Sökning: "paramagnetic shifts"

Visar resultat 1 - 5 av 14 avhandlingar innehållade orden paramagnetic shifts.

1. 1. Paramagnetic relaxation reagents : nuclear magnetic resonance studies of preferential solvation

   Författare :Hans Grahn; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : The interactions between neutral paramagnetic relaxation reagents (PARR's) and certain aromatic compounds have been studied by 1H and 13 C spin-lattice relaxation time measurements. In media such as cyclohexane and carbon tetrachloride, Cr(acac)3 becomes preferentially solvated by aromatic solutes. LÄS MER

3. 2. New solid-state NMR methods for exciting and separating anisotropic interactions of spin I=1 nuclei

   Författare :Rihards Aleksis; Andrew Pell; Robert Schurko; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; solid-state NMR; quadrupolar; paramagnetic shifts; spinning solids; materials; Physical Chemistry; fysikalisk kemi;

   Sammanfattning : Solid-state NMR has become an essential tool for structural characterisation of materials, in particular systems with poor crystallinity and structural disorder. In recent years, a surge of interest has been observed for the study of paramagnetic systems, in which the interaction between nuclei and unpaired electrons allows to probe the electronic structure and properties of materials more directly. LÄS MER

4. 3. Theoretical Description of the Electron-Lattice Interaction in Molecular and Magnetic Crystals

   Författare :Elham Mozafari; Igor A. Abrikosov; Sven Stafström; George Malcolm Stocks; Linköpings universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Molecular crystals; Charge transport; Polaron; Magnetic materials; Paramagnetic state; Molecular dynamics;

   Sammanfattning : Electron-lattice interactions are often considered not to play a major role in material's properties as they are assumed to be small, the second-order effects. However, this study shows the importance of taking these effects into account in the simulations. LÄS MER

5. 4. Quantum chemical calculations of electron paramagnetic resonance of biological radicals

   Författare :Maria Engström; Shashi Karna; Linköpings universitet; []
   Nyckelord :;

   Sammanfattning : The aim of this thesis was to use state-of-the-art quantum chemical calculations of electron paramagnetic resonance (EPR) with applications to radicals in biomolecular systems. Special emphasis has been devoted to investigations of structure-to-property relations of amino acid radicals and spin labels in proteins. LÄS MER

7. 5. Density functional studies of EPR and NMR parameters of paramagnetic systems

   Författare :Lyudmyla G. Telyatnyk; Olav Vahtras; Martin Kaupp; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; spin-restricted DFT; restricted-unrestricted approach; EPR spin Hamiltonian parameters; NMR spin Hamiltonian parameters; Bioorganic chemistry; Bioorganisk kemi;

   Sammanfattning : Experimental methods based on the magnetic resonance phenomenon belong to the most widely used experimental techniques for investigations of molecular and electronic structure. The difficulty with such experiments, usually a proper interpretation of data obtained from high-resolution spectra, opens new challenges for pure theoretical methods. LÄS MER