intra- and extramolecular terms, whose relative size determines the molecular adsorption to be dissociative, activated etc. The model calculations provide illustrations of different classes of molecular chemisorption systems and support the Lennard-Jones description of molecular adsorption, provided that the molecular potential-energy curve is due to chemical rather than van der Waals' forces.
55 citations
TL;DR: In this article, a picture of hydrogen dissociation and recombination on surfaces is inferred on the basis of selfconsistent model calculations of the electronic structure of atomic hydrogen on and in jellium.
37 citations