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1	Topics in the Superconductivity of Simple Metals and Alloys Trofimenkoff, Peter Nicholas 11 1900 (has links) <p> The effects of hydrostatic pressure on the superconducting transition temperatures of the simple metals aluminum, lead, mercury, tin and indium are investigated within the strong-coupling theory of superconductivity. The experimental variation of the transition temperature with volume change can be understood within a simple scaling model. Strong-coupling effects in the pressure dependence of superconductivity in lead and mercury are investigated.</p> <p> A formalism which includes effects of force constant disorder on superconductivity in a binary alloy of simple metals is established within pseudopotential theory.</p> / Thesis / Doctor of Philosophy (PhD)
2	Free Molecular and Metal Clusters Studied by Synchrotron Radiation Based Electron Spectroscopy Rosso, Aldana January 2008 (has links) The main purpose of this Thesis is the experimental characterization of the electronic and geometric structures of objects called clusters. A cluster consists of a finite group of bound atoms or molecules. Due to its finite size, it may present completely different properties than those of the isolated atom and the bulk. The clusters studied in this work are constituted by rare-gas atoms, organic molecules, and metal atoms. Intense cluster beams were created using either an adiabatic expansion source or a gas-aggregation source, and investigated by means of synchrotron radiation based photoelectron spectroscopy. The reports presented in this Thesis may be divided into three parts. The first one deals with results concerning homogeneous molecular clusters (benzene- and methyl-related clusters) highlighting how molecular properties, such as dipole moment and polarizability, influence the cluster structure. The second part focuses on studies of solvation processes in clusters. In particular, the adsorption of polar molecules on rare-gas clusters is studied. It is shown that the doping method, i.e. the technique used to expose clusters to molecules, and the fraction of polar molecules are important factors in determining the location of the molecules in the clusters. Finally, a summary of investigations performed on metal clusters is presented. The applicability of solid state models to analyse the cluster spectra is considered, and the differences between the atomic, cluster and solid electronic structures are discussed. nanoparticles free clusters molecular clusters metal clusters photoelectron spectroscopy synchrotron radiation local structure core level spectroscopy auger spectroscopy heterogeneous clusters nucleation bromomethane chloromethane benzene bromobenzene chlorobenzene potassium sodium simple metals Physics Fysik
3	Modèle du pseudo-atome neutre pour l'étude de métaux simples dans le régime de la matière dense et chaude à deux températures Harbour, Louis 05 1900 (has links) No description available. Matière dense et chaude Métaux simples Potentiel de paires Warm dense matter Simple metals Pair-potentials Matière ultra-rapide Matière compressée par choc Équation d'état Phonon Phonon Quasi-équilibre Ultra-fast matter Shock compressed matter Equation of state Quasi-equilibrium

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