Search for dissertations about: "transition energies"

Showing result 1 - 5 of 155 swedish dissertations containing the words transition energies.

2. 1. Atomistic simulation and experimental studies of transition metal systems involving carbon and nitrogen

   Author : Jiaying Xie; Seshadri Seetharaman; Oleg Ostrovski; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Transition metal carbides; Transition metal nitrides; Transition metal carbo-nitrides; Lattice inversion method; Interatomic potential; Atomistic simulation; Metallurgical process engineering; Metallurgisk processteknik;

   Abstract : The present work was initiated to investigate the stability, structural and thermodynamic properties of transition metal carbides, nitrides and carbo-nitrides by atomistic simulations and experimentations. The interatomic pair potentials of Cr-Cr, Mn-Mn, Fe-Fe, C-C, Cr-C, Mn-C, Fe-C, Cr-Fe, Cr-N and Mn-N were inverted by the lattice inversion method and ab initio cohesive energies, and then employed to investigate the properties of Cr-, Mn- and Fe-carbides by atomistic simulations in this work. READ MORE

4. 2. Investigations of Transition Metal Systems : Angle-Resolved Photoelectron Spectroscopy at Low and High Energy

   Author : Thomas Claesson; Oscar Tjernberg; Kevin Smith; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; angle-resolved photoelectron spectroscopy; electronic structure; oxides; high-temperature superconductors; Material physics with surface physics; Materialfysik med ytfysik;

   Abstract : 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. READ MORE

5. 3. Magnetism in Transition Metal Systems : Interplay between structure, dimensionality and electron correlation

   Author : Samara Keshavarz Hedayati; Yaroslav Kvashnin; Patrik Thunström; Olle Eriksson; Tamio Oguchi; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

   Abstract : 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. READ MORE

6. 4. Microscopic Properties of Superdeformed Nuclei

   Author : Lennart B Karlsson; Matematisk fysik; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; statistical physics; gravitation; superdeformation; Nilsson-Strutinsky; modified oscillator potential; moments of inertia; transition energies; rotational bands; quadrupole moments; spin assignments; identical bands; additivity.; Mathematical and general theoretical physics; classical mechanics; relativity; quantum mechanics; kvantmekanik; klassisk mekanik; thermodynamics; Matematisk och allmän teoretisk fysik; termodynamik; relativitet; statistisk fysik; Fysicumarkivet A:1999:Karlsson;

   Abstract : Many high spin rotational bands in superdeformed nuclei have been found in the A ~ 140-150 region, but so far no linking transitions to known normal-deformed states have been found in these nuclei. Therefore, configuration and spin assignments have to be based on indirect spectroscopic information. READ MORE

7. 5. Modelling electrooxidation of glycerol and methanol on close-packed transition metal surfaces

   Author : Mikael Valter; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; implicit solvation; gold; Au 111 ; transition metals; biodiesel; electrochemistry; glycerol; DFT; van der Waals; methanol; scaling relations;

   Abstract : Burning fossil fuels leads to excess CO2 in the atmosphere, causing global warming, threatening civilisation and ecosystems worldwide. As a step in making the society fossil-independent, we need to replace oil, coal, and gas in the transportation sector with fuels originating from sustainable energy sources. READ MORE