Sökning: "Transition metal"
Visar resultat 16 - 20 av 629 avhandlingar innehållade orden Transition metal.
16. Investigations of Transition Metal Systems : Angle-Resolved Photoelectron Spectroscopy at Low and High Energy
Sammanfattning : The work presented in this thesis aims at achieving an increased understanding of the electronic structure of materials whose properties are to a large extent governed by transition metals. All studies are based on data from angle-resolved photoelectron spectroscopy (ARPES) employed on the valence band of the studied systems. LÄS MER
17. Magnetism in Transition Metal Systems : Interplay between structure, dimensionality and electron correlation
Sammanfattning : In this thesis, an ab initio study of electronic structures and magnetic properties of transition metal systems has been presented, covering bulk, interface and surface geometries. Among them are Fe, Co, Ni, CaMnO3, Co2MnSi, a ferromagnetic Heusler alloy, as well as double-perovskites oxides such as Sr3(Fe1.25Ni0.75)O6 and Nd2NiMnO6. LÄS MER
18. Transition Metal-Catalyzed Redox Reactions : A Journey from Homogeneous Ruthenium to Heterogeneous Palladium Catalysis
Sammanfattning : The first part of the thesis covers the development and utilization of electronically modified (pentaarylcyclopentadienyl)Ru-complexes in the racemization of secondary alcohols. This study revealed that the electronic properties of the substrate were the main factors dictating whether β-hydride elimination or hydride re-addition becomes the rate-determining step of the racemization process. LÄS MER
19. Catalytic Asymmetric Ketone and Alkene Reductions Using Transition Metal Complexes
Sammanfattning : This thesis contains seven papers dealing with iridium and ruthenium based catalytic asymmetric reductions, either of ketones into chiral alcohols, or olefins into chiral alkanes. The first part of the thesis describes how we have designed and evaluated new bicyclic ligands containing either N,S or N,N chelating atoms. LÄS MER
20. Microstructure aspects of transition metal carbide thin films
Sammanfattning : Transition metal carbides are important refractory materials used in many thin film applications. In this thesis, several transition metal carbides have been deposited using different chemical vapour deposition (CVD) and evaporation processes. In particular, the phase composition and microstructure of these carbide films have been studied. LÄS MER