Search for dissertations about: "A. Kohn"

Showing result 11 - 15 of 30 swedish dissertations containing the words A. Kohn.

  2. 11. Molecular Quadratic Response Properties with Inclusion of Relativity

    Author : Johan Henriksson; Patrick Norman; Juha Vaara; Linköpings universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; relativistic quantum chemistry; molecular physics; clamping levels; four-component Hartree-Fock theory; Kohn-Sham density functional theory; response theory; nonlinear optics; second-harmonic generation; two-photon absorption; excited state properties; optical power limiting; Computational physics; Beräkningsfysik;

    Abstract : This thesis concerns quadratic response properties and their application to properties in Jablonski diagrams such as resonant two-photon absorption and excited state absorption. Our main interest lies in optical power limiting applications, and in this context, molecules containing heavy metal atoms prove superior. READ MORE

  4. 12. Fock Matrix Construction for Large Systems

    Author : Elias Rudberg; Pawel Salek; Itai Panas; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; quantum chemistry; Theoretical chemistry; Teoretisk kemi;

    Abstract : This licentiate thesis deals with quantum chemistry methods for large systems. In particular, the thesis focuses on the efficient construction of the Coulomb and exchange matrices which are important parts of the Fock matrix in Hartree--Fock calculations. READ MORE

  5. 13. Magnetism and Structure in Metallic Multilayers

    Author : Erik Holmström; Turek Ilja; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Physics; Magnetism; Interfaces; Structure; KKR-ASA; CPA; Quantum Well; Fysik; Physics; Fysik;

    Abstract : The interplay between magnetism and structure has been studied in magnetic multilayers by electronic structure calculations based on density functional theory and analyzed in terms of models. The main ideas behind the Korringa-Kohn-Rostocker Green’s function method are described and the implementation of the coherent potential approximation is outlined. READ MORE

  6. 14. Quantum Chemistry for Large Systems

    Author : Elias Rudberg; Pawel Salek; Christian Ochsenfeld; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; quantum chemistry; fast multipole method; density matrix purification; sparse matrices; Theoretical chemistry; Teoretisk kemi;

    Abstract : This thesis deals with quantum chemistry methods for large systems. In particular, the thesis focuses on the efficient construction of the Coulomb and exchange matrices which are important parts of the Fock matrix in Hartree-Fock calculations. READ MORE

  7. 15. Matrix Algebra for Quantum Chemistry

    Author : Emanuel H. Rubensson; Pawel Salek; Stefan Goedecker; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; linear scaling; reduced complexity; electronic structure; density functional theory; Hartree-Fock; density matrix purification; congruence transformation; inverse factorization; eigenvalues; eigenvectors; numerical linear algebra; occupied subspace; canonical angles; invariant subspace; Theoretical chemistry; Teoretisk kemi;

    Abstract : This thesis concerns methods of reduced complexity for electronic structure calculations.  When quantum chemistry methods are applied to large systems, it is important to optimally use computer resources and only store data and perform operations that contribute to the overall accuracy. READ MORE