Search for dissertations about: "Current density functional theory"

Showing result 1 - 5 of 63 swedish dissertations containing the words Current density functional theory.

2. 1. Foundation of Density Functionals in the Presence of Magnetic Field

   Author : Andre Laestadius; Michael Benedicks; Trygve Helgaker; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Current density functional theory; Hohenberg-Kohn theorems; paramagnetic current density functionals; Kohn-Sham theory; Levy-Lieb functional; variational principle; N-representable; degeneracy; Mathematics; Matematik;

   Abstract : This thesis contains four articles related to mathematical aspects of Density Functional Theory.In Paper A, the theoretical justification of density methods formulated with current densities is addressed. It is shown that the set of ground-states is determined by the ensemble-representable particle and paramagnetic current density. READ MORE

4. 2. Computational Insights on Functional Materials for Clean Energy Storage : Modeling, Structure and Thermodynamics

   Author : Tanveer Hussain; Rajeev Ahuja; Caetano R. Miranda; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Density functional theory; Molecular dynamics; Hydrogen storage; Chemisorption; Physisorption; Functionalization; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

   Abstract : The exponential increase in the demands of world’s energy and the devastating effects of current fossil fuels based sources has forced us to reduce our dependence on the current sources as well as finding cleaner, cheaper and renewable alternates. Being abundant, efficient and renewable, hydrogen can be opted as the best possible replacement of the diminishing and harmful fossil fuels. READ MORE

5. 3. First Principles Studies of Functional Materials Based on Graphene and Organometallics

   Author : Sumanta Bhandary; Biplab Sanyal; Olle Eriksson; Stefano Sanvito; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Graphene; Magnetism; Organometallics; Density functional theory; Electron correlation; Spin switching; Nanoribbons; Exchange interaction; Edge functionalization; Band gap; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

   Abstract : Graphene is foreseen to be the basis of future electronics owing to its ultra thin structure, extremely high charge carrier mobility,  high thermal conductivity etc., which are expected to overcome the size limitation and heat dissipation problem in silicon based transistors. READ MORE

6. 4. Spin Dynamics and Magnetic Multilayers

   Author : Björn Skubic; Olle Eriksson; Lars Nordström; Mark D. Stiles; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Physics; magnetism; electronic structure; density functional theory; spin dynamics; spin-transfer torque; spin-density wave; multilayer; interface structure; Fysik;

   Abstract : Theoretical studies based on first-principles theory are presented for a number of different magnetic systems. The first part of the thesis concerns spin dynamics and the second part concerns properties of magnetic multilayers. The theoretical treatment is based on electronic structure calculations performed by means of density functional theory. READ MORE

7. 5. Electronic structure studies and method development for complex materials

   Author : Andreas Östlin; Levente Vitos; László Udvardi; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; electronic structure theory; density functional theory; Teknisk materialvetenskap; Materials Science and Engineering;

   Abstract : Over the years electronic structure theory has proven to be a powerful method with which one can probe the behaviour of materials, making it possible to describe and predict material properties. The numerical tools needed for these methods are always in need of development, since the desire to calculate more complex materials pushes this field forward. READ MORE