Sökning: "relativistic quantum chemistry"

Visar resultat 1 - 5 av 7 avhandlingar innehållade orden relativistic quantum chemistry.

  1. 1. Quantum and quantum-classical calculations of core-ionized molecules in varied environments

    Författare :Tuomas Löytynoja; Hans Ågren; Jukka Tulkki; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Electron spectroscopy; UPS; XPS; photodissociation; binding energy; ionization potential; computational; electronic structure; self-consistent field; DFT; QM MM; gas phase; liquid; solution; physisorption; metallic surface; polymer; charge transfer; Teoretisk kemi och biologi; Theoretical Chemistry and Biology;

    Sammanfattning : Computational quantum chemistry methods have been applied in two particular cases: to provide insight to photoionization induced fragmentation of HgBr2 and HgCl2 molecules, and to study core-electron binding energies and chemical shifts of molecules in liquid, surface adsorbed and polymeric environments in the framework of quantum mechanics/molecular mechanics (QM/MM). In the photodissociation studies the computational work is based on the relativistic Dirac equation as the systems present strong spin-orbit interaction affecting the fragmentation processes. LÄS MER

  2. 2. Extending relativistic linear response theory to address solvent effects

    Författare :Joel Creutzberg; Beräkningskemi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Response theory; Polarizable embedding; Complex Polarization Propagator; Relativistic effects;

    Sammanfattning : The central aim of this thesis is to derive, implement and test new methods to calculate various types of spectroscopies of compounds containing heavy elements in an aqueous environment. Methods that can target such systems have to consider the following:(i) It is crucial to take relativistic effects into account. LÄS MER

  3. 3. Traitement de l'interaction spin-orbite en chimie quantique et application à la réactivité des complexes d'actinides

    Författare :Emmanuel Fromager; Ulf Wahlgren; Christian Teichteil; Michael Dolg; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; quantum chemistry; actinides; charge transfer reactions; spin-orbit effects; Physics; Fysik;

    Sammanfattning : The recent methodological developments and the advent of faster computers enable nowadays to investigate theoretically the chemical reactivity of heavy element complexes. As an example we can mention actinide chemistry which is involved in the separation of nuclear wastes. LÄS MER

  4. 4. Density Functional Response Theory with Applications to Electron and Nuclear Magnetic Resonance

    Författare :Corneliu I. Oprea; Olav Vahtras; Antonio Rizzo; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; biochemistry; molecular physics; computer science; Theoretical chemistry; Teoretisk kemi;

    Sammanfattning : This thesis presents quantum chemical calculations, applications of the response function formalism recently implemented within the framework of density functional theory by our research group. The purpose of the calculations is to assess the performance of this perturbative approach to determining heavy atom effects on magnetic resonance parameters. LÄS MER

  5. 5. Theoretical calculations of heavy atom effects in magnetic resonance spectroscopy

    Författare :Corneliu I. Oprea; Hans Ågren; Patrik Norman; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; nuclear spin-spin coupling tensor; nuclear shielding tensor; heavy atom effect; hyperfine coupling tensor; restricted-unrestricted approach; Theoretical chemistry; Teoretisk kemi;

    Sammanfattning : This thesis presents quantum chemical calculations, applications of the response function formalism recently implemented within the framework of density functional theory (DFT) by our research group. The purpose of the calculations is to assess the performance of this perturbative approach to determining heavy atom effects on magnetic resonance parameters. LÄS MER